WO2010057943A2

WO2010057943A2 - Analysis system for fuel analysis

Info

Publication number: WO2010057943A2
Application number: PCT/EP2009/065446
Authority: WO
Inventors: Klaus KÜHLING; Wolfgang Ahlers; Wolf Stegmaier; Michael Rapp; Nicole Barie
Original assignee: Basf Se
Priority date: 2008-11-20
Filing date: 2009-11-19
Publication date: 2010-05-27
Also published as: WO2010057943A3

Abstract

A method is proposed for identifying a material, in particular an organic liquid. The method comprises the following steps: - subjecting the material to at least one pyrolysis step, wherein at least one characteristic material results, - feed the characteristic material to at least one surface wave sensor (138; 212), wherein at least one sensor signal is generated, and – determining the identity of the material from the at least one sensor signal in an identification step.

Description

Analysis system for fuel analysis

description

Field of the invention

The invention relates to a method for identifying a material, in particular an organic liquid, as well as a device for identifying the material and a use of the method. Such methods, devices and combinations can be used in particular in the field of fuel analysis, for example in order to distinguish certain mineral oil products of a manufacturer of mineral oil products of foreign manufacturers. In particular, counterfeits can be detected in this way.

State of the art

In many fields of science, technology and medicine there is a need for a reliable and rapid analysis of materials in liquid, gaseous or solid form. The following description is particularly directed to analytics in the field of fuels or other mineral oil products, but is generally applicable to other types of materials, particularly organic liquids. In the field of fuel analysis, however, it is of particular importance to be able to analyze and thus identify fuels and other mineral oil products quickly and reliably, preferably on the spot, ie "on the spot." In this way, mineral oil products from one manufacturer of mineral oil products can be used Such forgeries can cause considerable economic damage and, in the case of inferior counterfeits, can even lead to damage, for example, to engines in which these mineral oil products are used.

From the multitude of possible analysis devices, which are generally suitable for an automated on-site analysis, surface wave sensors have proven to be particularly useful sensor systems in recent years. Surface wave sensors are acousto-electrical components in which acoustic waves are excited by means of a suitable electrode structure in a substrate material. In addition to pure surface waves, which can be excited, for example, by means of comb-like interdigitated electrode structures, other types of waves in solids can in principle also be used, and these types of sensors should also be included in the scope of the present invention by the term surface-wave sensors. Stores a material to be detected, for example, from a Gas phase or a liquid phase, on a sensor surface of the sensor, for example by adsorption and / or by chemical reaction or other type of attachment and / or bonding, so the acoustic properties of the solid state material of the surface acoustic wave sensor. This results in a shift of the frequencies of the excited waves, which is detectable as a corresponding sensor signal.

In order to enable a selective detection of certain materials by means of the surface acoustic wave sensors, at least one sensor surface of the surface wave sensors is usually pretreated in order to specifically favor the attachment of the materials to be detected. For example, suitable coatings, for example polymer coatings, can be used for this purpose, which for example selectively adsorb or otherwise bind certain substances or react with them. By using a plurality of surface acoustic wave sensors, for example in array form, for example, sensors with differently modified sensor surfaces and thus different selectivity with respect to the substances to be detected, can be performed in this way fast parallel evidence, or it can identify mixtures.

The technique of surface wave sensor analysis used in the present invention is described, for example, in JW Grate: "Acoustic Wave Microsensor Arrays for Vapor Sensing", Chem. Rev. 2000, 100, 2627- 2648. Further embodiments are possible and also usable in the context of the present invention surface acoustic wave filters are described in US 6,640,613 B2, DE 102 22 068 A1 and DE 197 46 261 A1.

However, surface wave sensors of the type described are not readily usable for the analysis of organic liquids, in particular of fuels and / or other mineral oil products. In the first place, it was possible to obtain easily analyzable gases of sufficient concentration from the organic liquids in most cases due to the vapor pressure. However, the question arises as to whether the gas composition reflects or correlates with the actual composition of the organic liquid. Furthermore, in many cases, modification or coating of the sensor surfaces constitutes a weak point of surface acoustic wave sensors. Mineral oil products and other organic liquids in many cases contain aggressive components, in particular components with solvent properties, which can influence or destroy these surface modifications. For example, mineral oil products can dissolve or at least attack polymer coatings on the sensor surfaces, so that a reproducible measurement is no longer guaranteed. Furthermore, irreversible changes in the sensor surfaces or on the sensor surface can result from condensation. chen, which can lead to false signals for subsequent measurements.

Object of the invention

It is therefore an object of the present invention to provide a method and a device which are also suitable for the identification of aggressive materials such as in particular organic liquids and still allow a fast and reliable analysis.

Description of the invention

This object is achieved by the invention with the features of the independent claims. Advantageous developments, which can be implemented individually or in combination, are presented in the dependent claims. In this case, a method and a device are proposed, wherein the method can be carried out using in particular the device, and wherein the device can be set up to carry out the method according to the invention. Accordingly, for possible embodiments of the device, reference may be made to the description of the method, with corresponding method features being able to be re-used, for example, by corresponding devices for carrying out the individual method steps. Accordingly, for possible details of the method, reference may be made to the description of the possible embodiments of the device.

