Abstract: The present invention relates to an air filtration system and a method for making a photocatalytic oxidation substrate by powder coating a photocatalyst onto a metal substrate.

Abstract: The present invention relates to an air filtration system and a method for making a photocatalytic oxidation substrate by powder coating a photocatalyst onto a metal substrate.

Abstract: The invention relates to a method for the enzymatic production of a curing agent in its fluid state, e.g. liquid, comprising, in free phase, at least one oxygenated chemical species. Said method consists in bringing into contact at least one enzymatic catalysts agent, comprising at lease one peroxidase-type enzyme; an oxidizable substrate in aqueous phase that can be oxidized by the action of an oxygen donor, by catalysis by said enzymatic catalysis agent, generating said oxygenated chemical species in free phase; and said oxygen donor.

Abstract: A photocatalytic substance whose photocatalytic efficiency is greatly strengthened by making an improvement over titanium dioxide on which micron-size fine metal particles are supported, a base material which holds this photocatalytic substance, and manufacturing methods therefor. By reducing the mean particle diameter of metal particles from the size of fine metal particles on the micron scale to the size of ultra-fine metal particles on the nano-scale, it was succeeded that the photocatalytic efficiency of photocatalytic substances such as titanium dioxide, etc. was greatly strengthened. In particular, the feature is that the particle diameter of the ultra-fine metal particles used is set in a range which allows the conspicuous manifestation of a quantum size effect, and the mean particle diameter is in the range of 1 to 10 nm.

Abstract: Gases containing hydrogen cyanide, ammonia and hydrogen sulfide are purified by first washing the gas with a suspension of solid sulfur to fix the hydrogen cyanide as ammonium thiocyanate and ammonium thiosulfate. The resulting suspension is then subjected to a wet-oxidation wherein the thiosulfate and a part of the thiocyanate is converted into sulfuric acid and ammonium sulfate afterwhich the resulting liquid containing unreacted thiocyanate is decomposed into an ammonium salt and is recovered from the oxidation and decomposition steps.