An exhaust gas decomposition apparatus or system that includes a bioreactor fluorine-containing compound is decomposed by contact with the first and second fluids in the bioreactor. The first fluid is supplied through a bioreactor inlet and is exhausted through the bioreactor outlet, and moves in a first direction in the bioreactor. The first or second fluid includes a biological catalyst such as an enzyme or recombinant microbe, while the other fluid includes a fluorine-containing compound. As a result, the fluorine-compounds is efficiently biologically remediated by the biological catalyst.

The present invention relates to method for converting a sulfide of the following formula (I), such as yperite: R.sup.1SR.sup.2 (I) wherein R.sup.1 and R.sup.2, identical or different, are a (C.sub.1-C.sub.3)alkyl, (C.sub.2-C.sub.3)alkenyl, aryl, aryl-(C.sub.1-C.sub.3)alkyl, or aryl-(C.sub.2-C.sub.3)alkenyl group, said group being optionally substituted by one or several groups selected from a halogen atom, OR.sup.3, and NR.sup.4R.sup.5, and R.sup.3, R.sup.4, and R.sup.5 are, independently of one another, H or a (C.sub.1-C.sub.3)alkyl; into a sulfoxide of the following formula (II): R.sup.1SOR.sup.2 (II) wherein R.sup.1 and R.sup.2, are as defined above, wherein said method comprises oxidizing the sulfide of formula (I) in the presence of a catalyst. under an atmosphere comprising dioxygen, and under white or blue light irradiation, wherein the catalyst has the following formula (I): wherein Ar.sup.1, Ar.sup.2, Ar.sup.3, and Ar.sup.4 are, independently of one another, an aryl group optionally substituted by one or several groups selected from halogen, a (C.sub.1-C.sub.3)alkyl, OR.sup.6, and NR.sup.7R.sup.8, and R.sup.6, R.sup.7, and R.sup.8 are, independently of one another, H or a (C.sub.1-C.sub.3)alkyl. The present invention relates also to an air-filtering device comprising a catalyst of formula (I).

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The invention relates to a process for the treatment of a gas stream comprising hydrochloric acid, hydrofluoric acid and fluorinated/oxygenated compounds, in which the gas stream is successively subjected to: a stage of catalytic hydrolysis; a stage of washing with an acid solution; a stage of adsorption of impurities by active charcoal; a stage of adiabatic or isothermal absorption of the hydrochloric acid in an aqueous solution, making it possible to collect hydrochloric acid solution.

A process removes substances from fluids, especially from exhaust gases of combustion plants, by contacting the fluid to be purified with Puzzolanes that contain at least 5% by weight of silicon and/or aluminum-compounds. These compounds can be dissolved away under the conditions prevailing during purification, such that they are excavated from the Puzzolanes.

The invention relates to a process for the treatment of a gas stream comprising hydrochloric acid, hydrofluoric acid and fluorinated/oxygenated compounds, in which the gas stream is successively subjected to: a stage of catalytic hydrolysis; a stage of washing with an acid solution; a stage of adsorption of impurities by active charcoal; a stage of adiabatic or isothermal absorption of the hydrochloric acid in an aqueous solution, making it possible to collect hydrochloric acid solution.

A system for recycling cooling devices, comprising a system part for catalytically oxidizing the pure hydrocarbon compounds and chlorofluorocarbons which accumulate during the recycling of the cooling devices. According to the invention, this system part comprises two reactors, provided mutually separated in the flow direction of the gases to be treated, a first reactor being used for catalytically oxidizing the pure hydrocarbon compounds while a second reactor is used for catalytically oxidizing chlorofluorocarbons.

An integrated filter material, a preparation method and an application. The filter material is composed of a commercial dust removal filter material and a catalyst that is grown on the filter material and that has a function of simultaneously decomposing nitrogen oxides and dioxins. In the preparation method, a precursor solution of manganese and cerium oxides is impregnated on the filter material, and manganese and cerium oxides are grown on the filter material by means of a chemical reaction; and vanadium oxychloride is used as a precursor of vanadium oxide and is impregnated on the filter material, reacts in water, and prepared by drying, hydrothermal and other processes. The composite filter material may remove three kinds of pollutants in flue gas at the same time, and the catalyst is firmly loaded and does not easily fall off.

A gas treatment system includes a first scrubber, a regenerative catalytic oxidizer (RCO) that treats gas that passes through the first scrubber, a second scrubber that treats the gas that passed through the regenerative catalytic oxidizer, and a dielectric barrier discharge (DBD) plasma reactor that treats the gas that passed through the second scrubber. The regenerative catalytic oxidizer includes a two-bed regenerative catalytic reactor.

Described are a catalyst, a honeycomb-type catalyst body for decomposing perfluorocompounds (PFCs), and a method of preparing the same. The described catalyst for decomposing PFCs and the method of preparing the same are as follows. Zinc as an active component for performance improvement and tungsten (W) as an auxiliary component are added to alumina selected from at least one of gamma alumina, aluminum trihydroxide, boehmite, and pseudo-boehmite, and a weight ratio of Al, Zn, and W is at 100:30 to 100:1 to 11. The catalyst for decomposing PFCs not only has an effect of having durability against fluorine generated by decomposition of PFCs but also has a synergistic effect of improving reaction activity. Furthermore, the catalyst decomposes PFCs at a lower temperature than conventional catalysts for decomposing PFCs. Thus, it is possible to reduce operating costs and secure the durability of the system during continuous operation.

Provided is a catalyst apparatus capable of removing perfluorinated compounds or nitrous oxide through a catalyst. A processing gas is introduced into a heat exchange unit, and an exhaust gas having a higher temperature than the processing gas discharged by a heat exchange action is supplied to a heating part. In the heating part, an exhaust gas capable of reacting with the catalyst may be formed through a simple temperature-raising operation, and the perfluorinated compounds or nitrous oxide are effectively removed by the catalyst unit.