107results about "Preparation by hydroxy compound hydrogenation" patented technology

The invention discloses a preparation method of nitrogen-doped hierarchical pore carbon. The preparation method includes: using biomass as a raw material, and mixing the biomass with a composite activator; heating for calcining, mixing a calcining product with deionized water, standing for precipitation, and filtering to obtain precipitate; performing after-treatment to obtain the nitrogen-doped hierarchical pore carbon, wherein the composite activator is sodium hydrogen carbonate/nitrogen-containing compound, a mass ratio of sodium hydrogen carbonate to the nitrogen-containing compound is 0.25-4:1, the nitrogen-containing compound comprises at least one of ammonium oxalate, ammonium hydrogen carbonate, ammonium chloride and ammonium nitrate, and a mass ratio of the biomass to the composite activator is 1:2-16. The composite activator is utilized to activate the biomass to obtain a functionalized nitrogen-doped hierarchical pore carbon material, the preparation method is simple and easy to operate, the biomass existing in nature can be utilized directly, the obtained carbon material has rich hierarchical pore structure and can be used as a catalyst carrier to prepare high-performance nano catalysts, and utilization value of the biomass is increased greatly.

The present invention relates to novel Ruthenium catalysts and related borohydride complexes, and the use of such catalysts, inter alia, for (1) hydrogenation of amides (including polyamides) to alcohols and amines; (2) preparing amides from alcohols with amines (including the preparation of polyamides (e.g., polypeptides) by reacting dialcohols and diamines and/or by polymerization of amino alcohols); (3) hydrogenation of esters to alcohols (including hydrogenation of cyclic esters (lactones) or cyclic di-esters (di-lactones) or polyesters); (4) hydrogenation of organic carbonates (including polycarbonates) to alcohols and hydrogenation of carbamates (including polycarbamates) or urea derivatives to alcohols and amines; (5) dehydrogenative coupling of alcohols to esters; (6) hydrogenation of secondary alcohols to ketones; (7) amidation of esters (i.e., synthesis of amides from esters and amines); (8) acylation of alcohols using esters; (9) coupling of alcohols with water to form carboxylic acids; and (10) dehydrogenation of beta-amino alcohols to form pyrazines. The present invention further relates to the novel uses of certain pyridine Ruthenium catalysts.

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

A method for hydrogenating optionally substituted phenols with one hydroxyl group to cyclohexanones over modified, palladium-comprising supported catalysts. This is possible surprisingly in selected alcoholic solvents with high selectivity. Here it is even possible to recycle the catalysts employed, which hitherto has only been possible with considerable loss of selectivity.

The invention relates to a preparation method of a phenol hydrogenation catalyst, belonging to the technical field of catalysis. The catalyst uses dicyanodiamide-modified ZIF-67 as a precursor, ZIF-67 is calcined through a slow temperature programming method so as to produce a Co-CN material, then Co is removed through an acid pickling method so as to obtain a carbon-nitrogen (CN) carrier, and the carrier is stirred and soaked in a palladium chloride water solution and then is reduced in the H<2> atmosphere so as to prepare the catalyst. The preparation method has the advantages that dicyanodiamide is added in synthesis of ZIF-67 so as to improve the specific surface area of the carrier CN material, prohibit oxidization of zerovalent palladium, and acquire more zerovalent palladium; and the prepared Pd@CN catalyst presents excellent catalysis performance in reaction of hydrogenation of phenol to cyclohexanone.

The invention discloses a preparation method of a nitrogen-doped carbon catalyst and an application of the nitrogen-doped carbon catalyst in bio-oil hydrogenation. The preparation method of the nitrogen-doped carbon catalyst loaded with the active metal comprises the following steps: crushing and drying biomass waste, uniformly mixing the waste powder, an eco-friendly activating agent and urea, carrying out a pyrolysis activation nitrogen doping reaction process in an inert atmosphere to a nitrogen-doped carbon material with a developed pore structure and rich active functional groups under the synergistic effect of the biomass, the eco-friendly activating agent and the urea, and respectively capturing and anchoring active metals by utilizing developed pores and active nitrogen-containingfunctional groups of the nitrogen-doped carbon so that a stable coordination bond is formed and the highly-dispersed active metal-loaded nitrogen-doped carbon catalyst is obtained. The catalyst is applied to the catalytic hydrogenation conversion process of bio-oil derivatives, so that cyclohexanone with high selectivity can be obtained and the high-value nitrogen-doped carbon catalyst and high-efficiency and high-quality catalytic hydrogenation conversion of bio-oil can be simply and efficiently prepared from biomass.