A basic idea of the present invention is that not all constituents of the material are required for an identification of the material, but that many materials either themselves already contain as one constituent characteristic materials, by means of which alone the identification of the material is possible or that such characteristic materials can be generated selectively.

These characteristic materials may be, for example, separable components, fragments, reaction products or similar materials that can be produced from the material to be identified. If these characteristic materials are produced in such a way that they are substantially harmless to the aforementioned coatings or surface modifications of conventional surface acoustic wave sensors, the problem described above can be solved in a simple manner. Thus surface wave sensors can be used in order to identify the actual material via the at least one characteristic material that in this case a damage or change of the surface acoustic wave sensors, in particular sensor surfaces of these surface acoustic wave sensors occurs.

The proposed method for identifying a material, in particular an organic liquid, that is to say a liquid which comprises at least one organic material, comprises the following method steps, which are preferably carried out in the stated order. However, another order of the method steps is possible in principle. Additional, unlisted method steps may also be included, and one or more method steps may also be performed simultaneously or temporally overlapping or repeatedly.

In a first process step, the material is subjected to at least one pyrolysis step. A pyrolysis step is to be understood as meaning a thermal treatment of the material with at least one elevated temperature, which is suitable for bringing about chemical changes in the material. In particular, this may be a thermal cracking of the material into smaller components. For example, the pyrolysis step, depending on the material used or used to be identified material class, temperature treatments at pyrolysis Temperatures above 500 ⁰ C include. Pyrolysis with more than one pyrolysis temperature is also conceivable, for example a pyrolysis with a ramp-shaped or stepped course with a sequence of several different pyrolysis temperatures. The pyrolysis step is carried out in such a way that at least one characteristic material is produced from the material to be identified. A combination of several characteristic materials can also arise. By a characteristic material is meant a detectable by a surface wave sensor product of the pyrolysis step, which is characteristic of the material to be identified, that is that from a detection of the characteristic material or a combination of the characteristic materials with high probability on the presence of a particular Material or a material class can be closed.

In a second method step, the at least one characteristic material is supplied to at least one surface wave sensor. In principle, all types of surface-wave sensors described at the beginning can be used, so that with regard to possible embodiments of the at least one surface-wave sensor, reference may be made to the above description and the cited literature. In addition to pure surface waves, which can be excited, for example, by means of comb-like interdigitated electrode structures, in principle other types of waves can also be used in solids, whereby these types of sensors are also referred to in the context of the present invention by the term surface wave radiation. should be recorded. In general, the term "surface wave sensor" should therefore be understood broadly in the context of the present invention and include any type of gravimetric sensors, in particular the mentioned types of surface wave sensors and in particular at least partially target substance-selective sensors, for example coated, in particular polymer-coated, gravimetric - trical sensors. Other examples that could be mentioned are quartz crystals and acousto-electric microresonators, especially so-called FBARs (Thin Film Buick Acoustic Wave Resonators). Combinations of the mentioned and / or other types of sensors are conceivable. In particular, multiple frequency ranges can thereby be covered, for example frequency ranges from 5 MHz to 100 MHz by means of quartz crystals and / or, for example, from 1 GHz to 10 GHz by FBARs. By suitable combinations or by suitable selection of surface wave sensors according to this definition, optimal configurations can be accomplished for given tasks, for example with regard to predetermined boundary conditions and / or objectives, in particular sample volumes, sample gas flows, desired detection sensitivity, reaction time, technical implementation or like.

At least one sensor signal is generated by the surface wave sensor, that is to say an evaluable signal which can basically be in any desired form, that is, for example in the form of a signal amplitude, a frequency, a frequency shift, a phase, in electrical or electromagnetic form or in another signal form.

In a third method step, the identification step, the identity of the material is finally deduced from the at least one sensor signal. Corresponding methods are known in principle to the person skilled in the art. Closing to the identity of the material can be done, for example, by using at least one data processing device, although, for example, a manual evaluation is also possible. A data processing device may for this purpose include, for example, a processor, one or more volatile and / or nonvolatile memories, interfaces, input and / or output means or similar components typically included in data processing equipment, and in particular may be program-programmed to perform the identification step. For example, the identification step can take place in that the at least one sensor signal is analyzed analytically, empirically or semiempirically. For example, the at least one sensor signal can be compared with known sensor signals of known characteristic materials and / or known materials. This comparison can be done, for example, by means of a correlation method. In this way materials can be directly identified and / or the materials can be identified by means of characteristic materials. Accordingly, the device, which may be equipped in particular for carrying out the proposed method, comprise at least one pyrolysis device for at least partial pyrolysis of the material. In particular, this pyrolysis device may comprise one or more ovens and / or other types of heaters. Embodiments of such pyrolysis devices will be explained in more detail below.

Furthermore, the device comprises at least one surface wave sensor and is arranged to supply the at least one characteristic material generated in the pyrolysis device to the surface wave sensor. This surface wave sensor should be set up to generate at least one sensor signal. For example, as stated above, this surface wave sensor can have at least one sensor surface which, for example, can be selectively modified in order to detect the at least one characteristic material. For example, this sensor surface can be purposefully coated for this purpose, for example by means of appropriate organic coatings and / or polymer coatings or other types of surface modifications, for example surface films or the like. In contrast to known methods and devices in which no pyrolysis step takes place, however, the pyrolysis step can be arranged on the surface wave sensor such that the at least one characteristic material does not or only insignificantly damages this sensor surface, as for example in the direct supply of organic liquids and / or gases is often the case.

