Toxic Organic Vapors Research Articles

Synthesis of Indium Oxide Octahedrons for Detection of Toxic Volatile Organic Vapors

In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedronswere obtained using a simple freeze-dryingprocessfollowedby a calcination treatment. The morphology and chemical composition of the samples were investigated by field emission scanning electron microscopy (SEM), transmission electron microscopy, and X-ray diffraction (XRD). The In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> sample had an octahedron shape, a smooth surface, high crystallinity, and a particle size of approximately 4 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$ </tex-math></inline-formula> m. X-ray photoelectron spectroscopy (XPS) verified the existence of chemisorbed dissociated oxygen on the surface of the In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedrons, which has a meaningful impact on the sensing performance, leading to a high response. When used as a sensing material for volatile organic compounds (VOCs) detection, In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedrons exhibited superior sensing performance for isopropanol, ethanol, methanol, and acetone. The detection limits (LODs) of isopropanol and ethanol were 0.60 and 0.57 ppm (signal-to-noise ratio, S/N = 3), respectively. In addition, the In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedron sensor exhibited a short response, rapid recovery time, and good stability under long-term testing. The influence of the relative humidity (RH) on the In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedron sensor performance was also investigated. The outstanding sensing property of In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> octahedrons was attributed to their high crystallinity and unique morphology.

Preparation of cross-linked porous SnO2 nanosheets using three-dimensional reduced graphene oxide as a template and their gas sensing property

Semiconductor metal oxide nanostructures with large specific surface areas and high porosity will enhance their gas-sensing performance. Here, cross-linked porous tin dioxide nanosheets were obtained using three-dimensional reduced graphene oxide as a template followed by an annealing process. The as-synthesized porous SnO 2 nanosheets were composed of nanocrystals with a mean diameter of ca. 7.6 nm. The products were characterized using a range of techniques. The sensing property of the cross-linked porous SnO 2 nanosheets for toxic organic vapors, such as ethanol, acetone, isopropanol, benzene, methylbenzene, methanol, and formaldehyde, were studied. The sensor showed a high response of 37.9 for 100 ppm acetone, making it a promising candidate as a practical detector of volatile organic compounds. • A special cross-linked porous tin dioxide nanosheets were developed. • It involves a template solvothermal method and a subsequent annealing process. • The cross-linked porous SnO 2 nanosheets exhibit high sensing performance for VOCs. • High performance is due to cross-linked structure with small size nanocrystals.

External uniaxial and biaxial strains modulated adsorption behaviors of volatile organic compounds on fibrous red phosphorene

For the very first time, we investigate the sensing properties of novel monolayered fibrous red phosphorene nanosheet towards toxic volatile organic compounds using first-principles strategy. Initially, the geometric and electronic features of fibrous red phosphorene are studied. The adsorption energy, charge transfer, density of states, band structure and work function are estimated for the toxic organic vapors, benzo[α]pyrene, benzene, toluene, formaldehyde, m-xylene, o-xylene, and p-xylene adsorbed fibrous red phosphorene. It is clearly enunciated that benzo[α]pyrene chemisorbed on the surface of fibrous red phosphorene, while the other molecules physisorbed to the phosphorene. Furthermore, to understand the effect of external strain, the variations of surface assimilating attributes of benzo[α]pyrene adsorbed fibrous red phosphorene with applied uniaxial and biaxial strains are scrutinized, respectively. The results support that applying external strain is an effective strategy to modulate the sensing performance of fibrous red phosphorene towards benzo[α]pyrene.

Self-Assembled Monolayers Coated Porous SnO2 Film Gas Sensor with Reduced Humidity Influence.

