DE19831313A1 - Quantitative and qualitative determination of absorbed pollutant substances by monitoring electrical properties of a substrate during controlled thermal desorption - Google Patents

Abstract

A sensor for quantitative and qualitative determination of substances absorbed / adsorbed on a substrate (1) from an aqueous or gaseous flow (8) has a substrate made of a fiber, woven , felted or tangled filament web of semiconducting material and/or activated carbon, capable of electrical resistance heating when energized from an external circuit (4,5,6). An Independent claim is also included for a process of identifying and quantifying pollutant species by monitoring such properties as electrical conductivity, capacitance, and temperature during timed thermal desorption from an absorbent substrate. The substrate is contained so that the contaminated flow either impinges upon, or passes through it, and has an average pore size of the order of less than 50 nm. Operating temperatures are -200 to +1000 deg C. The substrate is preferably water wettable , but may be impregnated with a lipophilic material such as silicon oil. Catalytic materials such as alkali metal or alkaline earth metal iodides, noble metal, transition metal complexes, salts or porous elemental forms may be incorporated into the substrate; near group VIII metals are particularly preferred.

Description

The present invention relates to a sensor, the use thereof, in particular for measurement and regulation of substances in aqueous and gaseous fluids and / or aerosols, and Method for determining the type of sorbate and the sorbate loading of the sensor. Further The present invention relates to filter elements which contain such sensors and suitable ones Uses for this, as well as a method for determining the type of sorbate and the Sorbate loading of the filter element.  

Sensors for determining substances contained in fluid are known. For example there is electronic devices for the determination of ethanol, CO and other gases. These sensors have the disadvantage that they are only used for the qualitative or quantitative measurement of are suitable for certain substances. In addition, the quantitative determination is mostly only insufficient. In particular, the quantitative and / or qualitative determination of Process gases or the like in the ppb range only with means that are very complex in terms of equipment possible. These known systems are technically complex and therefore require a large one technical effort in the production. It should also be added that those in the prior art Known sensor systems are not used anywhere because of their space requirements can be.

Gaseous and aqueous fluids, for example process gases and vapors, often contain toxic or polluting pollutants. To protect people and the environment Usually filter elements are used to remove such pollutants from aqueous and gaseous ones Remove fluids, which are then disposed of properly.

It is known that the respective proportions of substances in the fluids can vary considerably. A Determination of the content and composition of the pollutants of the respective fluid flow however mostly not or only with technically very complex sensor systems, especially with one continuous measurement, possible.

In the known filter elements, it has proven to be very disadvantageous that in particular Changes in the pollutant content in fluids often load the filter element with sorbate cannot be estimated or can only be roughly estimated. A major disadvantage of the known filter systems is that the exact time when such filter elements are exchanged or regenerated must be d. H. the time of the maximum loading of the filter element with sorbate, cannot be determined exactly but must be estimated. This leads to one Exchange cycles for filter elements within which the filter elements are independent of actual load state are exchanged. One in the prior art widespread procedure leads to filter elements being replaced early.  

No further explanation is required here that such a routine exchange for a Waste of material leads because filter elements are still active in ignorance of the actual Loading condition can be replaced early. There is also a risk that at premature exhaustion of the filter element toxic substances are released into the environment, because the actual loading condition of the filters commonly used in the prior art is not controlled.

Another disadvantage of the filter systems known in the prior art is that there are none Receives information about which substances the filter is loaded with. This is for example at Proper disposal is disadvantageous, since the filters could contain substances Regeneration of the filter or special disposal of the filter Need treatment.

In addition, the filter elements cannot be optimized for the respective place of use because for this neither the time-dependent loading state nor the loading of the filter element with knows certain substances that should be retained.

It would therefore be very desirable to have a sensor and filter elements containing one To make available sensor that has all the aforementioned disadvantages in the prior art overcomes and can be manufactured without great expenditure of time and material.

The object of the present invention is, in particular, the aforementioned disadvantages and shortcomings to overcome the state of the art. This object is achieved by the present invention solved by a sensor for fluids, the at least one through which the fluid can flow and / or Flowable surface made of an adsorbing and / or absorbing material for absorption of sorbate, as well as electrical contacts to which an electrical voltage can be applied from the outside, has, the flow-through and / or flow-through surface optionally with Holding members and / or shaping means is provided to stabilize them.  

Further advantageous embodiments of the present invention are in the Subclaims listed and can be found in the accompanying figures.

