39results about How to "Apply many times" patented technology

A catalyst for preparing dichlorophenylamine by hydrogenating dichloronitrobenzene is composed of the activated carbon as carrier and the Pd as active component (0.2-2.0 Wt%) carried by said activated carbon. Its preparing process includes such steps as cyclically immersing activated carbon in diluted nitric acid, water washing until it becomes neutral, immersing in the aqueous solution of PdCl2, filtering, and baking the filtered cake. It has high catalytic performance and long cyclic service life.

The invention discloses a catalyst as well as a preparation method and application of the catalyst. The catalyst is composed of a carrier and a composite carbon-metal quantum dot supported on the carrier; the particle size of the catalyst ranges from 100nm to 1000nm; the carrier is a mesoporous carbon microsphere; the composite carbon-metal quantum dot is not larger than 15nm and contains 10-90% of metal; the metal in the composite carbon-metal quantum dot is one or a combination of several of platinum, palladium, iridium, ruthenium and rhodium; the loads of platinum, palladium, iridium, ruthenium and rhodium are respectively 0-10.0%, 0-10.0%, 0-10.0%, 0-10.0% and 0-5.0% based on the mass of the carrier, and the loads of palladium, platinum and rhodium are not equal to zero; and the total load of the metal is 1.0-11.5%. The invention provides the application of the catalyst to reaction for synthesizing a chlorinated aromatic amine compound shown as a formula (II) by carrying out selective catalytic hydrogenation on a chlorinated aromatic nitrocompound shown as a formula (I), and the catalyst has the characteristics of high hydrogenation reaction rate, high conversion rate, high catalytic activity and high stability.

The invention discloses preparation of a sulfur-doped activated carbon catalyst loaded with noble metal and application of the sulfur-doped activated carbon catalyst loaded with the noble metal in halogenated aromatic nitro-compound hydrogenation reaction. A preparation method is carried out according to the following steps that 1, a hydrothermal method is adopted for preparing sulfur-doped activated carbon; 2, the sulfur-doped activated carbon is taken, deionized water is added to prepare slurry, under stirring, a soluble noble metal compound solution is added dropwise, the noble metal is Pdor Pt, stirring is conducted, then a sodium acetate solution is added, stirring is conducted, an alkaline solution is added dropwise to adjust a pH to be 7-9, stirring is continued, and then a formaldehyde solution is added dropwise for reduction, so that the sulfur-doped activated carbon catalyst loaded with the noble metal is obtained. The catalyst is simple in preparation method operation, lowin cost, small in generated pollution and beneficial for industrial application. The catalyst is applied to halogenated aromatic nitro-compound liquid phase catalytic hydrogenation to prepare halogenated arylamine, the conversion rate and the selectivity are high, and the catalyst is good in stability, and can be recovered and reused for multiple times.

The invention discloses a photo-thermal catalytic hydrogenation catalyst as well as preparation and application thereof to selective hydrogenation reaction of 3,4-dichloronitrobenzene. The photo-thermal catalytic hydrogenation catalyst is prepared from a mesoporous carbon microsphere carrier, and carbon quantum dots and metal quantum dots which are loaded on the surface of the carrier; the size ofthe catalyst is 50 to 100nm; the grain diameter range of the carbon quantum dots is 4.5 to 6.5nm; the metal quantum dots are one or a combination of two of palladium quantum dots and platinum quantumdots; the grain diameter range of the metal quantum dots is 10 to 15nm; in the catalyst, the mass percent of the carbon quantum dots and the metal quantum dots is 10 to 30 percent and 1 to 2 percentrespectively. The photo-thermal catalytic hydrogenation catalyst provided by the invention is applied to reaction of selectively carrying out catalytic hydrogenation on the 3,4-dichloronitrobenzene under the irradiation of ultraviolet light with the wavelength of 280 to 350nm to synthesize 3,4-dichloroaniline, and has the characteristics of high conversion rate, good selectivity, rapid hydrogenation reaction speed and good stability.