Metal-oxide sensors, detect gas through the reaction of surface oxygen molecules with target gases, are promising for the detection of toxic pollutant gases, combustible gases, and organic vapors; however, their sensitivity, selectivity, and long-term stability limit practical applications. Porous structure for increasing surface area, adding catalyst, and altering the operation temperature are proposed for enhancing the sensitivity and selectivity. Although humidity can significantly affect the property and stability of the sensors, studies focusing on the long-term stability of gas sensors are scarce. To reduce the effects of humidity, 1H, 1H, 2H, 2H–perfluorooctyltriethoxysilane (PFOTS) was coated on a porous SnO2 film. The interconnected SnO2 nanowires improved the high surface area, and the PFOTS coating provided superhydrophobicity at water contact angle of 159°and perfect water vapor repellency inside E-SEM. The superhydrophobic porous morphology was maintained under relative humidity of 99% and operating temperature of 300 °C. The CO gas sensing of 5, 20, and 50 ppm were obtained with linearity at various humidity. Flame detection was also achieved with practical high humidity conditions. These results suggest the simple way for reliable sensing of nanostructured metal-oxide gas sensors with high sensitivity and long-term stability even in highly humid environments.

Luminescent and Swellable Conjugated Microporous Polymers for Detecting Nitroaromatic Explosives and Removing Harmful Organic Vapors.

Four new conjugated microporous polymers (CMPs) were synthesized by a Buchwald-Hartwig (BH) cross-coupling reaction of tri- and tetrafunctionalized precursors to yield materials with tunable surface area and pore size distribution. This approach yielded LPCMP1-4, CMPs with significantly higher Brunauer-Emmett-Teller (BET) surface areas (more than 5 times higher) than other related BH-based CMPs. These CMPs possess not only high BET specific surface areas and high chemical and thermal stabilities, but also exhibit outstanding swellability. To the best of our knowledge, swellable behavior was studied in great detail for CMPs for the first time, with the greatest degree of swelling for methanol reaching 16.5 and 16.3 mL g-1 for LPCMP1 and LPCMP3, respectively. Owing to their excellent swellability, we further studied the adsorption capacity of these CMPs for different toxic organic vapors (including toluene and methanol). LPCMP1 and LPCMP3 adsorbed 124 and 117 mg g-1 toluene, respectively, at saturated vapor pressure. For methanol, the adsorption capacities of LPCMP1 and LPCMP3 were up to 250 and 215 mg g-1, respectively, which are the highest recorded values when compared with published data for CMPs, HCPs, MOFs, and porous carbons. These materials are promising candidates for the removal and elimination of hazardous organic vapors and chemical warfare agents. Moreover, all the polymers show high sensitivity to nitroaromatic explosives. LPCMP2 and LPCMP4 exhibit high selectivity for TNT and may be suitable as new candidates to selectively detect TNT for security or environmental applications.

Adamantane-Based Micro- and Ultra-Microporous Frameworks for Efficient Small Gas and Toxic Organic Vapor Adsorption.

Microporous organic polymers and related porous materials have been applied in a wide range of practical applications such as adsorption, catalysis, adsorption, and sensing fields. However, some limitations, like wide pore size distribution, may limit their further applications, especially for adsorption. Here, micro- and ultra-microporous frameworks (HBPBA-D and TBBPA-D) were designed and synthesized via Sonogashira–Hagihara coupling of six/eight-arm bromophenyl adamantane-based “knots” and alkynes-type “rod” monomers. The BET surface area and pore size distribution of these frameworks were in the region of 395–488 m2 g−1, 0.9–1.1 and 0.42 nm, respectively. The as-made prepared frameworks also showed good chemical ability and high thermal stability up to 350 °C, and at 800 °C only 30% mass loss was observed. Their adsorption capacities for small gas molecules such as CO2 and CH4 was 8.9–9.0 wt % and 1.43–1.63 wt % at 273 K/1 bar, and for the toxic organic vapors n-hexane and benzene, 104–172 mg g−1 and 144–272 mg g−1 at 298 K/0.8 bar, respectively. These are comparable to many porous polymers with higher BET specific surface areas or after functionalization. These properties make the resulting frameworks efficient absorbent alternatives for small gas or toxic vapor capture, especially in harsh environments.

