基于自燃点法的复配麻风树柴油的十六烷值改进与测定

Improvement and Determination of Cetane Number of the Biodiesel from Jatropha Oil by Self-ignition Point Method

采用自燃点法,用自制自燃点测定仪在考察标准燃料自燃点与十六烷值（CN）的线性关系成立的基础上,在复配生物柴油（即麻风树种子油经添加黏度调整剂和改进剂等复配而成）中添加硝酸正丁酯（NBN）、草酸正丁酯（DNBO）、氢过氧化叔丁烷（TBHP）以及三者两两复配的CN改进剂,实验结果表明：单一的CN改进剂添加量为0.1%~1.0%时,能有效提高复配生物柴油的CN15~25个单位;单一添加时以NBN效果最好,当其添加量为0.6%,则复配生物柴油的CN由27提高到50。复配CN改进剂,DNBO与TBHP复配有协同增效作用,当其复配比例为1∶9~9∶1,添加量为0.6%时,复配生物柴油的CN为52~54;而NBN与DNBO的复配无协同效应。在自燃点测定及其计算CN的指导下,用单缸柴油机验证CN预测及添加改进剂的效果,结果表明：自燃点测定预测燃料的十六烷值的方法是可行的。

The establishment of cetane number（CN） with simple methodology is important in direct utilization of vegetable oils as diesel fuel. By using the method of measuring self-ignition temperature on the basis of linear relation between self-ignition point and CN,the improvement and measurement of the CN of the compound biodiesel was performed by adding the CN improvers such as n-butyl nitrate （ NBN）, di-n-butyl oxalate （ DNBO）, ten-butyl hydroperoxide （ TBHP）, and both of compounds. The results showed that the CN of the compound biodiesel could be effectively increased by 15 - 25 via adding CN with the amount of O. 1% - 1.0%. n-Butyl nitrate was the most effective improver in three compounds. When the addition of NBN was 0. 6 %, the CN of compound biodiesel increased from 27 to 50. The synergistic effect was proved by compound experiment of DNBO and TBI-IP,the CN of the compound biodiesel increased to 52 - 54 by the adding amount of 0.6 % with the ratio of the proportion changing from 1 ： 9 to 9 ： 1. DNBO and NBN didn＇t have synergistic effect. Under the guidance of self-ignition point measurements and the calculative CN, the effect of improving the CN and the prediction utility of the CN were verified by the combustion situation of single cylinder diesel. It was shown that this method is feasible.