Takata T, Aoki B
Sangyo Igaku. 1981 Jan;23(1):42-50. doi: 10.1539/joh1959.23.42.
For a simple analysis of organic solvent vapours in working environmental air, we investigated the following method. First, join the adsorption tube (2 ml of 60--80 mesh silica gel packed in a 5 mm phi x 18 cm glass tube) to hand vacuum pump and suck 200 ml of the sample air. After adsorption, join this adsorption tube to the sampling bottle under reduced pressure. Second, open the cock of the sampling bottle and heat only the adsorption tube in an oven for 3 min. In the operation mentioned above, organic solvent vapours desorbed from the silica gel transfer smoothly into the sampling bottle. After desorption, take 1 ml of air from the sampling bottle and determine the sample quantities with the gas chromatograph. Sample solvents used were as follows: n-hexane, cyclohexane, benzene, toluene, m-xylene, styrene, 1.1.1-trichloroethane, dichloromethane, tetrachloroethylene, ethylacetate, acetone, methyl-ethylketone, methylisobutylketone, methanol, ethanol, n-propanol, and n-butanol. We obtained the following results. (1) 60--80 mesh silica gel is appropriate for this method. (2) Heating temperature to get 100% recovery varies with the type of organic solvent. m-Xylene and styrene require 250 degrees C, methylisobutylketone and n-butanol 200 degrees C, and the others 150 degrees C. (3) If the adsorption tube is preserved in a freezer at -20 degrees C, no decrease is observed for up to 7 days. At room temperatures, however, 1.1.1-trichloroethane, dichloromethane, tetrachloroethylene, n-hexane, and cyclohexane decreased by the amount 4-10% in the tube for each 24-hour period. These sample should be preserved at lower temperatures soon after absorbing on the silica gel. This method is simple and accurate, so valid for analysis of organic solvent vapours in the working environmental air.
为了对工作环境空气中的有机溶剂蒸气进行简单分析，我们研究了以下方法。首先，将吸附管（5毫米外径×18厘米玻璃管中装填2毫升60 - 80目硅胶）连接到手真空泵上，抽吸200毫升样品空气。吸附后，在减压条件下将此吸附管连接到采样瓶上。其次，打开采样瓶的旋塞，仅在烘箱中加热吸附管3分钟。在上述操作中，从硅胶上解吸的有机溶剂蒸气顺利转移到采样瓶中。解吸后，从采样瓶中抽取1毫升空气，并用气相色谱仪测定样品量。使用的样品溶剂如下：正己烷、环己烷、苯、甲苯、间二甲苯、苯乙烯、1,1,1 - 三氯乙烷、二氯甲烷、四氯乙烯、乙酸乙酯、丙酮、甲乙酮、甲基异丁基酮、甲醇、乙醇、正丙醇和正丁醇。我们得到了以下结果。（1）60 - 80目硅胶适用于此方法。（2）获得100%回收率的加热温度随有机溶剂类型而变化。间二甲苯和苯乙烯需要250℃，甲基异丁基酮和正丁醇需要200℃，其他的需要150℃。（3）如果将吸附管保存在-20℃的冰箱中，7天内无减少现象。然而，在室温下，1,1,1 - 三氯乙烷、二氯甲烷、四氯乙烯、正己烷和环己烷在管中每24小时减少4 - 10%。这些样品在吸附到硅胶上后应尽快保存在较低温度下。此方法简单准确，因此对工作环境空气中有机溶剂蒸气的分析有效。