Room-temperature BTEX sensing characterization of nanostructured ZnO thin films

ABSTRACTNanostructured zinc oxide (ZnO) thin films were deposited on glass substrates using various molar concentrations of zinc acetate dihydrate as the starting precursor at 400°C by the spray pyrolysis technique. The structural, morphological, and optical properties of the samples were investigated. X-ray diffraction studies showed thin films with a polycrystalline nature of the hexagonal wurtzite phase type. The preferred orientation was observed along the (002) direction. The crystallite size increased from 16.18nm to 20.42nm with increases in the molar concentration from 0.1M to 0.3M and then decreased further to 17.85nm at a molar concentration of 0.4M. SEM micrographs showed significant changes in the zinc oxide thin films with increases in the molar concentration of the precursor. Room-temperature Raman spectra confirmed typical electron-phonon coupling in the ZnO thin films. The optical band gap of the zinc oxide thin films was calculated using the Tauc plot. The sensitivity and selectivity of such toxic volatile organic vapors as benzene, toluene, ethylbenzene, and xylene (BTEX) were studied at room-temperature and reported.

Metal–organic framework-based nanomaterials for adsorption and photocatalytic degradation of gaseous pollutants: recent progress and challenges

Design and engineering of metal–organic frameworks for the adsorption/degradation of inorganic toxic gases, organic vapors and particulate matter.

Pristine and Carboxyl-Functionalized Tetraphenylethylene-Based Ladder Networks for Gas Separation and Volatile Organic Vapor Adsorption.

A novel tetraphenylethylene-based ladder network (MP1) made by polycondensation reaction from 4,4′,4″,4‴-(ethene-1,1,2,2-tetrayl)tetrakis(benzene-1,2-diol) and 2,3,5,6-tetrafluoroterephthalonitrile and its COOH-functionalized analogue (MP2) were synthesized for the first time. Their structures were confirmed by solid-state nuclear magnetic resonance (13C cross-polarization magic angle spinning), Fourier transform infrared spectroscopy, and elementary analysis. MP1 exhibited a high Brunauer–Emmett–Teller surface area (1020 m2 g–1), whereas the COOH-functionalized MP2 showed a much smaller surface area (150 m2 g–1) but displayed a more uniform pore size distribution. Because of the high density of nitrile groups in the network polymers of intrinsic microporosity (PIMs) and strong interaction with quadrupole CO2 molecules, MP1 exhibited a high CO2 adsorption capacity of 4.2 mmol g–1 at 273 K, combined with an isosteric heat of adsorption (Qst) of 29.6 kJ mol–1. The COOH-functionalized MP2 showed higher Qst of 34.2 kJ mol–1 coupled with a modest CO2 adsorption capacity of 2.2 mmol g–1. Both network PIMs displayed high theoretical ideal adsorbed solution theory CO2/N2 selectivities (51 and 94 at 273 K vs 34 and 84 at 298 K for MP1 and MP2, respectively). The high selectivities of MP1 and MP2 were confirmed by experimental column breakthrough experiments with CO2/N2 selectivity values of 23 and 45, respectively. Besides the promising CO2 capture and CO2/N2 selectivity properties, MP1 also demonstrated high sorption capacity for toxic volatile organic vapors. At 298 K and a relative pressure of 0.95, benzene and toluene sorption uptakes reached 765 and 1041 mg g–1, respectively. Moreover, MP1 also demonstrated some potential for adsorptive separation of xylene isomers with adsorptive selectivity of 1.75 for m-xylene/o-xylene.

Ultramicroporous Carbons Derived from Semi-Cycloaliphatic Polyimide with Outstanding Adsorption Properties for H2, CO2, and Organic Vapors

Ultramicroporous carbons (UMC-Ts) have been successfully prepared using nitrogen- and oxygen-rich porous semicycloaliphatic polyimide as a precursor in the presence of KOH at different carbonization temperatures of 600, 700, and 800 °C, respectively. The evolution of porous and chemical structures of the resultant carbons in the course of carbonization as well as their effects on adsorption of H2, CO2, benzene, and cyclohexane are studied in detail. Compared with the porous polyimide precursor, after carbonization treatment, the products exhibit the significantly increased BET specific surface areas from 900 to 2406 m2 g–1 and create large amounts of ultramicropores with the pore size smaller than 0.5 nm, leading to outstanding adsorption capacities for CO2 (34.0 wt %, 273 K/1 bar) and H2 (3.7 wt %, 77 K/1 bar). Moreover, it is interesting to observe that UMC-Ts possess extraordinarily large uptake for benzene (74.4 wt %, 298 K) and cyclohexane (64.8 wt %, 298 K) at the very low relative pressure (P/P0 = 0.1), showing promising applications in CO2 capture, H2 storage, and removal of toxic organic vapors.