A flowable and / or flowable area in the sense of the invention can be preferably also use one or more threads advantageously.

The sensor may have several, preferably 1 to 100, particularly preferably 1 to 5 flowable and / or flowable surfaces and / or threads.

It is advantageous if one or more of the flowable and / or flowable Surfaces and / or threads each have one or more electrical contacts attached. To this electrical contacts, an electrical voltage can be applied from the outside, so that then the electrical voltage either at one and / or at several of the flowable and / or flowable surfaces and / or threads.

The flowable and / or flowable surfaces and / or threads are partially or made entirely of an adsorbent and / or absorbent material.

The material that can be used according to the invention is preferably wettable with water have narrow pore radius distribution, and has a temperature-dependent electrical Resistance coefficients. Suitable pore radius distributions are for non-impregnated ones adsorbing and / or absorbing materials in the range of ≦ 0.2 nm and especially below ≦ 0.1 nm. For adsorbent and / or impregnated with precious metals absorbent materials, the pore radius distribution is preferably in the range of 0.2 to 50 nm. Of course, depending on the requirement profile, the pore radius distribution d. H. depending on the type of loading of fluids, also <0.2 nm or even <50 nm his. The material which can be used according to the invention particularly preferably has a spatial configuration uniform electrical conductivity.  

Further materials that can be used according to the invention include all materials that are used ohmic heating can be heated to a temperature at which the adsorbed and / or absorbed Sorbate can be driven out.

The electrically conductive adsorbing and / or absorbing material is preferably made of a porous metal, semiconductor and / or activated carbon, particularly preferably activated carbon fabric, Activated carbon knitted fabric, activated carbon felt, activated carbon fiber strand, activated carbon fiber material and / or Activated carbon extrudate. It is particularly advantageous that activated carbon is an ohmic heating conductor. Activated carbon is advantageously characterized by very low material costs, non-toxicity, d. H. the lack of a potential hazard; long durability, low heat capacity, and a temperature-dependent electrical resistance coefficient (α: 3-4% [1 / K]). In addition, activated carbon is practically not sensitive to atmospheric moisture in the area below approx. 70-80% RH (relative humidity), d. H. Activated carbon has a low Cross sensitivity to relative air humidity or water loading on couches Humidity above this range before, activated carbon is extremely advantageous suitable for example by continuous heating, by means of a constant electrical current to reduce the water load.

It has been found that at high fluid flow rates it is advantageous if the Sensor, in particular the adsorption and / or absorption surface (s) by holding members and / or shaping agents can be stabilized in order to avoid mechanical damage.

An advantageous embodiment of the invention provides that the holding members and / or Shaping means are at least partially electrically conductive, so that they are electrical Contacts can serve. In this way, an external electrical voltage can be applied to the adsorbent and / or absorbent material can be applied by the holding members and / or Shaping means are contacted with the external electrical voltage source.  

It has been shown that the use of threads over large-area ad and / or Absorption surfaces as a probe has special advantages, because when using threads the Manufacturing simplified and only a lower use of materials is necessary. Due to the Such a small area requires less space and is practical at every conceivable location, the pipe systems, filters, work rooms and the like include usable. In addition, when using threads, the heat is dissipated via the electrical contacting or holding members and / or shaping means particularly low, d. H. you get a good signal / noise ratio.

In a further advantageous embodiment, the sensor has a cylindrical envelope which comprises an inlet opening exposed to the fluid flow and an outlet opening, wherein the inlet opening can be equal to the outlet opening.

In a preferred embodiment, the cylindrical sheath has an electrical one Contact with the adsorbing and / or absorbing material and is with electrical Provide contacts to which an electrical voltage or current source can be applied from the outside. In this way, an external electrical voltage to the adsorbent and / or absorbent material are applied. For mechanical reinforcement are in a further suitable embodiment at the inlet and / or outlet openings the cylindrical cladding grid, preferably metal grid, plastic grid and / or the like arranged.

In an advantageous embodiment, the adsorbent and / or absorbent material impregnated the sensor with catalytically active substances. According to the invention advantageous usable substances include ionic and / or polar complex compounds, preferably selected from the group of alkali and / or alkaline earth metal salts, and particularly preferably their iodides. Other preferred substances include metals and Metal compounds such as transition metals, noble metals or the like. In particular are Metals and / or metal compounds of subgroup VIII and / or complex compound (s),  and salts of the abovementioned substances which have catalytic properties, prefers.