The at least one sensor signal which is generated in the proposed device can then be evaluated manually, as explained above. However, it is particularly preferred if the device further comprises at least one identification device, in particular an identification device for carrying out the above-described identification step, which is arranged to close from the at least one sensor signal to the identity of the material.

In general, the term closing refers to the identity of the material in the context of the present invention. Thus, on the one hand, this identification can make a clear statement about the type of material, for example the specification of a specific substance or substance mixture as material. However, it is also possible and covered by the concept of identification, for example, a classification, that is, a statement about which substance class the material is to be assigned, or which substance class or which substance classes the material is not assigned. Even more general statements are possible in the context of the identification step and are included by definition, for example statements about a source of the material, such as Make a statement as to whether it is an original product or an unauthorized substance. For example, the identification step may include a statement as to whether the material is a mineral oil product of a particular manufacturer or not. Other types of statements about the material should also be included in the concept of the identity of the material and can be determined in the context of the identification step.

In a preferred embodiment of the method, the material is subjected before the at least one pyrolysis step at least one further thermal treatment step, in particular a thermal treatment step in which no pyrolysis in the sense of the above definition occurs. In particular, this at least one further thermal treatment step may comprise at least one evaporation step in which volatile constituents of the material are at least partially removed from the material. This development of the invention has the advantage that components of the material which could damage the surface wave sensor or a sensor surface of the same, for example, can be specifically removed from the material before the pyrolysis step is carried out. In this way, for example, volatile and aggressive components of mineral oil products can be specifically removed before the actual pyrolysis is carried out, so that these components preferably can not get to the surface wave sensor.

For example, the thermal treatment step may include at least one evaporation step. In particular, pyrolysis of major components in a fuel, such as octane and / or decane, may in many cases prove difficult or impossible at preferred pyrolysis temperatures. In addition, a direct pyrolysis of the entire fuel including the main components octane and / or decane due to the required heat of evaporation can be technically difficult and also lead to a risk of explosion. The preferred at least one evaporation step, which is preferably connected upstream of the pyrolysis, can avoid or at least reduce this problem.

The at least one thermal treatment step, in particular the at least one evaporation step, can also be used for enrichment, for example for enriching low-volatility constituents of the organic liquid, for example by evaporating a higher amount of fuel. Optionally, the thermal treatment step can also be carried out several times in order to achieve even higher enrichment factors, in particular in an apparatus-defined volume.

The at least one further thermal treatment step can be carried out at temperatures which depend on the material to be identified, on which already existing information is already being carried out. In particular, in organic liquids, such as mineral oil products, but also in other types of materials, temperatures between 50 ⁰ C and 200 ⁰ C have been found to be suitable to at least partially remove aggressive volatiles, which could damage the at least one surface wave sensor. Particularly preferred are temperatures between 100 ° C and 150 ⁰ C.

Alternatively or in addition to avoiding damage by aggressive components, saturation effects can also be effectively avoided by the thermal treatment step. In particular, major fuel components, which are less aggressive in many cases, are present in large quantities in the organic sample. The large amount alone could therefore lead to saturation effects in the case of surface wave sensors during evaporation and thus to poor repeatability of the measurements. As a result of the thermal treatment step, in particular the at least one evaporation step, it is therefore also possible to remove non-interest and volatile constituents of the liquid sample, for example main constituents of a fuel, which would unnecessarily overload the sensors. A risk of explosion due to components of the liquid sample, which can lead to explosive mixtures, for example, in contact with air, can be avoided by at least partial removal of these components before pyrolysis.

The duration of the at least one further thermal treatment step can also be adapted to the type of material and / or the class of material to be examined. For practical reasons, time durations between 1 minute and 2 hours have proven to be particularly suitable here, in particular periods of about 1 hour. Several further thermal treatment steps are also possible, for example combinations of further thermal treatment steps at different temperatures, for example in the context of a stepped temperature profile, a ramped temperature profile or similar thermal treatment steps.

To carry out the at least one further thermal treatment step, the proposed device may in particular comprise at least one thermal device. By way of example, this thermal device may be a simple oven in which the material, for example received in one or more crucibles, is pretreated. For example, the thermal device may include one or more heating blocks into which one or more crucibles may be received to be heated evenly. Other types of thermal devices are also possible, for example, devices in which the material is heated by infrared treatment, by microwaves, by other types of electromagnetic radiation, or otherwise. Various such Thermal devices are known in the art. The thermal device may be integrated directly into the remaining components of the device, but may also be designed as a separate component of this device, as will be explained in more detail below.

In particular, the thermal device may be configured such that in the thermal treatment step, in particular evaporation, released constituents of the liquid sample do not come into contact or at least only partially with the surface wave sensor. Accordingly, the thermal device may be configured to be separated from the surface acoustic wave sensor. An arrangement in a bypass is possible, for example in a switched bypass, which prevents such contact at least substantially. In this way, the sensor of the surface acoustic wave sensor can be spared, for example, by this is shielded by not interesting for the measurement of the main fuel components.

