Menetelmä puhdistetun metanolin valmistamiseksi sulfaattisellukeiton lauhteesta

摘要

The invention relates to a method for making purified methanol from a liquefied fraction obtained from a sulfate pulp process and containing methanol and sulfur contaminants, its main sulfur contaminants being methyl mercaptan, dimethyl sulfide and dimethyl disulfide. According to the invention, the fraction is subjected to an oxidation treatment, followed by separating the methanol by distillation or water vapor distillation from distillation residue containing sulfur-bearing oxidation products. From the distillation residue can be crystallized dimethyl sulfone produced in oxidation and obtained as a by-product of the process.