If here z. B. the detection of mercury is provided, the transition metals, which is preferably chosen within the second and third rows of the periodic table become a good solubility, d. H. a solubility of up to about 100% for mercury.

It can also be advantageous that the adsorbing and / or absorbing material of the sensor according to the invention is impregnated with a lipophilic substance, preferably silicone oil, to improve the adsorption and / or absorption of lipophilic substances in the fluid stream, or to to suppress the adsorption and / or absorption of hydrophilic substances.

A suitable embodiment of the sensor is the use as a "broadband" sensor. Here are suitably a plurality of flowable and / or flowable surfaces and / or threads arranged in the sensor. It is preferred if one or more of the flowable and / or flowable surfaces and / or threads partially and / or completely the same or have different impregnation (s). Such an arrangement enables Dependence of the adsorbable and / or absorbable substances of the respective fluid flow specific adsorption and / or absorption on the adsorbent and / or absorbent material to optimize the sensor. Such an optimization step can be quantitative and qualitative Improve the determination of the different substances contained in the fluid.

An equally preferred embodiment provides that the preferably large area adsorbent and / or absorbent material is wettable, whereby in particular amount and Type of adsorbable and / or absorbable substances of finely dispersed fog droplets, so-called aerosols can be determined.  

In yet another preferred embodiment, the sensor is in a filter or Filter element arranged. Filter elements that contain the sensor according to the invention exist preferably of an adsorbent and / or absorbent material, such as a porous one Metal, semiconductors, especially activated carbon. Preferred activated carbon materials include Activated carbon fabrics, activated carbon knits, activated carbon felts, activated carbon fiber strands, Activated carbon fiber materials and / or activated carbon extrudates. It is particularly preferred here if the adsorbing and / or absorbing material of the filter element is of the same type Material such as the adsorbent and / or absorbent material of the adsorption sensor.

It is of course easily possible, and also particularly advantageous if in one Filter element several sensors according to the invention are arranged.

The sensor (s) according to the invention can advantageously in the front, ie. H. that of the inflow surface nearby filter section, in the middle, d. H. between the inflow and outflow surface centrally located filter section and / or in the terminal filter section, d. H. that of Outflow surface nearby filter section, may be arranged.

In a conceivable embodiment, the sensor is in the range of the largest sorption rate of the Sorbate of the fluid flow, the so-called mass transfer zone.

One embodiment of the sensor according to the invention provides for measuring the temperature of the adsorbing and / or absorbing material, a thermocouple, which is preferred is arranged on the adsorbing and / or absorbing material of the sensor.

In addition, a sensor with an electrical measuring device for determining the electrical properties, in particular the electrical conductivity of the adsorbent and / or absorbent material.  

If necessary, and preferably when using large-area adsorption and / or Absorption surfaces, the sensor has an additional connecting element for forwarding the Desorbate on devices for downstream analysis of desorbate, such as on a Mass spectrometer, a flame ionization detector, a thermal conductivity detector and / or the like.

The sensor according to the invention is for determining the adsorbable and / or absorbable Substances from fluids and / or aerosols, in particular from process gases and the like, suitable. In addition, the sensor according to the invention can be used to determine the load and sorbate type of filter elements. In a particularly advantageous manner, by means of the sensor according to the invention, several substances and their respective fluid loads, and determine the sorbate types and loads of filter elements. The filter elements can z. B. as a vehicle cabin filter, clean room filter in the electronics industry, filter for general exhaust air treatment, anti-corrosion filter, military filter for shelters, Vehicles and personal protection, household filters such as extractor hoods, Vacuum cleaner filter, room air filter and / or gas filter and particularly preferred as Gasoline vapor recovery filters can be used. In addition, the invention Sensor for use for monitoring purposes and / or the setting of Concentrations of substances, in particular of minimum and / or maximum concentrations Process gases suitable and / or for regulating the room air of, for example, operating sites.

The invention also relates to methods for determining the type of sorbate and / or Sorbate loading of a sensor according to the invention and / or the type of sorbate and / or Sorbate loading of a filter element, which one or more of the invention Contains adsorption sensors. This involves determining the amount and / or type of sorbate a desorption and / or phase transition of the sorbate of the adsorbent and / or absorbent material of the sensor, the desorption or phase transition of the sorbate thermally, preferably by means of electrical (ohmic) heating of the adsorbent and / or absorbent material and the desorption takes place under vacuum, if necessary.  

