卡尔费休方法测定生物油含水量的试验研究

An experimental study on determination of the water content in bio-oil by Karl-Fischer titration

采用卡尔费休方法,在先进的758KFD扩展型容量法自动卡氏水分测定仪上测定了生物油的含水量。研究了不同滴定溶剂、生物油进样量对生物油含水量测定结果的影响,并对已测定含水量的生物油样品进行加水试验,以考查测试结果的准确性。结果表明,在本试验条件下,采用甲醇或三氯甲烷与甲醇的混合液(3∶1)作为滴定溶剂时,生物油含水量平均值分别为36.66%和36.16%,测定结果并无太大差别,综合考虑,选用甲醇为好;采用不同生物油进样量时,测得的生物油含水量基本一样,相比而言,生物油进样量为0.06g时,其含水量的测定结果较稳定,其值为42.63%;加水试验生物油含水量测定值比计算值要高。

Karl-Fisher titration was used to Determinate the water content of bio-oil in a 758KFD Karl-Fisher titration. Effects of different solutions and bio-oil sample amount on water content in bio-oil were conducted. In addition, water adding in bio-oil sample experiments were conducted to test the accuracy and stability of the method. From the results, it can be seen that the water content in bio-oil has less changes,which were 36.86wt% and 36.16wt% respectively, when methanol or the solution of the mixture of chloroform and methanol(3∶1) were used. Methanol can be selected as test solution. The sample amount has no more influence on water content in bio-oil. When sample amount of bio-oil was 0.06 g, the water content was stable, averaging 42.63wt%. The measuring water content in bio-oil is a little higher than that of calculation result drived from water adding in bio-oil sample experiments.