The cost-effective synthesis of furan- and thienyl-based microporous polyaminals for adsorption of gases and organic vapors.

This work reveals that furfural and 2-thenaldehyde can readily react with melamine via "one-step" polycondensation to yield hyper-cross-linked sulfur-, nitrogen- and oxygen-rich microporous polyaminals with promising applications in adsorption of gases and toxic organic vapors.

Monodispersed ultramicroporous semi-cycloaliphatic polyimides for the highly efficient adsorption of CO2, H2and organic vapors

Monodispersed ultramicroporous semi-cycloaliphatic polyimides (sPIs) were synthesizedviasolution polycondensation and possess high uptakes for CO2, H2, aromatic and aliphatic vapors, exhibiting potential in gas storage and the recovery of toxic organic vapors.

Microporous polyimides with functional groups for the adsorption of carbon dioxide and organic vapors

Microporous polyimides containing a high density of trifluoromethyls or benzophenone with uniform pores are synthesized, which possess high uptakes for CO2and aromatic and aliphatic vapors, exhibiting potential in gas storage and recovery of toxic organic vapors.

Micro- and mesoporous poly(Schiff-base)s constructed from different building blocks and their adsorption behaviors towards organic vapors and CO2gas

Four porous poly(Schiff-base)s, PSN-DA, PSN-TAPB, PSN-TAPA and PSN-TAPM, are synthesized via one-pot condensation from 1,3,5,7-tetrakis(4-formylphenyl)adamantane with rod-like m-phenyldiamine, triangular 1,3,5-tris(4-aminophenyl)benzene and tris(4-aminophenyl)amine as well as tetrahedral tetrakis(4-aminophenyl)methane, respectively. It is found that the variation of the geometrical shape of the building blocks significantly alters the surface areas, pore sizes and distributions of the resultant porous polymers and thereby remarkably influences their adsorption behaviors towards organic vapors and CO2 gas. PSN-DA, PSN-TAPB and PSN-TAPA are microporous materials with pore sizes of 0.72, 0.95 and 1.04 nm, whereas PSN-TAPM is a micro- and mesoporous material with the major pores centered at 0.86 and 2.62 nm, respectively. Their BET surface areas are in the range from 419 to 1045 m2 g−1. At P/Po = 0.9 and 298 K, PSN-DA possesses high uptakes for both aromatic vapor (benzene, 86.1 wt%) and aliphatic vapor (cyclohexane, 77.9 wt%). In addition, the adsorption and desorption isotherms of CO2 gas in the four porous polymers are reversible – a characteristic which is convenient for the regeneration of CO2 adsorbents. Their adsorption capacities of CO2 are up to 15.0 wt% (273 K/1 bar) with the ideal selectivities of CO2/N2 and CO2/CH4 up to 71 and 14, respectively. showing potential applications in the removal of toxic organic vapors and capture of CO2 from air.

Aluminum sheet-based S-doped TiO2 for photocatalytic decomposition of toxic organic vapors

S-doped TiO2 (S-TiO2) films were immobilized on flexible low-cost aluminum sheets (S-TiO2-AS) using a sol-gel dipping process and low post-processing temperatures. The photocatalytic degradation of toxic organic vapors using the prepared films was evaluated using a continuous-flow glass tube under visible light exposure. The surface properties of the S-TiO2-AS and TiO2-AS films were examined by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and ultraviolet-visible spectroscopy. The photolysis of benzene, toluene, ethyl benzene, and xylene (BTEX) did not occur on the bare AS. In contrast, the photocatalytic degradation efficiencies of the target pollutants using S-TiO2-AS were higher than those obtained using reference TiO2-AS photocatalyst. In particular, the average photocatalytic degradation efficiencies of BTEX using S-TiO2-0.8-AS (S/Ti ratio = 0.8) over a 3-h process were 34%, 78%, 91%, and 94%, respectively, whereas those of TiO2-AS were 2%, 11%, 21%, and 36%, respectively. The photocatalytic decomposition efficiencies of BTEX under visible irradiation using S-TiO2-AS increased with increasing S/Ti ratios from 0.2 to 0.8, but decreased when the ratio further increased to 1.6. Thus, S-TiO2-AS can be prepared using optimal S/Ti ratios. The degradation of BTEX over S-TiO2-AS depended on the air flow rates and initial concentrations of the target chemical. Overall, under optimal conditions, S-TiO2-AS can be effectively applied for the purification of toxic organic vapors.