The desorption temperature depends on the location where the sensor is used. It understands goes without saying that the desorption temperature is related when using the sensor with liquid air or nitrogen is considerably lower than with combustion processes in the car / engine Area. The desorption temperatures can therefore be in the temperature range of -200 ° C up to 1000 ° C. Of course, the desorption temperatures can be below or above since they depend on the respective process conditions. For example, certain metals and / or metal compounds only at temperatures well above 1000 ° C in Desorb vacuum.

According to the invention, the desorption of the sorbate of the impregnated adsorbing and / or absorbing material can take place via a reversible complex formation. The desorption can also be improved via a catalytic reaction. In the case of organic substances, for example, the sorbate can be broken down via a catalyzed reaction, the reaction products thus obtained being desorbable. The impregnation is preferably carried out here with a sub-group element, in particular platinum, palladium, cobalt, nickel or copper. These form reversible complexes with CO, CO ₂ , HCN, SO ₂ and NO. The type and content of such complex-forming substances in the fluid can thus be determined by means of the sensor via the thermal decomposition of these complexes.

Suitable methods for determining the sorbate occupancy and / or the sorbate type of the sensor and / or filter element comprise a measurement of the change in the electrical properties the adsorbing and / or absorbing material of the sensor such as conductivity, in particular the differential conductivity, capacitance and / or the like, the A change in the electrical properties during the desorption of the sorbate provides the type and amount of sorbate.

Another method for determining the type and / or amount of sorbate comprises Measurement of the temperature of the adsorbing and / or absorbing material of the sensor during the thermal desorption of the sensor and / or the phase transition of the sorbate.  

The temperature is determined directly by a thermocouple and / or indirectly by the Correlation of temperature with the thermally induced change in electrical Conductivity of the adsorbent and / or absorbent material during the Desorption process measured. Activated carbon has here because of the properties of a ohmic heating conductor, proven to be particularly advantageous. Will the adsorbing and / or absorbent material for the purpose of desorbing the sorbate, preferably with constant Heating power, heated, the desorption process or phase transition of the sorbate over a decrease in the relative temperature increase of the adsorbent and / or absorbent material characterized per unit of time. Based on the characteristic non- The linear course of the temperature measurement curve determines the type and / or the amount of Sorbats. For the exact determination of the sorbate loading and / or sorbate type, the measured temperature profile over time of the adsorbing and / or absorbing material of the sensor formed the function differentiated according to time.

It should also be added that in this process the temperature measurement curve obtained in this way one is substance-specific and the other is proportional to the load on the sensor. Especially characteristic boiling / desorption temperatures result for substances in the capillary Pore system are condensed when the capillary boiling temperature (Kelvin equation) is reached becomes; in particular, the temperature effect occurring here is due to a narrow Pore radius distribution supported in its signal sharpness.

The process is preferably carried out with a relative weight loading of 0.1 to 30% of the sensor applied. The sorbate loading and / or type of sorbate of a sensor and / or Filter element which contains such a sensor is advantageously by this The process is discontinuous, but with very short dead times, preferably from 5 seconds to Measured 60 minutes.  

Another method for determining the type and / or amount of sorbate is provided in addition to Desorption of the sorbate a weighing of the adsorbent and / or absorbent material Adsorption sensor and / or the sensor during the desorption of the sorbate. To do this the weight of the adsorbent and / or absorbent material of the adsorption sensor and / or the sensor is determined by means of a quartz microbalance.

Another method sees higher in a gaseous fluid when using the sensor relative air humidity (above approx. 70-80% RH) to reduce the load on the Sensor with water a preferably constant heating of the adsorbing and / or absorbent material, preferably by a constant electric current.

Another method also sees a fluid and / or aerosol when the sensor is used before that the sensor for performing the thermal analysis from the fluid and / or aerosol Will get removed.

The invention is illustrated by the embodiment shown in the following figures further clarified.

Fig. 1 shows a schematic longitudinal section through an embodiment of the sensor according to the invention.

FIG. 2 shows a schematic cross section through the embodiment of the sensor according to the invention that is the same as FIG. 1.

