METHOD OF PRODUCING TETRAALKYLORTHOSILICATES FROM SILICA Russian patent published in 2019 - IPC C07F7/04 C07F7/06 

FIELD: technological processes.

SUBSTANCE: invention relates to methods of producing tetraalkylorthosilicates. Disclosed is a method of producing tetraalkylorthosilicates by direct synthesis from silica-containing material and an aliphatic alcohol in which a catalyst is dissolved, wherein the process is carried out in a flow-circulation reactor using a cartridge filled with a dehydrating agent to remove formed water and, as a result, providing shift of thermodynamic equilibrium towards increase of product concentration in alcohol at reactor outlet. Drying agent used is zeolite molecular sieves. Silica-containing material used is silica gel, ash from burning of rice husk, diatomite, pearlite, vermiculite, quartz sand. Catalysts are selected from a group of hydroxides of alkali metals and alkali or alkali-earth metal salts. Solvent and the reagent are any of aliphatic alcohols C1-C3: methanol, ethanol, n-propanol, isopropanol.

EFFECT: obtaining by the proposed method of tetraalkylorthosilicates from silica-containing material and aliphatic alcohols with achievement of high concentration of the product in the reaction mixture; method avoids the formation of oligomers and subsequent deposition of amorphous SiO₂ on walls of equipment, involves elimination of energy-consuming stage of reduction of silica to metal silicon and provides environmental cleanness due to absence of halogens during production.

9 cl, 3 dwg, 13 ex