气相色谱测定豆粕残溶条件的研究

Study on the Determination Conditions of Residual Solvent in Soybean Meal by Gas Chromatography

对溶剂在豆粕中的吸附和解吸达到平衡的时间进行了一系列的探索试验 ,从而得知 :待测试样在 80℃水浴中至少需要 2h才能达到平衡 ,30min的时间显然是不够的。标准试样配制需要在一个星期前进行 ,若配置后马上使用 ,会使响应值偏高 ,导致测定结果偏低。配制标准试样所用的溶剂最好预先蒸馏 ,收集 6 7℃以上的馏分。改进测定条件后的豆粕残溶测定结果具有很好的复现性。

A series of explorative experiments have been done,in order to look for the time adsorption and desorption of solvent in soybean meal reaching balances.The results indicate it needs to keep at least two hours that preparing samples in water bathing at 80℃ reach balances,30 minute is not enough obviously.In addition,the preparations of the standard samples must be completed at least before a week.If they are tested at once by instrument after making up,their response values will increase and the results will reduce.The solvent for making up standard samples had better be beforehand distilled,and gather the distillate components above 67℃.The results in new experiment conditions of determinting residual solvent in soybean meal have good repeatability.