Abstract: A catalyst shaped body has a column body extending in a longitudinal direction. Its cross section has a central through hole, at least four first corners and a same number of first recesses. The first corners are arranged at the same angular intervals in a circumferential direction to define a first circumscribed circle of an outer contour of the catalyst shaped body, each first corner is tangent to the first circumscribed circle. The first corners and the first recesses are alternately arranged in the circumferential direction. The first corners are an outwardly convex part of a first ellipse, and the first recesses are inwardly concave arcs tangent to the two adjacent first corners, so as to avoid bite between the first corners and/or the first recesses of the catalyst shaped body and the first recesses and/or the first corners of adjacent catalyst shaped bodies.

Abstract: A polylactic acid graft copolymer, and a preparation method therefor and the use thereof are provided. The polylactic acid graft copolymer is contains a repeating structural unit of a structure as shown in formula (A), in which R1 is H or a grafting group, and at least part of the R1 in the repeating structural unit is a grafting group. The right-angle tearing strength of the polylactic acid graft copolymer is not less than 120 kN/m, and preferably 135-150 kN/m; and the elongation at break is not less than 30%, and preferably 35-45%. The grafting-modified polylactic acid copolymerization material can be green and fully biodegradable.

Abstract: Disclosed are a method and a system for continuously preparing lactide by step control. The method includes the steps of (1) reacting a lactic acid oligomer and a depolymerization catalyst in a first depolymerization reaction unit to obtain a first liquid-phase material; (2) circulating the first liquid-phase material in a second depolymerization reaction unit for reaction until the molecular weight of the liquid-phase material is higher than 6,000 to obtain a second liquid-phase material; (3) circulating the second liquid-phase material in a third depolymerization reaction unit for reaction until the molecular weight of the liquid-phase material is higher than 10,000; and (4) collecting gas-phase crude lactide from the first depolymerization reaction unit, the second depolymerization reaction unit and the third depolymerization reaction unit, and then purifying same.

Abstract: A method for preparing diphenylamine and phenothiazine from aniline includes the steps of reacting an aniline raw material; carrying out gas-liquid separation on an obtained reaction mixture containing diphenylamine, and obtaining a first liquid product and a first gas product, separating the first liquid product, and obtaining an aniline reclaimed material and a diphenylamine product; reacting part of the obtained diphenylamine product; carrying out gas-liquid separation on an obtained reaction mixture containing phenothiazine, obtaining a second liquid product and a second gas product, and separating a phenothiazine product from the second liquid product. Coupling a diphenylamine synthesis process and a phenothiazine synthesis process reduces the energy consumption of the coupled processes. In addition, the output of the two products and purities thereof can be flexibly adjusted to optimize the product structure.

Abstract: A process for preparing succinic anhydride by hydrogenation of maleic anhydride includes the steps of: 1) mixing a maleic anhydride solution with hydrogen to obtain a first liquid phase feed; 2) carrying out a first hydrogenation reaction by passing the first liquid phase feed from bottom to top through fixed bed layer(s) of a first maleic anhydride hydrogenation catalyst arranged in a first reaction unit under first hydrogenation reaction conditions to obtain a first reaction effluent containing succinic anhydride; 3) mixing the first reaction effluent from the first reaction unit with make-up hydrogen to obtain a second liquid phase feed; and 4) carrying out a second hydrogenation reaction by passing the second liquid phase feed from bottom to top through fixed bed layer(s) of a second maleic anhydride hydrogenation catalyst arranged in a second reaction unit under second hydrogenation reaction conditions to obtain a second reaction effluent containing succinic anhydride.

Abstract: The present invention relates to the field of fine chemical industry. Specifically disclosed are a method for synthesizing 2-methylpyridine from aniline, and a method for selectively and continuously producing 2-methylpyridine and diphenylamine from aniline. The method comprises: in a hydrogen-containing atmosphere, enabling aniline and a catalyst to undergo a contact reaction at a temperature of 100-400° C., wherein the catalyst is ? zeolite carrying a metal component, and the metal component comprises an active metal component selected from at least one of W, Mo, Ni, and Co; controlling the temperature of the contact reaction to be 100-240° C. to obtain a product mainly consisting of 2-methylpyridine; and controlling the temperature of the contact reaction to be 260-400° C. to obtain a product mainly consisting of diphenylamine.

Abstract: A low sulfur diesel blockage inhibitor as shown in formula (I), a preparation method therefor, and use thereof are provided. In formula (I), x and y are each an integer between 0 and 4; m and n are each selected from H, a C1-C6 linear or branched alkyl group, or a C3-C6 cycloalkyl group. By using a vegetable oil as a raw material, a modified vegetable oil fatty acid is first obtained, and then a polar group of an unsaturated dialdehyde with a certain chain length is introduced into a molecular chain of the modified vegetable oil fatty acid.

Abstract: The present disclosure provides a microchannel liquid-liquid mixing device, comprising a microchannel component and a shell, wherein the microchannel component is fixed inside the shell, wherein an inlet is provided at one end of the shell for feeding at least two reaction liquid phases, and an outlet is provided at the other end for discharging a mixed material; said microchannel component comprises multiple stacked sheets and oleophilic fiber filaments and hydrophilic fiber filaments filled in the crevices between adjacent sheets, wherein the fiber filaments form several microchannels between them, and the fiber filaments are clamped and fixed by the sheets. The microchannel liquid-liquid mixing device is used for at least two reaction liquid phases to form a mixed material, and the at least two reaction liquid phases are cut by fiber filaments and mixed in the microchannel mixing device to form a mixed material.

Abstract: A low sulfur diesel blockage inhibitor as shown in formula (I), a preparation method therefor, and use thereof are provided. In formula (I), x and y are each an integer between 0 and 4; m and n are each selected from H, a C1-C6 linear or branched alkyl group, or a C3-C6 cycloalkyl group. By using a vegetable oil as a raw material, a modified vegetable oil fatty acid is first obtained, and then a polar group of an unsaturated dialdehyde with a certain chain length is introduced into a molecular chain of the modified vegetable oil fatty acid.