11 results about "Methoxide" patented technology

The present invention relates to a process for preparing at least one alkali metal methoxide by reactive distillation in at least one reaction column. At the lower end of the reaction column(s), the respective alkali metal methoxide dissolved in methanol is withdrawn. The methanol / water mixture obtained at the top of the reaction column(s) is separated by distillation in a rectification column.The vapours obtained at the upper end of the rectification column are compressed in at least two stages and the energy of the vapours compressed in each case is advantageously transferred to bottoms and side streams of the rectification column. This allows particularly efficient use of the energy of the compressed vapours in the process according to the invention. In addition, the energy in the product stream of alkali metal methoxide which is obtained at the lower end of the reaction column(s) is advantageously transferred to the vapour streams from the rectification column, especially before these vapours are subjected to compression.The energy from the compressed vapour may additionally be used for operation of the reaction column(s) or for operation of a reaction column in which a process for transalcoholization of alkali metal alkoxides is performed.

A method for controlling a reactive distillation column for effecting a transalcoholisation reaction, comprising feeding a metal methoxide into the reactive distillation column via a side feed; feeding a reactant alcohol into a lower part of the reactive distillation column; withdrawing methanol from the top of the reactive distillation column; and withdrawing a solution of a product metal alkoxide in the reactant alcohol from the bottom of the reactive distillation column; wherein the method comprises a process control scheme selected from: Scheme A: establishing a signal S1 which is responsive to a temperature in the rectifying section disposed above the feed of the metal methoxide; and manipulating in response to the signal S1 the feed amount of the reactant alcohol; Scheme B: establishing a signal S1 which is responsive to a temperature in the rectifying section disposed above the feed of the metal methoxide; and manipulating in response to the signal S1 the heat supplied to the bottom of the reactive distillation column. The invention also relates to a method for controlling a reactive distillation column for effecting a transalcoholisation reaction, comprising feeding a metal methoxide into the reactive distillation column via a side feed; feeding a reactant alcohol into a lower part of the reactive distillation column; causing an auxiliary alcohol to be present in the reactive distillation column; and optionally replenishing the auxiliary alcohol via a side feed located above the feed of the reactant alcohol and below the top of the column; withdrawing methanol from the top of the reactive distillation column; and withdrawing a solution of a product metal alkoxide in the reactant alcohol from the bottom of the reactive distillation column; wherein the method comprises a process control scheme selected from: Scheme C: establishing a signal S2 which is responsive to a temperature at a point located between the feed of the metal methoxide and the bottom of the reactive distillation column; and manipulating in response to the signal S2 the feed amount of the reactant alcohol; Scheme D: establishing a signal S2 which is responsive to a temperature at a point located between the feed of the metal methoxide and the bottom of the reactive distillation column; and manipulating in response to the signal S2 the heat supplied to the bottom of the reactive distillation column. The methods of the invention allow for improved controlling of a reactive distillation column for effecting a transalcoholisation reaction.

The present application relates to the technical field of biodiesel preparation, and particularly relates to an integrated heat and power comprehensive biodiesel preparation system, which comprises a solar drying system, a zeolite activation system, a catalyst preparation system and a biodiesel preparation system. The solar drying system is used for cleaning eggshells, drying the cleaned eggshells and conveying the eggshells to the catalyst preparation system. The zeolite activation system is used for activating zeolite, improving the adsorption performance and ion exchange performance of the zeolite, recycling waste heat and conveying the activated zeolite to the catalyst preparation system. The catalyst preparation system is used for preparing calcium methoxide solid base catalyst. The solar drying system and the zeolite activation system are connected to the catalyst preparation system. The biodiesel preparation system is used for preparing biodiesel. The catalyst preparation system and the biodiesel preparation system are connected. The catalyst is prepared by using waste eggshells and methanol. Two wastes are recycled and utilized. High-temperature calcination and soaking are combined, so that the activation process of the zeolite is sufficient and thorough.

The present invention relates to an integrated method for simultaneously preparing at least two mixtures comprising alkali metal methoxides and methanol in at least two parallel reactive distillation columns, wherein a methanol feed stream is provided using a rectification column, which is subsequently used as a methanol source for the reactive distillation column, and wherein the overhead feed stream of the reactive distillation column is used as a methanol source for the rectification column.