According to Fig. 1, an embodiment of the sensor according to the invention is shown having a cylindrical casing in schematic longitudinal section, wherein the flow-through and / or anströmbare surface (1) consists of adsorbent and / or absorbent material. At the inflow and outflow opening of the cylindrical casing ( 2 ) is a grid, for. B. a metal grid ( 3 ) is arranged. The cylindrical sheath ( 2 ) and the flowable and / or flowable surface ( 1 ) are each provided with electrical contacts ( 4 , 5 ) to which an electrical voltage can be applied from the outside via the voltage source ( 6 ). Measuring devices ( 7 ) are provided for measuring current, voltage and other electrical measured variables. The fluid flow ( 8 ) is also shown.

According to FIG. 2, this embodiment is shown of the sensor according to the invention in schematic cross section. The cylindrical sheath ( 2 ) of the adsorbent and / or absorbent material ( 1 ) is shown in its circular cross section, the electrical contact ( 5 ) of the cylindrical sheath and the electrical contact ( 4 ) of the adsorbent and / or absorbent material as well the external electrical voltage source ( 6 ) and the measuring device ( 7 ) are shown.

Claims (27)

1. Sensor for fluids and / or aerosols, characterized in that the sensor has at least one surface through which the fluid ( 8 ) can flow and / or can flow from an adsorbing and / or absorbing material ( 1 ) for receiving sorbate, as well as electrical contacts ( 4 , 5 ), to which an electrical voltage ( 6 ) can be applied from the outside, the flowable and / or flowable surface ( 1 ) optionally being provided with holding members and / or shaping means for stabilizing them. 2. Sensor according to claim 1, characterized in that the flowable and / or flowable surface is a thread. 3. Sensor according to claim 1 or 2, characterized in that the holding members and / or shaping means at least are partially electrically conductive and preferably serve as electrical contacts. 4. Sensor according to one of the preceding claims, characterized in that the sensor several, preferably 1 to 100, particularly preferably 1 to 5, flowable and / or flowable surfaces and / or threads, with one or one or more of the flowable and / or flowable surfaces and / or threads Several electrical contacts are arranged on the outside of an electrical voltage can be applied. 5. Sensor according to any one of the preceding claims, characterized in that the sensor has a cylindrical sheath ( 2 ) with at least one inflow and outflow opening, the cylindrical sheath ( 2 ) having at least one electrical contact ( 5 ) and with the adsorbent and / or absorbent material is electrically conductive, and wherein grids ( 3 ), preferably metal grids or the like, are arranged at the inflow and outflow openings. 6. Sensor according to one of the preceding claims, characterized in that the adsorbing and / or absorbing material ( 1 ) is wettable, a narrow pore radius distribution, which for non-impregnated materials preferably in the range below 0.2 nm, particularly preferably in the range below 0 , 1 nm, for materials impregnated with noble metal is preferably in the range from 0.2 to 50 nm, and has a temperature-dependent electrical resistance coefficient and a spatially uniform electrical conductivity, the adsorbing and / or absorbing material being heated to a temperature by means of ohmic heating Range from -200 ° C to 1000 ° C can be heated, at which adsorbed and / or absorbed sorbate is driven off. 7. Sensor according to one of the preceding claims, characterized in that the adsorbing and / or absorbing material ( 1 ) comprises porous metals, semiconductors and activated carbon, preferably an activated carbon fabric, activated carbon knitted fabric, activated carbon felt, activated carbon fiber strand, Activated carbon fiber material and / or activated carbon extrudate. 8. Sensor according to one of the preceding claims, characterized in that the adsorbing and / or absorbing material ( 1 ) with a catalytically active substance such as ionic and / or polar complex compounds, preferably alkali and / or alkaline earth iodides, and also preferably with a metal , in particular transition metal, noble metal, preferably impregnated with metals from subgroup VIII and / or with complex compounds, as well as salts thereof and / or mixtures of the substances mentioned above. 9. Sensor according to claim 8, characterized in that the transition metals, preferably within the second and third row, have good solubility for mercury. 10. Sensor according to one of the preceding claims, characterized in that the adsorbing and / or absorbing material ( 1 ) is impregnated with a lipophilic substance, preferably silicone oil. 11. Sensor according to one of the preceding claims, characterized in that one or more flowable and / or flowable surfaces and / or threads are partially or completely impregnated, the respective Flowable and / or flowable surfaces and / or threads partially and / or completely have the same or different impregnation. 12. Sensor according to one of the preceding claims, characterized in that the sensor is a thermocouple for measuring the temperature of the adsorbent and / or absorbent material, which preferably on the adsorbent and / or absorbent material is arranged. 