管式静态混合反应器中加入共溶剂制备生物柴油

Continuous preparation of biodiesel with co-solvent in tubular static mixer

用菜籽油毛油和甲醇为原料,KOH为催化剂在自制的管式静态混合反应器中连续化制备生物柴油,研究了加入共溶剂四氢呋喃或者丁酮时,对生物柴油产率的影响。实验发现加入共溶剂,可以明显提高生物柴油的产率。在以醇油摩尔比6︰1,催化剂KOH占油脂质量的1%,加热导热油的温度控制在250～270℃,原料通过管式反应器的流速为5L/min的条件下,原料通过管式静态混合反应器一次的产率,由未加共溶剂时的56%,提高到80%以上,最高产率则由未加共溶剂的76.5%,提高到了94.1%。在管式静态混合反应器中适当减少共溶剂的用量,生物柴油的产率变化不大。加入共溶剂,反应可以在6～9min达到90%以上的产率。

A continuous process for biodiesel preparation was investigated in a pilot plant, using rapeseed oil and methanol as the feedstock, and KOH as the catalyst. The process was equiped with a tubular static mixing reactor and co-solvent such as tetrahydrofuran（THF） and butanone was added in. The experiment showed that the yield of biodiesel was improved evidently when co-solvent was added in. Compared with no co-solvent the conversion ratio of rapeseed oil to biodiesel increased from 56 % to above 80% at feedstock passed the pipe once and the tiptop conversion ratio increased from 76.5% to 94.1% on the condition that molar ratio of methanol to oil was 6 ： 1, catalyst was 1% weight of oil, the heating temperature was controlled in 250℃ to 270℃, and total flow was 5 L/min. It＇s indicated that conversion ratio of rapeseed oil to biodiesel changed little if the dosage of co-solvent reduced properly. All these reaction could reach 90% conversion ratio at 6min to 9min with co-solvent added in.