The invention discloses a preparation method of 2 '-methoxy cytidine, and belongs to the technical field of synthesis of medical intermediates. Cytidine 1 is used as a raw material and forms a ring with sulfonyl chloride in an organic solvent to obtain an intermediate 2; reacting the intermediate 2 in an organic solvent at a high temperature to obtain epoxy cytidine 3; and finally reacting the epoxy cytidine 3 with magnesium methoxide to obtain the 2 '-methoxy cytidine. The synthesis steps are mild in overall condition, high in selectivity, less in side reaction, simple in refining method and high in operation feasibility; meanwhile, raw materials are cheap and easy to obtain, and the method is more suitable for industrial production compared with an existing route and has obvious cost advantages.

The application discloses a toughened CPVC power cable protection pipe and a preparation method thereof, and relates to the technical field of polymer materials.The application comprises the following components in terms of weight parts: functionalized cage silsesquioxane 40-42 parts; composite modified magnesium hydroxide 80-85 parts; double-shell modifier 28-30 parts; stannic methoxide 30-31 parts; calcium stearate 3-3.5 parts; stearic acid 2-2.5 parts; antioxidant 2-3 parts; rutile titanium dioxide 15-16 parts; chlorinated polyethylene 55-60 parts; polyethylene wax 4-5 parts; ultraviolet absorber 1-1.5 parts; and chlorinated polyvinyl chloride 780-800 parts.The introduction of the functionalized cage silsesquioxane, the composite modified magnesium hydroxide, the double-shell modifier, the stannic methoxide and other raw materials effectively improves the flame-retardant capacity, the smoke suppression, the impact resistance at low temperature, the aging resistance and the heat resistance of the CPVC power cable protection pipe.

Provided is a process for depolymerization of a poly(C2-C4 alkylene terephthalate), which comprises contacting a poly(C2-C4 alkylene terephthalate) with methanol and a catalyst chosen from potassium carbonate, sodium carbonate, magnesium methoxide, 1,8-diazabicyclo[5.4.0]undec-7-ene, and triazabicyclodecene, at a temperature sufficient to effect said depolymerization. The process of the invention can be carried out a substantially lower temperature and requires less methanol than necessary for zinc acetate-catalyzed reactions, and is sufficiently robust to tolerate lower-quality poly(C2-C4 alkylene terephthalate) scrap feeds.

A method for production of at least one sphingolipid of formula (1), or a composition thereof. The method comprising reacting at least one lysosphingolipid of formula (2), or a salt thereof: with a compound of formula (3): wherein W, R1, R2, R3, and R4 are as defined as for the sphingolipid of formula (1), and wherein, said reacting is performed in the presence of a base of formula (4): wherein n is 1, 2, or 3; m is 1 or 2; X is selected from Na+, K+, NH4 +, Mg2+, or Ca2+; Y is selected from OH-, CO3 2-, HCO3 -, PO4 3-, methoxide, acetate, citrate, or succinate.

The application provides a preparation method and application of 3-methoxy-4-chlorobenzaldehyde, and the preparation method comprises the following steps: (1) mixing and reacting p-chlorobenzaldehyde with a bromination reagent and an additive to obtain 3-bromo-4-chlorobenzaldehyde; (2) mixing and reacting the 3-bromo-4-chlorobenzaldehyde with a methoxide and a catalyst to obtain the 3-methoxy-4-chlorobenzaldehyde. The preparation method provided by the application starts from inexpensive p-chlorobenzaldehyde as a raw material, compared with the existing process, the reaction material is inexpensive and easy to obtain, the reaction yield is high, and the reaction condition is gentle.

The present invention relates to a process for producing at least one alkali metal methoxide by reactive distillation in at least one reaction column. At the lower end of the reaction column(s), the respective alkali metal methoxide dissolved in methanol is withdrawn. The methanol / water mixture obtained at the top of the reaction column(s) is separated by distillation in a rectification column. The energy from the vapour obtained at the top of the rectification column is transferred to a liquid or gaseous heat transfer medium, and the gaseous heat transfer medium obtained as a result is compressed in at least two stages. The energy from the respectively compressed heat transfer medium is advantageously transferred to the bottom stream and sidestream from the rectification column. This enables particularly energy-efficient use of the energy from the vapour in the process of the invention. The energy from the compressed heat transfer medium may additionally be used for operation of the reaction column(s) or for operation of a reaction column in which a process for transalcoholization of alkali metal alkoxides is conducted.

The present invention relates to a novel and efficient process for the production of 2-methoxymalonate of formula (I) by reacting malonate of formula (II) with a methoxide of formula (III) under specific conditions by a nucleophilic substitution reaction.