13. Sensor according to one of the preceding claims, characterized in that the sensor is an electrical measuring device for determining the electrical properties, especially the electrical conductivity of the adsorbent and / or absorbent material, and optionally a connecting element for Forwarding the desorbate to devices for analyzing the desorbate, such as a Mass spectrometer, a flame ionization detector, a thermal conductivity detector and / or the like. 14. Filter element containing the sensor according to one of the preceding claims.   15. Filter element according to claim 14, characterized in that the filter element on adsorbing and / or absorbing Materials such as porous metals, semiconductors, and preferably on activated carbon and particularly preferred on activated carbon fabric, activated carbon knitted fabric, activated carbon felt, activated carbon Fiber strand, activated carbon fiber material and / or activated carbon extrudate based, in particular preferably the adsorbent and / or absorbent material of the filter element same material as the adsorbing and / or absorbing material of the sensor. 16. Filter element according to claims 14 or 15, characterized in that one or more sensors within the filter element, in front, central and / or terminal filter section, preferably in the area of the largest Sorption rate, the so-called mass transfer zone, is arranged. 17. Method for determining the type of sorbate and sorbate loading of a sensor and / or the type of sorbate and sorbate loading. Filter elements containing one or more Sensors according to one of the preceding claims, characterized in that the desorption and / or phase transition of the sorbate of adsorbing and / or absorbing material of the sensor thermally, preferably by means of electrical (ohmic) heating of the adsorbing and / or absorbing material takes place, the amount and / or type of sorbate being determined via the temperature / time function, the desorption takes place under atmospheric pressure, high pressure or vacuum. 18. Method for determining the type of sorbate and sorbate loading according to one of the previous claims, characterized in that the sorbate and the impregnation material, preferably a sub-group element, reversible complexes formed, thermally decomposed are determined, the amount and / or type of sorbate via the temperature / time function becomes.   19. Method for determining the type of sorbate and sorbate loading according to one of the previous claims, characterized in that the change in the electrical properties of the adsorbent and / or absorbent material of the sensor such as conductivity, in particular the differential Conductivity, capacity and / or the like. During the desorption and / or phase transition is measured, with the change in electrical properties an indication of Art and provides amount of sorbate. 20. Method for determining the type of sorbate and sorbate loading according to one of the previous claims, characterized in that a measurement of the temperature, preferably via a measurement the electrical conductivity of the absorbent and / or adsorbent material of the sensor takes place during the thermal desorption of the sensor and / or phase transition of the sorbate. 21. Method for determining the type of sorbate and sorbate loading according to one of the previous claims, characterized in that weighing the adsorbent and / or absorbent Material of the adsorption sensor and / or the adsorption sensor during the desorption of the Sorbate, preferably by means of a quartz microbalance. 22. Method for determining the sorbate type and sorbate loading according to one of the previous claims, characterized in that the sensor for performing the determination of the sorbate type and Sorbate loading is removed from the fluid and / or aerosol. 23. Method for determining the type of sorbate and sorbate loading according to one of the previous claims, characterized in that in gaseous fluids of high relative humidity for Reduction of the water load of the sensor, the adsorbing and / or absorbing  Material preferably continuously, in particular by means of a constant electrical current is heated. 24. Use of the sensor according to one of the preceding claims Determination of the amount and type of adsorbable and / or absorbable substances in fluids and / or aerosols and / or the sorbate type and / or sorbate loading of filter elements containing the sensor. 25. Use of the sensor according to one of the preceding claims simultaneous determination of the quantity and type of several adsorbable and / or absorbable Substances in fluids and / or aerosols and / or sorbate types and / or sorbate types of Filterel elements containing the sensor, the sorbate types in particular by different ones Boiling point / desorption temperatures are distinguishable, and where appropriate one and / or more of the flowable and / or flowable surfaces and / or threads with impregnated different catalytically active substances. 26. Use of the adsorption sensor according to one of the preceding claims for determining the sorbate load and / or sorbate type of a vehicle cabin filter, Clean room filters in the electronics industry, filters for general exhaust air treatment, Anti-corrosion filter, military filter z. B. for shelters, vehicles and the Personal protection, household filters such. B. extractor hoods, vacuum cleaner filters, room air filters and / or gas filter, particularly preferably a gasoline vapor recovery filter. 27. Use of the sensor according to one of the preceding claims Monitoring purposes and / or adjustment of substance concentrations, especially of Minimum and / or maximum concentrations.