Method for the production of lignoceric acid

摘要

The invention is related to a process for production of lignoceric acid from mixtures of long-chain aliphatic alcohols that contain lignoceric alcohol, wherein the process consists in oxidizing the mixture in a biphasic catalytic system using quaternary ammonium peroxotungstophosphate as a catalyst and hydrogen peroxide as an oxidant, followed by several physical or chemical unitary steps to separate and purify the lignoceric acid.

主权项

1. A process to obtain lignoceric acid wherein the lignoceric acid is obtained from a raw material comprising at least 50% by weight of lignoceric alcohol by means of a process comprising the steps of:
a) forming a reactant mixture by contacting the raw material, quaternary ammonium peroxotunsgtophosphate and an aqueous solution of hydrogen peroxide during a time interval sufficient to form a reacted mixture comprising lignoceric acid; b) separating the reacted mixture from step (a) into an aqueous phase and an organic phase, wherein the organic phase comprises lignoceric acid; c) forming a saponifying mixture by contacting the organic phase from step (b) with an aqueous solution of one or more alkaline metal hydroxides, where the alkaline metal hydroxides can be selected from the group consisting of sodium hydroxide or potassium hydroxide, heating the mixture to a temperature of at least 90° C. and keeping said temperature during a time interval sufficient to form a saponified mixture comprising the lignocerate; d) evaporating the saponified mixture from step (c) to obtain a residue comprising the lignocerate, wherein said residue has a water content of at most 1% by weight based on the total residue weight; e) distilling the residue from step (d) at a temperature ranging from 200° C. to 400° C. and at a pressure of less than 60 mbar to obtain a distillate and a second solid residue that comprises the lignocerate; f) forming a mixture by contacting the second solid residue from step (e) with an aqueous solution comprising one or more acids selected from the group consisting of acetic acid, hydrochloric acid and sulfuric acid, heating the solid residue and the solution mixture up to a temperature between 90° C. and 150° C. and maintaining the temperature of the mixture during a time interval sufficient to form a liquid mixture; g) cooling the liquid mixture from step (f) down to at least room temperature or less, and keeping said temperature during a time interval sufficient to form a liquid phase and a solid phase, wherein the solid phase comprises lignoceric acid; and h) separating the solid phase from step (g) from the liquid phase, wherein the solid phase comprises the lignoceric acid.