The invention provides a method for preparing 1,3-cyclohexanedione. The method comprises the following steps: carrying out catalytic hydrogenation on resorcinol, an aqueous sodium hydroxide solution and hydrogen at a reaction temperature of 60-100 DEG C under a pressure of 3-5 MPa in the presence of a Co-Pd/C catalyst to obtain a hydrogenation solution, separating and removing the solid catalyst, pickling the hydrogenation solution with hydrochloric acid, cooling and crystallizing the pickled hydrogenation solution, carrying out solid-liquid separation to obtain a solid and a liquid, drying the obtained solid to obtain a first finished product 1,3-cyclohexanedione, extracting the obtained liquid with a 2-methylfuran and dichloromethane mixed solvent, carrying out organic phase distillation to recover the mixed solvent, and drying the obtained substance to obtain a second finished product 1,3-cyclohexanedione. Catalytic hydrogenation using the Co-Pd/C catalyst and recovery of the 1,3-cyclohexanedione from a centrifugal mother liquid through using the 2-methylfuran and dichloromethane mixed solvent are carried out to improve the total yield of the 1,3-cyclohexanedione product and reduce the COD content of reaction process wastewater.

The invention relates to a technology for production of cyclohexanone by phenol hydrogenation. Pd@CN is adopted as the catalyst to prepare cyclohexanone by an intermittent operation mode. The reaction product is subjected to inorganic membrane filtration and collection, and conventional treatment, then the cyclohexanone product can be obtained, and the Pd@CN catalyst is intercepted by the membrane and left in a reaction kettle for repeated use, thus realizing organic combination of production of cyclohexanone from phenol and repeated use of catalyst, simplifying the process, and improving the production efficiency.

The invention relates to a post-treatment method of a phenol hydrogenation Pd@CN catalyst and belongs to the technical field of catalysis. The post-treatment method comprises the following steps: after carrying out phenol hydrogenation reaction, filtering to separate a Pd@CN catalyst; putting the Pd@CN catalyst into a container and adding de-ionized water; washing for a plurality of times under certain temperature and rotary speed; filtering when a solution is hot and immersing in water. By adopting the post-treatment method provided by the invention, the Pd@CN catalyst can be effectively recycled in a phenol hydrogenation process for producing cyclohexanone and the catalysis performance is stable. According to the post-treatment method, cyclic utilization of resources is realized, the cost is reduced and energy sources are saved; green production of a process of producing cyclohexanone through one-step phenol hydrogenation is facilitated.

The invention discloses a catalyst for preparing cyclohexanone by phenol hydrogenation and a preparation method thereof. The method comprises the following steps: (1) acid is quickly mixed with a Betamolecular sieve, reflux treatment is carried out, centrifugal filtering is carried out after the reaction is finished, Zr salt or Sn salt is mixed with a reaction product, and the mixture is filtered, dried and roasted to obtain an activated strong Lewis solid acid material which has at least one pore size distribution at 1-10nm and certain alkalinity; and (2) Pd salt is prepared into a solution,and the solution is added into the material to obtain the catalyst which has high specific surface area, strong L acid and high metal dispersity. The catalyst provided by the invention is low in cost, simple in preparation method and high in catalytic activity. The turnover frequency (TOF) is higher than 100h<-1>. The phenol conversion rate and the cyclohexanone selectivity can reach 99% or above. Good stability is still shown after a cyclic test. The reaction product and the catalyst are easy to separate.

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

The invention provides a method for preparing 1,3-cyclohexanedione through gas-phase hydrogenation of resorcinol. The method comprises the following steps: dissolving resorcinol in benzene, then subjecting the dissolved resorcinol to direct vaporization, and mixing the vaporized resorcinol with hydrogen; allowing a mixture obtained in the previous step to pass through a fixed-bed reactor filled with an activated carbon-supported palladium catalyst at a mass space velocity of 0.1/h to 0.7/h, and controlling a molar ratio of hydrogen to phenol to be 2/1 to 10/1, a reaction temperature to be 180-280 DEG C and a reaction pressure of 1.0-2.0 MPa; and condensing a product obtained in the previous step with a condenser so as to obtain the hydrogenation product, i.e., 1,3-cyclohexanedione. As themethod is used for preparation of 1,3-cyclohexanedione, the conversion rate of resorcinol is up to 99.9%, and the selectivity of 1,3-cyclohexanedione is up to 97.8%.

In a process for producing a mixture of cyclohexanone and cyclohexanol, a feed comprising cyclohexanone is contacted with hydrogen in the presence of a hydrogenation catalyst under hydrogenation conditions effective to convert part of the cyclohexanone in the feed into cyclohexanol and thereby produce a hydrogenation product containing cyclohexanone and cyclohexanol. A mixture of cyclohexanone and cyclohexanol is then obtained from the hydrogenation product.

