混合醇对生物油稳定性影响的研究

EFFECT OF MIXED ALCOHOL ON STABILITY OF BIO-OIL

将甲醇、乙醇分别与辛醇混合，按不同比例添加至稻壳生物油中，25℃储存6周，研究加入混合醇后生物油的水分、粘度等随时间的变化，探讨混合醇对生物油稳定性的影响，并与加入单一甲醇或乙醇的生物油进行对比。结果表明：混合醇对减缓生物油水分增长的效果优于单一醇，加入混合醇后，生物油的水分增长率分别为4．85％、4．79％，低于添加单一甲醇或乙醇时的水分增长率（分别为7．66％、7．76％）；同时，添加混合醇生物油运动粘度的增长率在4．80％～5．30％之间，低于添加单一醇生物油的6．80％。7．25％。生物油储存（6周）前后的GC-MS分析表明：生物油在加入醇类添加剂后，含量较多的醛酮类物质和羧酸类物质和醇反应，从而抑制了其参与的缩合缩聚反应，同时辛醇对生物油的均相作用减缓了大分子物质的生成，从而提升了生物油的稳定性。

The methanol and ethanol were mixed with n-octyl alcohol, respectively. Then the mixed alcohols were added to bio-oils from rice hulls in different mass fraction, which were stored at 25 ℃ for six weeks. The moisture and viscosity of bio-oils with mixed alcohols were measured in every week to show the influence of additives on the stability of bio-oil. The results indicate that mixed additives can decrease the increases of the water content of bio-oil much more than single alcohol, the increases of the water with mixed alcohols are 4.85% ＂and 4.79%, compared to the values of 7.66% and 7.76% with pure methanol and ethanol, respectively. Meanwhile, the growth of viscosity of bio-oil with mixed alcohols are between 4.80%-5.30%, which is less than 6.80%~7.25% with methanol or ethanol only. And all the bio-oil samples before and after storage were analyzed by GC-MS. The results show that some chemical compositions of bio-oil react with added alcohols, especially aldehydes and carboxylic acids, n-octyl alcohol makes the bio-oil homogeneous at the same time, which can restrain the zeneration of macromoleculars, increase stability of bio-oil.