Further advantageous embodiments of the invention relate to the supply of the characteristic material to the surface wave sensor. This supply can be effected in particular by means of at least one carrier gas. For example, ambient air, synthetic air, nitrogen, argon or other types of carrier gases or carrier gas mixtures can be used for this purpose as carrier gases. For example, a gas delivery of the carrier gas by a gas pump in the pressure mode or, which is preferred, take place in the suction mode. If appropriate, the carrier gas can be dried before use and / or targeted adjustment of moisture in the carrier gas can take place. For supplying the characteristic material by means of the at least one carrier gas, in particular at least one piping system may be provided, for example a piping system which connects the pyrolysis device to the at least one surface wave sensor. The at least one piping system may include, for example, glass tubes, quartz tubes, plastic pipes or similar pipes or pipe combinations, wherein the term "pipe" mutatis mutandis hoses or other types of pipe devices are to be understood, which is the supply of the carrier gas, that is, a targeted conduction of the carrier gas The piping system can be additionally purged with the carrier gas, for example before the at least one pyrolysis step is carried out, in order to allow a purging of the piping system and / or of the material which has not yet pyrolyzed.

Further advantageous embodiments of the invention relate to the implementation of the

Pyrolysis step. In particular, this pyrolysis step can in turn be adapted to the nature of the material and / or the class of material, and / or to the nature of the at least one characteristic material to be produced. For example, the properties of the at least one characteristic material can be influenced via the parameters of the pyrolysis step, for example a size of the fragments produced during pyrolysis. The at least one identification step can be carried out, for example, taking into account these pyrolysis parameters, for example by using specific identification parameters for a specific parameter set of the pyrolysis. For example, a database can be used which contains specific comparison patterns or pattern signals for a specific set of pyrolysis parameters. Alternatively or additionally, however, the pyrolysis can always be carried out at the same pyrolysis parameters.

It has proven to be particularly preferable if the pyrolysis step is carried out at temperatures of at least 500 ^° C. Particularly preferred are regions of between 550 ⁰ C and 900 ° C, in particular between 600 ⁰ C and 650 ° C. Many of the materials to be identified, in particular organic liquids, such as, for example, mineral oil products, can be pyrolyzed in this way into certain characteristic materials. At the same time, such temperatures are still technically feasible and easily integrated, for example, in a piping system of the type described above by means of a suitable pyrolysis.

As a rule, at least one pyrolysis step produces a plurality of products which can all be used as characteristic materials, but which can also be subjected to one or more separation steps in order to supply only one or more of these products as characteristic materials to the surface wave sensor. In the latter case, different separation devices can be used. For example, a cold trap may be used as the separator, and / or the characteristic material or mixture of the characteristic materials may be subjected to at least one cooling step in order to condense low-volatility constituents. This cooling step can in principle be carried out at temperatures below the pyrolysis temperature, preferably at temperatures below 50 ° C. Particularly preferred are temperatures of at most 25 ° C, so that, for example, a simple cooling by ambient air, is sufficient. For example, the supply of the characteristic materials may comprise a condensing section in which these low-volatility materials can condense without being supplied to the surface wave sensor, for example a bend or a loop of a pipeline system.

Further preferred embodiments relate to the identification step. For example, this identification step can be carried out in such a way that it deliberately searches for at least one marker material of the material. This marker material may for example be admixed with the material, the characteristic material being, for example, a characteristic material consisting of the marker material is formed. Thus, for example, the material can be added specifically marker materials which form particularly reliable or reliable detectable characteristic materials in the pyrolysis step.

As a marker material special marker materials can be used. Another possibility, which is alternatively or additionally feasible, however, is to use marker materials already contained in the starting material, preferably low-volatility marker materials, and / or to define components already present in the starting material as marker materials. Thus, for example, various mineral oil products are already admixed with additives or additive mixtures which could also serve as marker materials whose fragments could be specifically detected as characteristic materials after pyrolysis. Such additives, which are frequently also referred to as "performance packages", are commercially available, for example, under the trade names Keropur® for gasoline or Kerupur® DP for diesel fuels from BASF SE, Germany Such packagings may include, for example, carrier liquids, solvents, conductivity improvers, marking agents and / or dyes, friction modifiers, detergents, corrosion inhibitors, defoamers, dehazers, lubricity improvers, cetane improvers or similar materials or mixtures of materials One advantage of using these performance packages is that they are mixed with the mineral oil products anyway and that these are characteristic of a particular manufacturer, so that an additional expense for the addition of an additional marker material can be omitted.

As described above, in the at least one identification step, for example, a database of sensor signals can be used, for example sensor signals associated with a plurality of deposited characteristic materials. For example, one or more correlation methods can be used in the identification step, for example to compare the sensor signals of a plurality of characteristic materials stored in the database with the respective sensor signals of the surface sensors and to determine matches. In this way, for example, probabilities can be specified that certain materials are present and / or a fully automatic identification can take place.

Further advantageous embodiments relate to details of the device according to the invention. Thus, in particular, the pyrolysis device may comprise at least one quartz tube in order to carry out the pyrolysis in this quartz tube. The device may, for example, comprise at least one crucible for receiving the material, for example a metal or ceramic crucible, in particular a stainless steel crucible. Of the- Such crucibles can accommodate, for example, samples in the microliter range, down to the terbereich, the material, such as the organic liquid. These crucibles can be transferred, for example, into the device. Alternatively or in addition to the use of crucibles, however, the direct introduction of the material into the device is basically possible, but in many cases less preferred in order to avoid soiling of the device.