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

The invention relates to the field of organic synthesis, and discloses a preparation method of 1,3-cyclohexanedione. The method comprises the following steps: 1, in the presence of water, hydrogenating resorcinol to obtain a reaction solution containing a compound represented by the following formula (1), acidifying the reaction solution to obtain an acidified solution, and crystallizing the acidified solution to obtain a 1,3-cyclohexanedione product and an acidified mother liquor; 2, in the presence of an organic solvent, enabling the acidified mother liquor to be in contact with a complexingagent to complex 1,3-cyclohexanedione with the complexing agent, and obtaining an organic phase; 3, making the organic phase obtained in the step 2 contact the reaction solution, adjusting the pH value to 7-14 so as to make the 1,3-cyclohexanedione be dissociated from the complexing agent, and obtaining a water phase; and 4, adjusting the pH value of the water phase obtained in the step 3 to 1.0-2.5, and carrying out solid-liquid separation to obtain the 1,3-cyclohexanedione product. The preparation method disclosed by the invention has the advantages of high purity and high yield of the prepared 1,3-cyclohexanedione.

The present invention provides a process for continuously preparing a mixture of cyclohexanone and cyclohexanol comprising, a) hydrogenating phenol with gaseous hydrogen, in the presence of platinum or palladium, in a hydrogenation reactor, to produce a hydrogenation product stream comprising cyclohexanone, cyclohexanol, phenol and hydrogen; b) cooling the hydrogenation product stream to a temperature such that the fraction of phenol by mass in a first gas phase is lower than the fraction of phenol by mass in a first liquid phase; c) separating the first gas phase from the first liquid phase; d) returning at least part of the first gas phase to the hydrogenation reactor; e) heating the first liquid phase; f) purifying the first liquid phase by distillation; characterized in that heat is transferred from the hydrogenation product stream in step b) to another part of the process by means of in-process heat exchange; a mixture of cyclohexanone and cyclohexanol obtained by the process; and a chemical plant suitable for continuously preparing mixture of cyclohexanone and cyclohexanol according to the process.

The invention provides a modified palladium-carbon catalyst, which comprises: a supported palladium-carbon material; and a modifier located on the surface of the supported palladium-carbon material, wherein the modifier at least comprises one selected from polyvinyl alcohol (PVA), an acrylic resin (PAA), sodium triphenylphosphine monosulfonate, polyvinylpyrrolidone (PVP) and sodium dodecyl benzenesulfonate (SDBS). The modified palladium-carbon catalyst provided by the invention is good in stability, can be applied to a method for synthesizing 1,3-cyclohexanedione multiple times, and has highselectivity.

The invention provides a preparation method of a hydrogenation catalyst. The catalyst is a Pd-La2O3/activated carbon catalyst. The preparation method comprises the following steps: A, pretreating activated carbon; B, preparing a La2O3/activated carbon composite carrier: dissolving lanthanum salt into water and/or ethanol, mixing the solution and the activated carbon subjected to acid treatment, adjusting the pH value of the formed mixed solution to be 5.5 to 8.5, putting the solution with the pH value adjusted into a microwave device, performing microwave irradiation reaction, and performing washing, solid-liquid separation, drying and calcinations on the obtained product to obtain the La2O3/activated carbon composite carrier; and C, preparing a Pd-La2O3/activated carbon catalyst: dispersing the composite catalyst into water, mixing the composite carrier dispersed into water, methanol and a chloropalladic acid solution, performing photoreduction on the obtained mixed solution under ultraviolet light, and performing solid-liquid separation and drying on the obtained product to obtain the Pd-La2O3/activated carbon catalyst. The hydrogenation catalyst provided by the invention is particularly suitable for catalysis of phenol selective hydrogenation to prepare cyclohexanone.

The present invention provides a method of preparing an optionally substituted cyclohexanone comprising contacting an optionally substituted phenol and a catalyst in a hydrogen atmosphere. High yieldand selectivity are achieved in a substantially solvent free system.

The invention relates to a method for preparing cyclohexanone by phenol hydrogenation. The method comprises the step as follows: raw material phenol makes contact with a catalyst to prepare cyclohexanone under a hydrogen reaction condition, wherein the catalyst contains 95wt%-99.9wt% of a carrier and 0.1wt%-5wt% of Pd in terms of total weight of the carrier and Pd; and the carrier contains aluminum oxide in at least two crystal forms, wherein the content of gamma-Al2O3 is 60wt%-99wt% in terms of total weight of the carrier and Pd. The method can be applied to industrial production of preparation of cyclohexanone by phenol hydrogenation.