102 results about "Potassium methoxide" patented technology

The invention discloses a solid basic catalyst, a preparation method of the solid basic catalyst and an application of the solid basic catalyst in ester exchange reaction. The solid basic catalyst catalyzes the ester exchange reaction by the reaction of metal organic compound and hydroxyl on a carrier under the moderate conditions to synthesize dimethyl carbonate. The solid basic catalyst provided by the invention consists of metal organic alkali and the carrier. The metal organic alkali is linked to the carrier in bond-forming manner; the metal organic alkali is one or more of lithium methoxide, lithium ethoxide, lithium isopropoxide, lithium n-butoxide, lithium tert-butoxide, sodium methoxide, sodium ethoxide, sodium isopropoxide, sodium n-butoxide, sodium tert-butoxide, potassium methoxide, potassium ethoxide, potassium isopropoxide, potassium n-butoxide and potassium tert-butoxide; the carrier is one or more of silicon oxide, aluminium oxide, titanium oxide, zirconia, mesoporous silicon oxide synthesized by the template method, mesoporous aluminium oxide synthesized by the template method, mesoporous titanium oxide synthesized by the template method, and mesoporous zirconia synthesized by the template method.

A method of preparing a bis(thio-hydrazide amide) disalt includes the steps of combining a neutral bis(thio-hydrazide amide), an organic solvent and a base to form a bis(thio-hydrazide amide) solution; and combining the solution and methyl tert-butyl ether, thereby precipitating a disalt of the bis(thio-hydrazide amide).In some embodiments, a method of preparing a bis(thio-hydrazide amide) disalt includes the steps of combining a neutral bis(thio-hydrazide amide) and an organic solvent selected from methanol, ethanol, acetone, and methyl ethyl ketone to make a mixture; adding at least two equivalents of a base selected from sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide and potassium ethoxide to the mixture, thereby forming a solution; and combining the solution and methyl tert-butyl ether to precipitate the disalt of the bis(thio-hydrazide amide).The disclosed methods do not require lyophilization and the solvents used in the process can be more readily removed to low levels consistent with pharmaceutically acceptable preparation.

The invention relates to a method for producing propylene glycol mono-methyl ether with energy conservation, which comprises the following steps: mixing propylene epoxide, methanol and a catalyst (sodium methoxide or potassium methoxide) in a preset ratio in a static mixer; preheating to a set temperature with vapor generated by absorbing reaction heat in a preheater; heating with foreign vapor with the temperature higher than 160DEG C in a heater for pre-reaction; continuously reacting materials in a tube pass of a pressureproof tube type heat exchanger; vaporizing hot water in a shell pass with surplus heat released in the reaction; and performing the subsequent routine refining process of separation and purification on materials on the outlet of the tube pass of the tube type heat exchanger to produce the propylene glycol mono-methyl ether. The method can timely remove heat released in etherification, the heat is converted to a heat source for preheating the raw materials, and the method can produce the propylene glycol mono-methyl ether with energy conservation. The heat exchange makes the temperature rise in the reaction controlled in a narrow range, so the selectivity of generated 1-methoxy-2-propanol can be improved and the quality of the product is improved.

The invention discloses a preparation method of hemicellulose-based polyether polyol. The preparation method comprises the following steps: enabling hemicellulose and glycerol to be subjected to ring-opening polymerization reaction with propylene oxide under the action of a solvent and a catalyst and under the conditions that the temperature is 90 DEG C to 150 DEG C and the pressure is less than 0.6MPa, so as to prepare the hemicellulose-based polyether polyol. The solvent is selected from dimethylformamide, toluene and dioxane; the catalyst is selected from potassium hydroxide, potassium methoxide, potassium hydroxide and sodium methoxide; the mass ratio of raw materials is that the ratio of m(propylene oxide) to m(hemicellulose) to m(glycerol) is (5 to 10) : 2 : (0 to 1); the mass dosage of the solvent is 3 to 8 times that of the hemicellulose and the dosage of the catalyst is 2 percent to 8 percent of the mass of the hemicellulose. According to the method disclosed by the invention, the polyhydroxy hemicellulose recycled from viscose fiber wastewater is used as the raw material for preparing the hemicellulose-based polyether polyol and the hemicellulose-based polyether polyol can be used for preparing rigid polyurethane foam, so that waste resources can be effectively and reasonably utilized and the environment pressure is alleviated; the utilization rate of the waste resources is high and the cost is low, so that the practicability is very good.

The invention provides a method for chemically synthesizing 10-methoxy-5H-dibenzo[b, f]azepin. The method comprises the following steps: using 10, 11-dibromo-imino-dibenzyl as a raw material to react with potassium hydroxide or potassium methoxide in methanol so to generate the10-methoxy-5H-dibenzo[b, f]azepin; preferably, firstly, adding the potassium hydroxide or the potassium methoxide in the methanol, adding the 10, 11-dibromo-imino-dibenzyl into the mixture after heating up and refluxing the mixture, and reducing the pressure and distilling the methanol after heating up and refluxing the mixture as well as keeping the temperature for a period of time; secondly, adding water into the mixture, and stirring, filtering and drying the mixture to obtain a crude product of the 10-methoxy-5H-dibenzo[b, f]azepin; and finally, adding solvent into the crude product for refinement to obtain the refined product of the 10-methoxy-5H-dibenzo[b, f]azepin. The method has the advantages of reasonable process and high reaction yield, and suitability for large-scale industrial production.

