氧化锌催化地沟油预酯化反应性能

Effect of Zinc Oxide Catalyzes Pre-esterification of Gutter Oil

地沟油是一种可再生资源,是合成生物柴油的重要前驱体,但过高的酸价往往降低其作为炼制生物柴油原材料的品质。预酯化反应能有效降低地沟油的酸价,避免其对生物柴油合成设备的腐蚀,并提高生物柴油的合成效率。探究了氢氧化钠、氢氧化钙、无水碳酸钾、氧化锌、碱式碳酸锆、HND-64固体碱6种碱性催化剂对地沟油酯化反应效果的影响,通过酸价测试发现,氧化锌催化地沟油酯化反应效果最佳,在最佳使用剂量0.4%,反应温度180℃时,氧化锌可将地沟油酸价从73.39 mgKOH/g降至8.95 mgKOH/g;同时氧化锌催化剂强化酯化反应,降低地沟油中的硫含量,使其硫含量下降23.4%。研究结果可为提高地沟油品质提供理论依据。

Gutter oil is a kind of renewable resources and an important precursor of biodiesel synthesis,but the higher acid value of gutter oil decreases its performance upon biodiesel synthesis.The pre-esterification can effectively reduce the acid value of gutter oil,avoid the corrosion of biodiesel synthesis equipment,and improve the efficiency of biodiesel synthesis.In this work,sodium hydroxide,calcium hydroxide,anhydrous potassium carbonate,zinc oxide,basic zirconium carbonate and HND-64 solid base as catalyst,were investigated to affect the esterification efficiency of gutter oil.From the result of acid value,it was found that the optimal catalyst for esterification of gutter oil was zinc oxide.When at the dosage of 0.4%and reaction temperature of 180 o C,the acid value of gutter oil decreased from 73.39 mgKOH/g to 8.95 mgKOH/g.Meanwhile,addition of ZnO catalyst was enhanced esterification reaction,reducing the sulfur content by 23.4%in gutter oil.This study provides theoretical support for improving the quality of gutter oil.