The present invention relates to a novel process for the preparation of a nitrogen containing biopolymer-based catalyst and to the novel nitrogen containing biopolymer-based catalysts obtainable by this process. In particular, the invention relates to a novel nitrogen containing biopolymer-based catalyst comprising metal particles and at least one nitrogen containing carbon layer. The invention also relates to the use of a nitrogen containing biopolymer-based catalyst in a hydrogenation process, preferably in a process for hydrogenation of nitroarenes, nitriles or imines; in a reductive dehalogenation process of C—X bonds, wherein X is Cl, Br or I, preferably in a process for dehalogenation of organohalides or in a process for deuterium labelling of arenes via dehalogenation of organohalides; or in an oxidation process. Further, the invention relates to a metal complex with the nitrogen containing biopolymer, wherein the metal is a transition metal selected from the group consisting of manganese, ruthenium, cobalt, rhodium, nickel, palladium and platinum, and wherein the nitrogen containing biopolymer is selected from chitosan, chitin and a polyamino acid.

The present disclosure relates to a multi-sandwich composite catalyst and a preparation method and application thereof. The present disclosure provides a preparation method of a multi-sandwich composite catalyst, comprises the following steps: sequentially depositing a first layer oxide, a first active metal, an oxide interlayer, a second active metal and a surface oxide on a template, and sequentially performing calcination and reduction, thereby obtaining a multi-sandwich composite catalyst; wherein the first active metal and the second active metal are different kinds of active metals. In the present disclosure, a multi-sandwich structure is formed by depositing the oxides and active metals alternately, so that the position and spacing distance of the active centers can be precisely controlled. The multi-sandwich composite catalyst prepared by the method provided described herein has a higher conversion than that of a catalyst without an interlayer when used for the catalytic reaction.

The present disclosure relates to a multi-sandwich composite catalyst and a preparation method and application thereof. The present disclosure provides a preparation method of a multi-sandwich composite catalyst, comprises the following steps: sequentially depositing a first layer oxide, a first active metal, an oxide interlayer, a second active metal and a surface oxide on a template, and sequentially performing calcination and reduction, thereby obtaining a multi-sandwich composite catalyst; wherein the first active metal and the second active metal are different kinds of active metals. In the present disclosure, a multi-sandwich structure is formed by depositing the oxides and active metals alternately, so that the position and spacing distance of the active centers can be precisely controlled. The multi-sandwich composite catalyst prepared by the method provided described herein has a higher conversion than that of a catalyst without an interlayer when used for the catalytic reaction.

The present invention relates to a process for the preparation of an aromatic amine by hydrogenation of an aromatic nitro compound, comprising the following steps: (I) providing a copper tetramine salt-based impregnation catalyst, in particular an impregnation catalyst obtainable by the incipient wetness method, comprising a metal or metal oxide on a support as a hydrogenation catalyst. At least metallic or oxidic copper (in particular CuO) is present and the mole fraction of Cu based on all metals present is in the range of 075 to 1, and wherein the support comprises shaped silicon-dioxide shaped bodies or silicon-carbide shaped bodies; (II) optionally, activating the hydrogenation catalyst by treating with hydrogen in the absence of the aromatic nitro compound; and (III) reacting the aromatic nitro compound with hydrogen in the presence of the, optionally activated, hydrogenation catalyst to obtain the aromatic amine.

The present invention relates to a process for the preparation of an aromatic amine by hydrogenation of an aromatic nitro compound, comprising the following steps: (I) providing a copper tetramine salt-based impregnation catalyst, in particular an impregnation catalyst obtainable by the incipient wetness method, comprising a metal or metal oxide on a support as a hydrogenation catalyst. At least metallic or oxidic copper (in particular CuO) is present and the mole fraction of Cu based on all metals present is in the range of 075 to 1, and wherein the support comprises shaped silicon-dioxide shaped bodies or silicon-carbide shaped bodies; (II) optionally, activating the hydrogenation catalyst by treating with hydrogen in the absence of the aromatic nitro compound; and (III) reacting the aromatic nitro compound with hydrogen in the presence of the, optionally activated, hydrogenation catalyst to obtain the aromatic amine.

A novel promotor which contains an aniline derivative is introduced. By using the promotor alone, the time and temperature of the curing reaction of the vinyl ester resin can be controlled by the unique steric effect and electronic properties of the aniline derivative. A method for preparing the above promotor is also introduced.

A novel promotor which contains an aniline derivative is introduced. By using the promotor alone, the time and temperature of the curing reaction of the vinyl ester resin can be controlled by the unique steric effect and electronic properties of the aniline derivative. A method for preparing the above promotor is also introduced.

A method of preparing a 2,6 disubstituted anilines includes, reacting a 2-amino isophthalic acid diester with sufficient Grignard reagent R.sub.2CH.sub.2MgX to form the corresponding diol product, dehydrating the diol product to the corresponding dialkene; and hydrogenating the diol product to form the corresponding aniline. The 2,6 disubstituted anilines can be used to produce N-Heterocyclic Carbenes (NHCs). The NHCs can find application in various fields such as organic synthesis, catalysis and macromolecular chemistry. Palladium catalysts containing the NHCs are also described.

A method of preparing a 2,6 disubstituted anilines includes, reacting a 2-amino isophthalic acid diester with sufficient Grignard reagent R.sub.2CH.sub.2MgX to form the corresponding diol product, dehydrating the diol product to the corresponding dialkene; and hydrogenating the diol product to form the corresponding aniline. The 2,6 disubstituted anilines can be used to produce N-Heterocyclic Carbenes (NHCs). The NHCs can find application in various fields such as organic synthesis, catalysis and macromolecular chemistry. Palladium catalysts containing the NHCs are also described.

A gas replacement process and a gas replacement apparatus are employed, in the nitro compound hydrogenation reaction process. The gas replacement process at least includes a first step of subjecting a stream to be replaced to the gas replacement in presence of a first replacement gas, and then a second step of subjecting to the gas replacement in presence of the second replacement gas. Assuming the superficial velocity of the first replacement gas is V1, and the superficial velocity of the second replacement gas is V2, then V2/V1≥1.5.