The invention discloses a regeneration and recovery device and method of a methanol alkali metal salt catalyst in a dimethyl carbonate synthesis process by an ester exchange method. The device comprises an evaporator, an evaporator reboiler, an evaporator overhead condenser, a methanol storage tank, a reaction distillation tower, an alcohol-water separation tower, an alcohol-water separation towerkettle reboiler, an alcohol-water separation tower overhead condenser and a methanol storage tank. Through the steps of evaporation, reactive distillation and alcohol-water separation, the catalyst liquid containing methanol alkali metal salt, which can be used for synthesizing dimethyl carbonate by the ester exchange method, is obtained. The process provided by the invention has the characteristics of mild conditions, simple process, easy operation and high yield, and can effectively save the use amount of the catalyst sodium methoxide or potassium methoxide in the dimethyl carbonate synthesis process by the ester exchange method, thereby lowering the dimethyl carbonate synthesis cost by the ester exchange method.

The invention relates to a method for preparing methyl 3-methoxypropionate. The molar ratio of raw material methanol to MA is 2.0 to 3.0:1, and sodium methoxide or potassium methoxide is used as a catalyst. 5.3~14.3%; first add the required amount of catalyst and methanol into the reactor, add the required MA into it for at least 10 hours under strong stirring, continue the reaction for 2~6 hours, and the reaction temperature is 45~60°C; the reaction is over Finally, under cooling and stirring, to the above reaction product, add concentrated sulfuric acid or 85% phosphoric acid to neutralize the catalyst in an amount of 1 / 2 or 1 / 3 of the molar amount of the catalyst, and maintain the temperature ≤ 35°C; Purified to obtain the target product. The mol ratio of this preparation method methyl alcohol and MA is 2.4-2.6: 1, and sodium methylate consumption is 10-11% (wt) of methanol amount, and reaction temperature is 54-56 ℃, and the reaction time is 14 hours, and wherein MA feed time is After 12 hours, the recovered product front fraction can be recycled, which has the advantages of high yield, simple refining and less catalyst consumption.

The invention discloses a method for preparing an arylboronic acid neopentyl glycol ester compound. A chemical formula of a catalyst mixed type nickel (II) coordination compound is Ni[P(OR1)3][(R2NCH2CH2NR2)C]X2. The mixed type nickel (II) coordination compound containing a phosphite ester and n-heterocyclic carbene can be used for high-efficiently catalyzing cross coupling reaction of a hydrochloric ether and bisdiboron with the existence of potassium methoxide so as to prepare the arylboronic acid neopentyl glycol ester compound. The invention provides the first case by adopting the mixed type nickel (II) coordination compound taking the phosphite ester and the n-heterocyclic carbene as auxiliary ligands for catalyzing the cross coupling reaction.

The invention discloses a method for preparing erucic acid sucrose ester, and the method comprises the following steps: a. erucic acid and methyl alcohol are subjected to esterification reaction by using concentrated sulfuric acid as catalyst, reflux reaction is carried out for 6-10 hours, and after the reaction is finished, the reaction solution is post-processed to obtain erucic acid methyl ester; b. the erucic acid methyl ester obtained in step a is added with erucic acid potash soap and sucrose to react for 2-6 hours while stirring in the presence of alkali catalyst at the reaction temperature of 120-150 DEG C and under the vacuum degree of minus 0.09-minus 0.1MPa, thus obtaining crude product of the erucic acid sucrose ester which is then purified to obtain the erucic acid sucrose ester; and the alkali catalyst is potassium carbonate, potassium methoxide, potassium ethoxide, sodium methoxide or potassium hydroxide. The prepared erucic acid sucrose ester has high monoester content and good emulsifying property, and the separation and purification process is simple, thus being suitable for industrial production.

A disclosed reaction tower for potassium methoxide production comprises a reaction tower body and a methanol evaporation assembly, the reaction tower body is internally provided with a first cavity and a second cavity, the first cavity is internally and rotatably connected with a plurality of rotating discs, each rotating disc is provided with a reaction tank, the reaction tank is provided with a convex block and a plurality of stirring blocks, and the convex block is provided with a plurality of stirring blocks; the plurality of stirring blocks are arranged at intervals around the axis direction of the rotating disc, the first end of each stirring block is provided with a gas inlet communicated with the first cavity, the second end of each stirring block is provided with a gas channel for methanol steam to enter the reaction tank, and a driving device and an alkali dissolving assembly are arranged in the second cavity; the alkali dissolving assembly conveys a strong alkali solution into the reaction tank, the driving device drives the rotating disc to rotate, so that the strong alkali solution in the reaction tank reacts with methanol steam and is stirred, the reaction is more sufficient, and the production rate and the product quality of potassium methoxide can be improved.