Naphthalene-Based Microporous Polyimides: Adsorption Behavior of CO2 and Toxic Organic Vapors and Their Separation from Other Gases

Naphthalene was selected as a building block to prepare three polyimide networks with different topological structures via one-pot polycondensation from naphthalene-1,4,5,8-tetracarboxylic dianhydride with tetrakis(4-aminophenyl)methane, tris(4-aminophenyl)amine, and 1,3,5-tris(4-aminophenyl)benzene. The resultant polymers have moderately large BET surface areas with narrow pore size distribution at around 6 A. Interestingly, it is found that they can uptake 90.5 wt % benzene vapor (298 K, 0.8 bar), and the separation factors of benzene over nitrogen, water, and cyclohexane are as high as 759.3, 40.3, and 13.8, respectively. The high adsorption capacity and selectivity of benzene vapor are attributed to the incorporation of large amount of naphthalene groups in the network since naphthalene is highly hydrophobic in nature and has strong π-electron-delocalization effect. On the other hand, the CO2 uptakes in polymers reach 12.3 wt % (273 K, 1 bar), and the adsorption curves are reversible. Moreover, the se...

Feasibility Study on Laser Cutting of Phenolic Resin Boards

Laser cutting is the most widely implemented application of lasers in industry. The many advantages of this process stimulate users in industry to cut many different materials, such as wood and wood composites –particleboard, plywood, etc.–, which are being cut with excellent results and productivity. Phenolic resins boards are a new substitute of wood in highly aggressive environments. In the present work we study the feasibility of CO2 lasers to cut phenolic resin boards and assess the potential health hazards of the vapours and residues produced, since its thermal degradation may produce toxic organic vapors.

Estimating Service Lives of Air-Purifying Respirator Cartridges for Reactive Gas Removal

A mathematical model has been developed to estimate service lives of air-purifying respirator cartridges that remove gases reactively from flowing air. Most gases, because of their high volatility and low polarizability, are not effectively removed by physical adsorption on activated carbon. Models previously developed for toxic organic vapors cannot estimate service lives of cartridges for toxic gases. Often, an activated carbon is impregnated with a chemical to enhance gas removal by chemical reaction(s). The kinds of reactions, types and amounts of impregnants, and effects of the presence of water vary; therefore, the model requires user inputs of gas capacity and water effect parameters. Ideally, these should be available from manufacturers of the cartridges. If they are not, they can be extracted from measured breakthrough times using this model. The key to this model is the observation that adsorption rates of gases can be adequately quantified by the same correlations that have been reported for organic vapors. The resulting model has been used to correlate and predict breakthrough times for several common toxic gases.

Determination of the diffusion coefficient of some highly toxic organic substances by using a diffusion tube CA Hemijska industrija