The invention provides a high-dispersion nitrogen-sulfur co-doped catalyst and a preparation method thereof, and an application in a reaction of synthesizing N,N-dibenzylidene ethylenediamine from N,N-dibenzylidene ethylenediamine. According to the invention, thiourea is adopted for one-step doping, so that operation is convenient, pollution is reduced, and defect sites generated by doping are beneficial to adsorption of precious metal; heteroatom nitrogen in a carbon skeleton can provide proper alkalinity, so that polymerization reaction of N,N-dibenzylidene ethylenediamine is reduced; heteroatomic sulfur plays a complexing role, so that strong interaction between sulfur and platinum can properly reduce the activity of the catalyst, inhibit the generation of CN hydrogenolysis reaction andimprove the selectivity of a target product; metal nanoparticles are not easy to agglomerate or lose in hydrogenation reaction, so that the service life of the catalyst is prolonged, and under the combined action of heteroatom nitrogen and heteroatom sulfur, the stability of platinum is greatly improved; and the catalyst provided by the invention has the advantages of mild use conditions, good stability, less catalyst dosage, more application times and long service life.

The invention discloses a loaded type catalyst and a preparation method and application thereof. The catalyst is prepared from a carrier and an active component loaded on the carrier; the carrier is activated carbon; the active component is prepared from palladium, lanthanum, cerium and boron; mass of the palladium, the lanthanum, the cerium and the boron respectively is 3.0 to 15.0 percent, 0.1 to 5.0 percent, 0.1 to 5.0 percent and 0.1 to 2.5 percent of mass of the carrier. The invention provides application of the loaded type catalyst to a chlorobenzene compound as shown in a formula (I) and an alcohol reaction generation as shown in a formula (II) and phenyl ether compounds as shown in a formula (III). The catalyst prepared by the preparation method has excellent catalytic performance for the chlorobenzene compound, a catalytic conversion rate can reach 100 percent, selectivity is 99 percent or above, and the catalyst has high stability, and not only can effective degradation of the chlorobenzene compound be implemented, but also phenyl ether organic matter with a higher application value can be obtained. (see the descreiption).

The invention discloses a photo-thermal catalytic hydrogenation catalyst as well as a preparation method and application thereof. The photo-thermal catalytic hydrogenation catalyst is prepared from amesoporous carbon microsphere carrier, and carbon quantum dots and metal quantum dots which are loaded on the surface of the carrier; the size of the catalyst is 50 to 100nm; the grain diameter rangeof the carbon quantum dots is 1 to 4nm; the metal quantum dots are one or a combination of two of palladium quantum dots and platinum quantum dots; the grain diameter range of the metal quantum dots is 10 to 15nm; in the catalyst, the mass percent of the carbon quantum dots and the metal quantum dots is 10 to 30 percent and 1 to 2 percent respectively. The photo-thermal catalytic hydrogenation catalyst provided by the invention is applied to reaction of selectively carrying out catalytic hydrogenation on hydroquinone under the irradiation of ultraviolet light with the wavelength of 200 to 280nm to synthesize 1,4-cyclohexanediol, and has the characteristics of high conversion rate, good selectivity and good stability.

The invention relates to the technical field of fine chemical engineering, in particular to a preparation method of ethyl p-aminobenzoate. The invention relates to a preparation method of ethyl p-aminobenzoate, which is characterized by comprising the following steps: (1) adding p-nitrobenzoic acid, ethanol and a composite catalyst into a reaction kettle; (2) carrying out a reaction for 6-8 h under a reflux condition to obtain ethyl p-aminobenzoate, an intermediate p-aminobenzoic acid and p-nitrobenzoic acid which is not completely reacted; and (3) carrying out post-treatment to obtain the ethyl p-aminobenzoate finished product. The composite catalyst is composed of sulfate, an inorganic reducing agent, a diatomite and an amine accelerator.

The invention provides a preparation method of a Schiff base and metal cobalt complex. The preparation method includes: charging, suction-filtering, heating for reflux, dropwise adding 3, 5-ditert-butyl salicylaldehyde-methanol solution, allowing heat-insulating reaction for the first time, dropwise adding cobalt acetate-methanol solution, and allowing heat-insulating reaction for the second time.The invention further provides application of the complex in preparing R-propylene glycol. A molar ratio of Schiff base to metal cobalt is 2:1, specific rotation is -1200, and yield is 91%. When thecomplex serving as a catalyst is used for preparing R-propylene glycol, content of R-propylene glycol is higher than 99.5%, moisture is lower than 0.5%, and specific rotation is minus 16.8-minus 17.0.