分光光度法测定生物柴油中的磷含量  

Determination of Phosphorus in Biodiesel by Spectrophotometry

作　　者：陈斌[1] 杨赛 李蓉[1] 窦泽坤 张梦瑶 马晓迅[1] 

机构地区：[1]西北大学化工学院,陕西西安710069

出　　处：《分析科学学报》2018年第1期52-56,共5页Journal of Analytical Science

基　　金：国家自然科学基金(No.21376191);陕西省教育厅产业化培育项目(No.2013JC23);陕西省教育厅服务地方专项计划(No.14JF027);陕西省自然科学基金(No.2011JM2013)

摘　　要：本文通过对生物柴油样品进行皂化-灰化,建立了一种测定生物柴油中磷含量的分光光度分析方法。助剂KOH和K2SO4与生物柴油反应生成皂,皂灰化后得到易溶的磷酸钾盐,经钼蓝比色法测得生物柴油中的磷含量。该方法将生物柴油的催化灰化过程转化为皂的灰化过程,克服了生物柴油灰化过程的飞溅、燃烧,缩短了灰化时间,简化了后续操作。结果表明:本方法测定生物柴油中的磷含量与国家标准方法相当,相对标准偏差为3.01%,回收率在96.04%~105.61%之间,检测限为0.37mg/kg,定量限为1.22mg/kg。本方法准确度和精密度较高,可满足生物柴油中磷含量日常检测的需要。A method for the determination of phosphorus in biodiesel by spectrophotometry was established by saponification and ashing of biodiesel samples. Auxiliaries KOH and K2 SO4 reacted with biodiesel to form soap and soap ash to obtain soluble potassium phosphate. The phosphorus content of the sample was measured by molybdenum blue colorimetry. The method converts the catalytic ashing process of biodiesel into the ashing process of soap,overcomes the splashing and burning in the biodiesel ashing process, shortens the ashing time and simplifies the follow-up operation. The results showed that the phosphorus contents obtained by this method were similar to those obtained by the official method. The RSD was 3.01% and the recoveries were between 96.04% and 105.61%. The detection limit of the method was 0.37 mg/kg and the limit of quantification was 1.22 mg/kg. This method doesn＇t rely on large-scale instrument, has the advantages of low cost, high accuracy and precision, and can meet the daily detection of phosphorus in biodiesel.

关 键 词：生物柴油 灰化 钼蓝比色法 磷含量 

分 类 号：O657.3[理学—分析化学]