As described above, the apparatus preferably further comprises at least one piping system. It is particularly preferred if the pipeline system can be connected to a carrier gas source in order to supply the characteristic material through the pipeline system to the surface wave sensor. This connection to the carrier gas source can take place, for example, via one or more corresponding nozzles, tubes or other types of interfaces. The carrier gas source may comprise, for example, a carrier gas source fixedly installed on the building side, but may alternatively or additionally also comprise a mobile carrier gas source, for example one or more gas cylinders. Alternatively or additionally, the carrier gas source may also comprise, for example, an air pump, for example for conveying outside air as a carrier gas, for example in suction operation. Furthermore, the carrier gas source may also comprise a drying unit and / or a conditioning unit, for example for adjusting a moisture content of the carrier gas. The carrier gas source itself may also be part of the device. The connection of the piping system to the carrier gas source may further include one or more valves or other devices for controlling the flow of the carrier gas.

A further preferred embodiment of the invention relates to at least one triggering device. Thus, it has been shown that the evaluation of the at least one sensor signal is particularly favorable and is simplified if the method is started at a precisely defined point in time. Accordingly, it is proposed to provide a triggering device which is set up to supply the material to the pyrolysis device at a defined time. In this way, the pyrolysis begins at a defined starting time, so that a high reproducibility is ensured with respect to the occurrence of the sensor signals.

The at least one triggering device can in principle be designed in any manner which starts the pyrolysis at a defined time. However, it is particularly preferred and technically easy to implement if the triggering device comprises at least one holding device which can hold the material, directly or held by a crucible. The device should then be set up in such a way that, when the holding device is released, the material falls into a pyrolysis position of the pyrolysis device. The use of gravitational forces allows one fast and reproducible start of the pyrolysis process. In principle, however, another type of transfer device can be integrated into the triggering device, which transfers the material quickly and reliably into the pyrolysis position.

Alternatively, it is also possible to dispense with a transfer device. In this case, for example, the material may be positioned in the pyrolysis position from the beginning. The process can then be carried out simply by starting the heating of the pyrolysis process at a fixed position. The heater itself may then function as one embodiment of a trip device.

Irrespective of the use of a triggering device and / or a transport device, the method and the device can generally be set up in such a way that a defined amount of the material is subjected to pyrolysis at a defined starting time. For example, a specific technical triggering of the pyrolysis by a rapid transfer of a specimen in a corresponding heated pyrolysis zone and / or by defined, rapid heating of a defined amount of a test specimen located in one place, for example by means of a microwave irradiation and / or one laser bombardment.

A further preferred embodiment relates to the surface wave sensor itself. As stated above, it may in principle comprise any of the surface wave sensors described above. However, it is particularly preferred if the surface wave sensor comprises a plurality of surface acoustic wave sensors, each of which is arranged to detect different characteristic materials. For this purpose, the individual surface acoustic wave sensors can, for example, have differently functionalized and / or coated sensor surfaces which have different sensitivities with respect to different characteristic materials. For example, the plurality of surface acoustic wave sensors may be configured as an array of surface acoustic wave sensors, for example on a single chip or a single board. For possible embodiments of this further development of the invention, reference may be made, for example, to DE 197 46 261 A1 and the exemplary embodiments described therein.

Further embodiments of the invention take advantage of the fact that the method described and the device described can be easily integrated into compact devices. Thus, it is particularly preferred if the device is designed as a mobile device, in particular as a portable handheld device. Under a portable handset while a device to be understood, which is transportable by a person without the aid of additional transport. Alternatively, the mobile device may also comprise other types of devices which are generally mobile. tet are. For example, such mobile devices can be accommodated or receivable in a suitcase, which if necessary can also be provided with transport devices such as rollers or the like. A mobile transport in a motor vehicle, in particular a passenger car, can be done. In this way, for example, a mobile device for mobile identification of the material can be provided.

It is particularly preferred, as stated above, if the method and / or the device for distinguishing between authorized and unauthorized products are used. In particular, in this way mineral oil products, fuels or alcohols can be identified and identify plagiarism or unauthorized materials. This in turn is particularly preferred in connection with the portable handset described, which can be used, for example, at gas stations or similar facilities to operate for example in the context of mobile controls counterfeiting.

Alternatively or additionally, the method described can also be used in one or more of the embodiments described above for quality assurance of the material. This is likewise possible, for example, for mineral oil products, but also for other types of materials. Thus, for example, an additive concentration, for example one or more of the additives described above, can be checked for their correctness. For example, this control can be done immediately during the mixing of the additive, or at a later time. In the latter case, for example, once again a mobile handheld device can be used.

embodiments

Further details and features of the invention will become apparent from the following description of preferred embodiments in conjunction with the subclaims. In this case, the respective features can be implemented on their own or in combination with one another. The invention is not limited to the embodiments. The exemplary embodiments are shown schematically in the figures. The same reference numerals in the individual figures designate the same or functionally identical or with respect to their functions corresponding elements. In detail shows:

Figure 1 shows a schematic structure of a device according to the invention;

FIG. 2 shows a surface wave sensor array for use in a device according to the invention;

FIG. 3 shows an exemplary embodiment of the measurement signals of the surface wave sensors of the surface wave sensor array according to FIG. 2 in an example measurement;

FIG. 4 calibration lines at different concentrations of a marker material; and

FIG. 5 shows a spider-web diagram of the measurement results according to FIG. 4.

