Disclosed is a method for preparing a solid material including manganese, the method including the following steps: a. bringing into contact an aqueous effluent including manganese, for example at least 5 mg/L, typically at least 5 to 50 mg/L, and preferably 7 to 25 mg/L of manganese, with an oxidizing agent, manganese, preferably at a temperature between 10° C. and 50° C., and obtaining an oxidized aqueous solution; b. adding a base to the oxidized aqueous solution obtained at the end of step a) until a pH of between 8 and 12, preferably greater than 9, and preferably from 9 to 10.5, and obtaining a solution including a precipitate; c. filtration of the solution obtained at the end of step b); and d. obtaining a solid material including manganese, and especially manganese (IV) and/or Mn (III).

Disclosed is a method for preparing a solid material including manganese, the method including the following steps: a. bringing into contact an aqueous effluent including manganese, for example at least 5 mg/L, typically at least 5 to 50 mg/L, and preferably 7 to 25 mg/L of manganese, with an oxidizing agent, manganese, preferably at a temperature between 10° C. and 50° C., and obtaining an oxidized aqueous solution; b. adding a base to the oxidized aqueous solution obtained at the end of step a) until a pH of between 8 and 12, preferably greater than 9, and preferably from 9 to 10.5, and obtaining a solution including a precipitate; c. filtration of the solution obtained at the end of step b); and d. obtaining a solid material including manganese, and especially manganese (IV) and/or Mn (III).

Ceramic compositions with catalytic activity are provided, along with methods for using such catalytic ceramic compositions. The ceramic compositions correspond to compositions that can acquire increased catalytic activity by cyclic exposure of the ceramic composition to reducing and oxidizing environments at a sufficiently elevated temperature. The ceramic compositions can be beneficial for use as catalysts in reaction environments involving swings of temperature and/or pressure conditions, such as a reverse flow reaction environment. Based on cyclic exposure to oxidizing and reducing conditions, the surface of the ceramic composition can be converted from a substantially fully oxidized state to various states including at least some dopant metal particles supported on a structural oxide surface.

Disclosed is a mixed oxide comprising Ce.sub.aZr.sub.bM.sub.cL.sub.dO.sub.z, where: M is Y, Sc, Ca, Mg or a mixture thereof; L is one or more rare earth elements, not including Y or Sc; 0.30≤a≤0.60; 0<c≤0.3; d≤0.1; b=1−(a+c+d); and when M is trivalent, z=(2a+2b+1.5d+1.5c), or when M is divalent, z=(2a+2b+1.5d+c).

Disclosed is a mixed oxide comprising Ce.sub.aZr.sub.bM.sub.cL.sub.dO.sub.z, where: M is Y, Sc, Ca, Mg or a mixture thereof; L is one or more rare earth elements, not including Y or Sc; 0.30≤a≤0.60; 0<c≤0.3; d≤0.1; b=1−(a+c+d); and when M is trivalent, z=(2a+2b+1.5d+1.5c), or when M is divalent, z=(2a+2b+1.5d+c).

A hydrogenation catalyst includes copper oxide, an alkali metal, and an acid-stabilized silica, wherein hydrogenation catalyst has a Brunauer-Emmett-Teller (“BET”) surface area of greater than or equal to about 15 m2/g. The hydrogenation catalysts are effective for converting aldehydes, ketones, and esters to alcohols and/or diesters to diols.

Improved electrochemical production of hydrogen peroxide is provided with a surface-oxidized carbon catalyst. The carbon can be, for example, carbon black or carbon nanotubes. The oxidation of the carbon can be performed, for example, by heating the carbon in nitric acid, or by heating the carbon in a base. The resulting carbon catalyst can have a distinctive oxygen is peak in its X-ray photoelectron spectrum.

Improved electrochemical production of hydrogen peroxide is provided with a surface-oxidized carbon catalyst. The carbon can be, for example, carbon black or carbon nanotubes. The oxidation of the carbon can be performed, for example, by heating the carbon in nitric acid, or by heating the carbon in a base. The resulting carbon catalyst can have a distinctive oxygen is peak in its X-ray photoelectron spectrum.

The present invention provides an In—NH.sub.2/g-C.sub.3N.sub.4 nanocomposites with visible-light photocatalytic activity and application thereof, which can effectively remove organic pollutants (such as tetracycline) in water. First, the graphite phase carbonitride carbon (g-C.sub.3N.sub.4) was obtained by thermal condensation, and g-C.sub.3N.sub.4 nanosheet was prepared by thermal oxidative etching. Then, acicular MIL-68(In)—NH.sub.2 (In—NH.sub.2) was grown in situ on the surface of g-C.sub.3N.sub.4 nanosheet by solvothermal method. The In—NH.sub.2/g-C.sub.3N.sub.4 nanocomposites with high visible-light photocatalytic activity were obtained. The CNNS firstly was prepared in the present invention, which is beneficial to the needle-like In—NH.sub.2 growing on the surface of CNNS and having close interfacial contact with each other, forming a heterojunction, promoting the separation of photogenerated electrons and holes pairs, and enhancing visible-light photocatalytic degradation of organic pollutants. The nanocomposites show high structural stability and reusability, which has great potential in the field of water remediation.

The present invention provides an In—NH.sub.2/g-C.sub.3N.sub.4 nanocomposites with visible-light photocatalytic activity and application thereof, which can effectively remove organic pollutants (such as tetracycline) in water. First, the graphite phase carbonitride carbon (g-C.sub.3N.sub.4) was obtained by thermal condensation, and g-C.sub.3N.sub.4 nanosheet was prepared by thermal oxidative etching. Then, acicular MIL-68(In)—NH.sub.2 (In—NH.sub.2) was grown in situ on the surface of g-C.sub.3N.sub.4 nanosheet by solvothermal method. The In—NH.sub.2/g-C.sub.3N.sub.4 nanocomposites with high visible-light photocatalytic activity were obtained. The CNNS firstly was prepared in the present invention, which is beneficial to the needle-like In—NH.sub.2 growing on the surface of CNNS and having close interfacial contact with each other, forming a heterojunction, promoting the separation of photogenerated electrons and holes pairs, and enhancing visible-light photocatalytic degradation of organic pollutants. The nanocomposites show high structural stability and reusability, which has great potential in the field of water remediation.