The present invention relates to a hydrocarbon adsorbent with metal-impregnated zeolite particles having regular mesopores and a manufacturing method therefor. The hydrocarbon adsorbent includes a metal cation and a metal oxide that are impregnated in zeolite particles, in particular, the zeolite particles include regularly formed mesopores having a size of 2 to 10. By adjusting a Si/Al ratio and mesoporosity of the mesopores, a hydrocarbon adsorbent may have increased adsorption capacity for hydrocarbons in a cold-start section and can rapidly oxidize the hydrocarbon upon desorption thereof, thereby reducing the discharge of exhaust gas produced in automobiles and industries.

A gas purification processing apparatus is described. The gas purification processing apparatus can control the generation of adsorption heat by an adsorbate substance in purification processing and thereby prevent desorption or ignition or the like of the adsorbate component by performing cooling processing on an adsorbent itself when needed. This advantageously ensures high adsorption efficiency with a simple and convenient configuration. During operation of the apparatus, gas is supplied from the source and purified by a purification part and then discharged as a purified gas. When the temperature of the purification part exceeds a predetermined temperature, a cooling medium is supplied from the cooling processing part to cool the purification part.

Hybrid thermal oxidizer systems and methods for combusting waste gas and heating utility oil using an efficient transfer of heat from fuel gas. The hybrid thermal oxidizer includes a combustion chamber, a gas preheater and a quench chamber positioned between the combustion chamber and the gas preheater. The combustion chamber burns impurities in the waste gas to produce an exhaust gas. The gas preheater preheats the waste gas before burning impurities in the combustion chamber. And, the quench chamber controls a temperature of the exhaust gas before preheating the waste gas.

A method for densifying one or more porous substrates with pyrolytic carbon by chemical vapour infiltration, includes admitting, at the inlet of the densification furnace, a reactive gaseous phase including at least one pyrolytic carbon precursor; reacting at least a fraction of the reactive gaseous phase with the porous substrate or substrates; extracting, at the outlet of the densification furnace, gaseous effluents originating from the reactive gaseous phase; reintroducing, with the reactive gaseous phase admitted at the inlet of the densification furnace, at least a fraction of the gaseous effluents extracted at the outlet of the furnace, wherein the fraction of the gaseous effluents introduced with the reactive gaseous phase includes at least one polyaromatic hydrocarbon compound.

The present disclosure provides a process for cleaning raw product gas. The process includes contacting the raw product gas with a flow of catalyst to reform organic contaminants and inorganic contaminants in the raw product gas and to remove particulates. Further, the process includes cooling the resulting product gas via heat exchange with a heat exchange medium in the presence of char or a solid adsorbent medium to condense remaining organic contaminants and inorganic contaminants on the char or solid adsorbent medium and to filter out fine particulates.

Disclosed in certain embodiments are methods of removing water from a gas feed stream comprising hydrocarbons and water during an adsorption step of an adsorption cycle.

A purifying device for purifying a process fluid that flows in a dehumidifying plant for dehumidifying plastics includes a first layer configured for filtering the process fluid, and a second layer configured for reducing, by adsorption, substances that are harmful for health, in particular COV/SOV, which are present in the process fluid.

The present invention relates to a zeolite-based adsorbent comprising at least one zeolite of FAU structure of LSX type and comprising barium and/or potassium, in which the outer surface area of said zeolite-based adsorbent, measured by nitrogen adsorption, is between 20 m.sup.2.Math.g.sup.−1 and 100 m.sup.2.Math.g.sup.−1, limits inclusive. The present invention also relates to the use of such a zeolite-based adsorbent as an adsorption agent, and also to the process for separating para-xylene from aromatic isomer fractions containing 8 carbon atoms.

A filtering device is provided for filtering pollutants from a gas stream. The device includes a cartridge comprising an inner perforated passage, an outer perforated jacket, one or more non-perforated ends and a sorbent bed contained between the inner passage and the outer jacket; and a outer shell containing the cartridge and having a first port in fluid communication with the inner perforated passage and a second port in fluid communication with the outer perforated jacket. A flowpath of the gas stream into any one of the first port or the second port, through the sorbent bed and out of the other of the first port or the second port is a bidirectional flowpath. A method is further provided for filtering pollutants from a gas stream. The method includes the steps of allowing the gas stream to flow into a filtering device in a first direction, the device comprising a cartridge having a sorbent bed contained therein; directing the gas stream to bend in a second direction differing from the first direction as it enters the sorbent bed; and allowing the gas stream to pass through the sorbent bed and to exit the device.

The invention relates to a method for producing dinitrotoluene, comprising the following steps: a) nitrating toluene with a mixture of nitric acid and sulfuric acid and subsequently separating a sulfuric-acid-containing aqueous phase that arises in the nitration, wherein a raw dinitrotoluene is obtained, b) washing the raw dinitrotoluene in a water wash with neutral and/or alkaline washing water, wherein a pre-cleaned dinitrotoluene, which contains at least water in addition to dinitrotoluene, is obtained after the washing water used in the last wash has been separated, and c) separating the water from the pre-cleaned dinitrotoluene, d) collecting the waste water from steps a), b), and/or c), e) optionally extracting the collected waste water from step d) with toluene and returning the thus obtained organic phase to step a), f) freeing the collected waste water from step d), or, if the optional step e) is performed, the extracted waste water from step e), of toluene in a toluene stripper, wherein a toluene-containing exhaust gas flow is obtained, g) feeding at least one exhaust gas flow from steps a), b), c), d), e), or f) into an exhaust gas condenser and removing the toluene contained in the at least one exhaust gas flow in said exhaust gas condenser, wherein the method comprises the following further step: h) feeding the exhaust gas flow arising in step g) after the condensing out of the toluene to a thermal exhaust air cleaning, wherein nitrogen is added to the exhaust gas flow to be fed to the exhaust gas condenser or to the exhaust gas flow leaving the exhaust gas condenser, wherein preferably a nitrogen concentration in the exhaust gas flow of at least 0.1 vol % is set, especially preferably of at least 0.5 vol %.