The determination of specific characteristics of materials commonly used in the preparation of cloths for the protection of the human body, lungs and other human organs, based on the principles of the effective adsorption of highly toxic organic vapors initially requires the development of specific and reliable techniques for the preparation of a gas stream with the relevant highly toxic organic substances. The dynamic method, one of the techniques commonly used for material characterization, is based on the procedure of determining the concentration of different substances in the gas stream at the inlet and after passing through a specific thin layer of the adsorption material (outlet). Therefore, the generation of a gas phase containing highly toxic organic substances in a defined quantity during a specific time interval, is the requirement that must previously be fulfilled before using the dynamic method for testing specific materials for protection of the human body. Usually, a dynamic method of determining the quality of cloths prepared with specific adsorbents requires a relatively low volumetric flow rate of the gas phase containing the test substance which may be achieved by using a diffusion tube (DT) as the standard equipment for the generation of test substances. A very wide range of concentrations of the test substances in a specific gas phase (inert, air) can be obtained by varying the working conditions (temperature, pressure, gas flow rate) and the geometrical size of the diffusion tube, taking into account that the concentration of toxic substances, is determined as the ratio of their diffusion rate and from the DT and the carrier gas flow rate. The diffusion rate of the test substances from the DT is caused by the concentration gradient between the partial pressure of the saturated vapor at one end of the DT capillary and the partial pressure at the outlet of the diffusion tube according to Fick's law. The mass rate of the generated test substances from the DT is constant for constant conditions (temperature and pressure) in the reservoir of the DT On the basis of a detailed theoretical calculation such a rate (R) may be defined by the equation: R = 16.624 DM(P/T)(A/L)log [P/(P- pv)l, mg/min where: D - the diffusion coefficient, cm/s; M - the molar mass of the test substance, g/mol; P - the pressure in the DT kPa; pv - the vapor pressure of the test substance, kPa; A - the cross sectional area of the capillary of the DT cm2: L - the length of the capillary of the DT cm; T - the temperature, K. A procedure for the constant isothermal vapor generation of hydrogen cyanide (HCN) and 2-bromo-2-chloro-1,1,1-trifluoroethane (halotane) into air by a using diffusion tube is described. The DT was placed into a thermostat 0.5?C) and the diffusion rates of the substance were measured during some time interval and the above equation was used for the determination of the diffusion coefficient. The obtained data were correlated with the calculated ones on the basis of an empirical correlation from the literature. The relative differences in the experimentally determined and theoretically calculated values of the diffusion coefficient for hydrogen cyanide at different temperature (19-23.2?C) were 26-31 % and for halotane (26-45?C) 8-14%.

Development of a process for removal of organic solvent vapors from ventilation exhaust of wood-working plants

UDC 66o074.5.081.3.0 97/)01.5 Ventilation exhausts from wood-working plants contain hazardous organic vapors, the total concen~ation of which often fluctuates within the range 0.4-1 g/m 3. Such concentrations are insufficient for realization of the thermocatatytic method in the self-heating regime typically used for removal of these compounds from exhausts (without self-heating, the energy consumptior~ for heating the exhausts makes application of the method economically inexpedient). Earlier [1] we investigated the feasibility of preconcentration of toxic organic solvent vapors on catalysts wkich are simultaneously sorbents. Taking into account the data obtained, let us consider the feasibility of preconcentration of organic vapors contained in ventilation exhausts by the method of adsorption followed by desorption and catalytic comp!ete combustio~ In order to ensure optimal total concentration of the organic compounds at the h~Aet to the catalytic reactor (4-15 g/m3), we investigated the choice of adsorbents, determination of the adsorption parameters~ and the optimal desorptio~ conditior.g. We studied the processes of absorption, desorption, and catalysis on model gas mixtures on a continuous-flow ~boratory apparatus consisting of three basic units: 1) a system for preparation of vapor and gas mixtures includhag a~ air compresso:, regulating valves, rheometers, a mixer, and gas hflets; 2) an adsorption-desorption unit (AD unit) consisting of adsorbers able to operate in the adsorption-desorption regime, an electric heater for the air, ~o laboratory autotransformers for regulation of the voltage supplied to the electric heater for the air and adsorber wall heater; 3) a catalytic unk contaLnmg a reactor heared by a tubular electric furnace and a laboratory autotransformer for regulation of the temperature in the furnace. The temperature was determined using a thermocouple at different points of the adsorbent beds in the adsorber and the catalyst in the reactor and fixed by the KSP-4 potentiometer. Upon passage of an air flow through the system for preparation of the stream and gas mixtures, a content of the organic vapors close to the real values obtained from data examining ventilation exhausts from wood-working plants is provided. The concentrations of the organic compounds in the air flow supplied to the AD u~it are presented below.