1 shows a highly schematic form of an embodiment of a device 1 10 according to the invention for the identification of a material, by means of which an embodiment of the method according to the invention is to be explained. The device 10 initially comprises a thermal device 12 in the form of a heating device. This heating device, which may comprise, for example, a heatable perforated plate 14, can be used, for example, to heat a multiplicity of crucibles 116, for example stainless steel crucibles, to temperatures between 50 and 200 ^° C., in particular between 100 ^° C. and 150 ^° C. To carry out the method, first the crucibles 16 are filled with the material to be identified, preferably with a precisely defined or exactly known amount of the material to be detected. Subsequently, these crucibles 16 with the material contained in the thermal device 112 are subjected to the above-described thermal treatment step.

The apparatus 110 further comprises a piping system 18. This piping system 18 includes at one end a crosspiece 120, which may be made of quartz or metal, for example. For example, a commercially available cross piece from Swagelok in Karlsruhe, Germany, can be used as the crosspiece 120. The crosspiece 120 comprises an insertion opening 122 which can be closed by a plug 124 or, alternatively or additionally, by a screw connection for insertion of the crucibles 16. Furthermore, the crosspiece 120 comprises a release opening 126, which can be closed by a perforated plug 128. Alternatively, or in addition to a perforated plug, for example, can be closed by a union nut with a pierced septum. Furthermore, the crosspiece 120 comprises a carrier gas opening 130, which via a suitable carrier gas supply 132, for example one or more tubes, with a carrier gas source 134, for example, a source of synthetic air and / or nitrogen, is connectable.

Furthermore, the device 1 10 comprises a pyrolysis device 136, for example in the form of a ring furnace and / or tube furnace, which annularly surrounds a quartz tube section of the pipeline system 118. The pyrolysis device 136 may, for example, also comprise additional devices, for example control devices, energy sources or the like.

Furthermore, the device 110 comprises a surface wave sensor 138, which is explained in more detail below by way of example with reference to FIG. This surface wave sensor 138 has an inlet port 140 which is connected to the piping 118. Between the inlet stub 140 and the pyrolysis device 136, a cold trap 142 is provided, in which the piping system 118 comprises a collection sheet 144, in which low volatiles can condense out and collect. The cold trap 142 may include active cooling, but may also include simple cooling of the collection sheet 144 by air.

Furthermore, the surface wave sensor 138 includes an outlet port 146 through which the carrier gas can flow out of the surface wave sensor 138. The surface wave sensor 138 further includes an interface 148 via which the surface wave sensor 138 may be connected to a computer system 152, for example, via a data link 150. The computer system 152 can act, for example, as an identification device 154 or as part of such an identification device and can perform the identification step described above in whole or in part. Furthermore, the computer system 152 can also control further components of the device 110, for example the pyrolysis device 136, the carrier gas flow, the thermal device 12 or a triggering device 156, which is described in greater detail below.

As described above, the trigger opening 126 of the crosspiece 120 is closed in the illustrated embodiment by means of the pierced plug 128 and / or by means of the union nut with the pierced septum. By means of this pierced plug 128, as part of the triggering device 156, a wire 158 is guided, by way of which a crucible 16 can be held in a holding position 160 in the center of the crosspiece 120.

After carrying out the thermal treatment in the thermal device 112 is a crucible 1 16 with the material contained in the piping system 1 18th transferred. This is indicated symbolically in FIG. 1 by the reference numeral 162. For this purpose, the plug 124 is removed at short notice, and the crucible 1 16 is brought by the insertion opening 122 in the holding position 160. Subsequently, the insertion opening 122 is closed again by the plug 124. In the holding position 160, a rinsing step can then be carried out, for example in order to at least substantially clean the pipeline system 18 at least substantially by means of rinsing with carrier gas of air or other undesirable volatile or gaseous constituents, such as moisture.

Thereafter, triggering device 156 may then be actuated, for example, under the control of computer system 152. For this purpose, wire 158 may, for example, be withdrawn from crosspiece 120 so that crucible 116 is released and falls from holding position 160 to a pyrolysis position 164. In this pyrolysis position 164, the crucible 16 is held in the pipeline system 118 by a constriction 166. It should be noted that, instead of a transfer by gravity from the holding position 160 to the pyrolysis position 164, another type of transfer can be used.

In this pyrolysis position 164 then the pyrolysis takes place. In this case, as described above, the at least one characteristic material is formed. From this at least one characteristic material, in turn, as described above, low volatility constituents in the cold trap 142 can be condensed out. Other characteristic materials are introduced into the surface wave sensor 138 through the flow of the carrier gas via the inlet port 140.

FIG. 2 shows an exemplary embodiment of a surface wave sensor 138. This surface wave sensor essentially corresponds in terms of its construction to the sensor structure described in DE 197 46 261 A1, so that reference can be made to this document with regard to possible details and details.

