A combination of bismuth oxyhalides is provided, which is a photooxidant, antibacterial and antiviral. The combination of bismuth oxyhalides is added to a filter medium (e.g., a multistage filter) to decompose VOCs and/or eliminate bacteria and/or viruses. Suitable designs of multistage filters are also provided.

Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA) comprising at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active material of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %. The present invention further relates to a process for gas phase oxidation in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active materials of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %.

The invention discloses a composite with an adsorption-visible light catalytic degradation synergistic effect and a preparation method and application thereof. The preparation method includes the specific steps that firstly, a bismuth oxyiodide/bismuth oxychloride composite nano-particle loaded activated carbon fiber composite ACF@BiOI.sub.xCl.sub.1-x is synthesized; then, the fiber surface is grafted with polyethyleneimine, and the end composite PEI-g-ACF@BiOI.sub.xCl.sub.1-x is obtained. The composite can rapidly adsorb pollutants in water, and meanwhile the pollutants are efficiently degraded with a photocatalyst loaded on the surface of the composite; besides, the purpose of recycling and reusing the photocatalyst is achieved, the comprehensive treatment capability of the composite is improved, the service life of the composite is prolonged, and the use cost is lowered.

The invention provides for a method to prepare an alumina catalyst support comprising bismuth for emission control applications, to an alumina catalyst support prepared according to the method of the invention and to an alumina catalyst support comprising bismuth and having a specific crystallinity value that leads to improved technical effects.

The invention provides for a method to prepare an alumina catalyst support comprising bismuth for emission control applications, to an alumina catalyst support prepared according to the method of the invention and to an alumina catalyst support comprising bismuth and having a specific crystallinity value that leads to improved technical effects.

Disclosed herein is a method of treating an aqueous solution containing impurities including a perfluoroalkyl substance and/or a polyfluoroalkyl substance, comprising introducing the aqueous solution into a batch or semi-batch photocatalytic reactor with a microparticulate catalyst configured to reduce chain length of the perfluoroalkyl substance and/or polyfluoroalkyl substance, forming a treated aqueous stream, the reactor including a catalyst flow controller configured to automatically increase the catalyst concentration in the reactor while agitating the catalyst-containing solution during reaction, and removing catalyst particles from the treated aqueous stream to form a purified aqueous stream. In some cases, the feed to the reactor is atomized. Corresponding systems also are disclosed.

A visible-light-photocatalyzed composite light-transmitting concrete contains several bundles of optical fibers, the optical fibers are coated with a protective layer on their outer surface, the protective layer contains a visible light photocatalyst, and the concrete has several gas-permeable pores. Such concrete is prepared by mixing a visible light photocatalyst and a light-transmitting glue, applying the mixture to the surface of optical fibers to form a protective layer, and using optical fibers in the concrete. The resulting concrete has dual properties of light transmittance and photocatalytic oxidation of gas-phase pollutants under visible light irradiation. The visible-light-photocatalyzed composite light-transmitting concrete significantly breaks through the limitation of photocatalytic concrete to light sources, so that gas-phase pollutants can be removed under visible light irradiation through photocatalysis of light-transmitting concrete. It also has good mechanical properties, decorativeness, and functional practicability due to coated optical fibers.

A visible-light-photocatalyzed composite light-transmitting concrete contains several bundles of optical fibers, the optical fibers are coated with a protective layer on their outer surface, the protective layer contains a visible light photocatalyst, and the concrete has several gas-permeable pores. Such concrete is prepared by mixing a visible light photocatalyst and a light-transmitting glue, applying the mixture to the surface of optical fibers to form a protective layer, and using optical fibers in the concrete. The resulting concrete has dual properties of light transmittance and photocatalytic oxidation of gas-phase pollutants under visible light irradiation. The visible-light-photocatalyzed composite light-transmitting concrete significantly breaks through the limitation of photocatalytic concrete to light sources, so that gas-phase pollutants can be removed under visible light irradiation through photocatalysis of light-transmitting concrete. It also has good mechanical properties, decorativeness, and functional practicability due to coated optical fibers.