山梨坦辛酸酯的合成工艺

Synthesis process of sorbitan caprylate

采用工业级山梨醇为原料,一水合亚磷酸钠与亚磷酸为反应催化剂进行脱水实验;采用所制1,4–失水山梨醇与辛酸为原料,氧化锌为催化剂进行酯化反应;最后加入过氧化氢,进行脱色反应。考察了反应条件、催化剂选择对反应体系的影响,并按照最佳反应工艺条件制备山梨坦辛酸酯,通过高效液相色谱、红外光谱进行了表征。结果表明,以氧化锌为酯化催化剂,酯化温度为230℃,得到的失水山梨醇颜色较浅,单酯含量较高。山梨坦辛酸酯单酯的质量分数为65.73%,酸值为4.68 mg/g。自制山梨坦辛酸酯的指标在色泽及单酯含量上要优于市场产品的,可作为防腐协同增效添加剂使用。

The dehydration experiment was carried out using industrial grade sorbitol as raw material,and sodium phosphite monohydrate and phosphorous acid as reaction catalysts.The esterification reaction was carried out using the prepared 1,4-dehydration sorbitan and caprylic acid as raw materials,and zinc oxide as catalyst.Finally,the discolorization reaction was carried out by addition of hydrogen peroxide.The influence of reaction conditions and catalyst selection on the reaction system was investigated,and the sorbitan caprylate was prepared according to the optimal reaction process conditions and characterized by high performance liquid chromatography and infrared spectrum.The results showed that when zinc oxide was used as esterification catalyst and the esterification temperature was 230℃,the obtained dehydration sorbitan had lighter color and higher monoester content.The mass fraction of sorbitan caprylate monoester was 65.73%,and the acid value was 4.68 mg/g.The specifications of the self-made sorbitan caprylate were superior to those of the market product in color and monoester content,and it can be used as the synergistic additivefortheanti-corrosion.