The surface wave sensor 138 is configured in the illustrated embodiment according to Figure 2 as a surface wave sensor array 210 and includes a plurality, in this embodiment eight, single surface wave sensors 212, which are each shown only schematically in the illustrated embodiment. Each of these individual surface acoustic wave sensors 212 each includes a sensor surface 214. For example, these sensor surfaces 214 may be differently coated to have different sensitivities for different characteristic materials. The carrier gas with the characteristic materials contained therein can be guided, for example, through one or more grooves in a sensor chip of the surface wave sensor array 210 via these sensor surfaces 214. Furthermore, the surface wave sensor 138 according to FIG. 2 comprises an encapsulated reference oscillator 216. This reference oscillator 216 is not exposed to the carrier gas and / or the characteristic materials contained therein. Via a frequency mixer 218, the signals of the reference oscillator 216 can be mixed with those of the individual surface acoustic wave sensors 212 in order to be able to determine, for example, frequency shift. Furthermore, in the exemplary embodiment according to FIG. 2, the surface wave sensor 138 comprises a field-programmable gate array (FPGA 220) and / or other control components, which evaluate the signals of the individual surface wave sensors 212 and / or a total signal of the surface wave sensor 138 or a Prepare these signals. The actual evaluation can also take place in the computer system 152, in whole or in part.

FIG. 3 plots, as an example, sensor signals of the individual surface wave sensors 212, for example of the surface wave sensor array 210 according to FIG. 2, as a function of time. In each case difference curves are shown, wherein at the beginning of each measurement all difference frequencies have been set to zero. The measured curves 310 to 324 designate the sensor signals of the individual surface wave sensors 212, plotted as frequency f in Hertz as a function of time t in seconds. The reference numerals 326 and 328 designate the lower or upper limit of the measuring window, within which an evaluation of the frequency profiles 310 to 324 takes place.

In the region of the lower limit 326 of the measuring window, the measurement is started, for example by actuating the triggering device 156 as described above. At a time shifted from this triggering event by approximately 35 seconds, which is determined by the pyrolysis conditions and / or the flow of the carrier gas, the individual surface acoustic wave sensors 212 register a corresponding change and the frequencies of these surface acoustic wave sensors 212 begin to shift. In the different course of the individual frequency profiles 310 to 324 of the differently coated or differently sensitive individual surface wave sensors 212, the different sensitivity is expressed. While frequency curve 312 shows the strongest change, frequency curve 320 shows the lowest interaction with the characteristic material to be detected.

For the experiment shown in FIG. 4, a surface wave sensor

Array 210 is used as described in FIG. The material used was octane containing 500 ppm of the fuel additive Kerocom® described above

PIBA (polyisobuteneamine) were added. The thermal pretreatment (in- Steaming) was carried out on a hot plate at about 150 ⁰ C for about 15 minutes and then pyrolysis at about 630 ⁰ C.

The different sensitivity of the individual surface sensors 212 can clearly be seen in FIG. 3, so that a composition could already be deduced from this "fingerprint" of the individual sensor signals in order to show that the individual sensor signals also correspond to the quantity of the characteristic material to be detected Concentration curves with different admixtures of the above-mentioned additive Kerocom® PIBA were recorded, which are plotted in Figure 4. In each case the frequency shift Δf in Hz is plotted for different volume concentrations c, indicated in ppm, showing in each case the maximum frequency shift Δf 4, for example, the maximum of the frequency profiles 310 to 324 in Figure 3. The concentrations were varied from 0 ppm to 1000 ppm for the measurements according to Figure 4. The frequency shifts Δf of the individual surface acoustic wave sensors recorded thereby 212 are, according to the curves 310 to 324, designated in Figure 4 by the reference numerals 410 to 424.

Again, the calibration lines 410 to 424 show the different sensitivity of the individual surface wave sensors 212 from the course. If these calibration lines 410 to 424 are known, it is possible, for example with the aid of the identification device 154, to deduce, for example, a concentration of the marker from a specific maximum frequency shift.

In Figure 5, this relationship between the concentration and the different sensor signals is again in a spider chart (also called radar plot) plotted. Starting from the zero point located in the middle, the sensor signals of the individual surface wave sensors 212, designated by the numbers 1 to 8 in FIG. 5, are respectively applied in the direction of the corners of a spider web.

Curve 510 indicates the signal of an unfilled crucible 116, which was used as a blank. The signal 512, however, denotes the signal of a filled with pure octane crucible 1 16, so a blank sample without marker substance. Signals 514 through 522 indicate the signals for samples of 10 μl of octane at 100 ppm, 200 ppm, 300 ppm, 500 ppm, and 1000 ppm, respectively, in terms of volume concentration of Kerocom® PIBA as the marker.

It can be seen on the basis of these spider-web diagrams in FIG. 5 that already 100 ppm of the marker substance, corresponding to 1 nl of substance in the sample, by means of the proposed method differs significantly from the blank 510 or from the blank. sample 512 and can be detected in this way. Such spider-web diagrams can also be evaluated automatically, for example by means of appropriate correlation methods, so that an evaluation can be carried out quickly and reliably and with high reproducibility by means of the proposed method.

LIST OF REFERENCE NUMBERS

110 Device for identifying a material 112 thermal device

114 perforated plate

116 crucible

118 pipeline system

120 cross piece 122 import opening

124 plugs

126 trigger opening

128 drilled plugs

130 carrier gas opening 132 carrier gas supply

134 carrier gas source

136 pyrolysis device

138 surface wave sensor

140 inlet nozzle 142 cold trap

144 collection sheets

146 outlet

148 interface

150 data connection 152 computer system

154 identification device

156 triggering device

158 wire

160 Hold position 162 Transfer

164 pyrolysis position

166 constriction

210 surface wave sensor array 212 single surface wave sensors

214 sensor surface

216 reference oscillator

218 frequency mixer

220 FPGA 310-324 frequency curves of the individual surface acoustic wave sensors 212

326 lower limit measurement window

328 upper limit measurement window

410-424 calibration lines of the individual surface acoustic wave sensors 212

510 Blank sample empty crucible

512 zero sample octane

514 octane with 100 ppm Kerocom® PIBA 516 octane with 200 ppm Kerocom® PIBA

518 octane with 300 ppm Kerocom® PIBA

520 octane with 500 ppm Kerocom® PIBA

522 octane with 1000 ppm Kerocom® PIBA

Claims

1Patentansprüche

1. A method for identifying a material, in particular an organic liquid, comprising the following steps: - the material is subjected to at least one pyrolysis step, wherein at least one characteristic material is formed, the characteristic material is fed to at least one surface acoustic wave sensor (138; 212), wherein at least one sensor signal is generated, and - from the at least one sensor signal is closed in an identification step on the identity of the material.

2. Method according to the preceding claim, wherein before the pyrolysis step the material is subjected to at least one further thermal treatment step, in particular at least one evaporation step, whereby volatile

Components of the material are at least partially removed from the material.

3. The method according to the preceding claim, wherein in the further thermal treatment step see a temperature between 50 ⁰ C and 200 ⁰ C is used, in particular a temperature between 100 ° C and 150 ⁰ C.

4. The method according to one of the two preceding claims, wherein the further thermal treatment step for a period of between 1 minute and 2 hours, in particular for a period of one hour, is performed.

5. A method according to any one of the preceding claims, wherein the supply of the characteristic material to the surface wave sensor (138; 212) is effected by means of at least one carrier gas.

6. The method according to any one of the preceding claims, wherein in the pyrolysis step at least one temperature treatment is carried out at a temperature of at least 500 ° C, preferably in a range between 550 ° C and 900 ⁰ C, more preferably between 600 ° C and 650 ° C.

7. The method according to any one of the preceding claims, wherein after the pyrolysis step, the characteristic material is subjected to at least one cooling step to condense low volatiles.

8. The method according to any one of the preceding claims, wherein in the identification step, at least one marker material of the material is sought.

9. The method of claim 1, wherein at least one database of sensor signals of a plurality of characteristic materials is used.

10. The method according to any one of the preceding claims, wherein in the identification step, a correlation method is used.

1 1. Use of a method according to any one of the preceding claims for distinguishing authorized and unauthorized products, in particular petroleum products, fuels or alcohols.

12. Use of a method according to one of the preceding method claims for quality assurance, in particular for checking a concentration of an additive.

13. A device (110) for identifying a material, in particular using a method according to one of the preceding claims, comprising at least one pyrolysis device (136) for at least partial pyrolysis of the material, wherein the pyrolysis device (136) is adapted to from the

At least one characteristic material, the apparatus (110) further comprising at least one surface wave sensor (138; 212) and arranged to supply the characteristic material to the surface wave sensor (138; 212), the surface wave sensor (138; 212) is arranged to generate at least one sensor signal.

The apparatus (10) according to the preceding claim, further comprising at least one identification device (154), wherein the identification device (154) is set up in order to deduce the identity of the material from the at least one sensor signal.

15. Device (1 10) according to one of the two preceding claims, wherein the pyrolysis device (136) comprises at least one quartz tube.

16. Device (1 10) according to one of the preceding device claims, comprising at least one thermal device (1 12), wherein the thermal device (112) is adapted to subject the material before pyrolysis at least one further thermal treatment step, in particular at least one Evaporation step, wherein volatile constituents of the material are at least partially removed from the material. 3

17. Device (1 10) according to one of the preceding device claims, comprising at least one crucible (1 16) for receiving the material, in particular a stainless steel crucible.

18. Device (1 10) according to one of the preceding device claims, further comprising a piping system (1 18), wherein the piping system (1 18) to a carrier gas source (134) is connectable to the characteristic material through the piping system (1 18) the Supply surface wave sensor (138; 212).

The apparatus (1 10) of any one of the preceding apparatus claims, further comprising a triggering device (156), wherein the triggering device (156) is arranged to supply the material to the pyrolysis device (136) at a defined time.

20. Device (1 10) according to the preceding claim, wherein the triggering device (156) comprises a holding device (158), wherein the device (110) is arranged such that the material in a release of the holding device (158) in a pyrolysis position ( 164) of the pyrolysis device (136).

21. The apparatus of claim 1, wherein the at least one surface wave sensor includes a plurality of surface acoustic wave sensors, the surface acoustic wave sensors each being configured to acquire different characteristic materials detect.

22. Device (1 10) according to one of the preceding device claims, further comprising a cold trap (142), wherein the cold trap (142) is arranged to cool the characteristic material after the pyrolysis device (136) and condense low volatiles.

23. Device (110) according to one of the preceding device claims, wherein the device (1 10) as a mobile device for the mobile identification of the material, in particular as a portable handset, is configured.