二甲苯、丙酮、三氯甲烷不同温度时间解吸效率研究

STUDY ON THE DESORPTIVE EFFICIENCY OF XYLENE,ACETONE AND CHLOROMETHANE AT DIFFERENT TEMPERATURES AND TIME INTERVALS.

目的:探讨二甲苯、丙酮、三氯甲烷在不同温度时间条件下的解吸效率.方法:用FID气相色谱CS2解吸法测定活性炭管中二甲苯、丙酮、三氯甲烷浓度.结果:30 min10～20℃或≥37℃二甲苯、丙酮、三氯甲烷解吸效率分别为83.21%～92.72%,28℃时二甲苯、丙酮、三氯甲烷解吸效率分别为87.56%～96.78%;60 min 10～20℃或≥37℃解吸效率在84.08%～96.66%,28℃解吸效率均＞98.48%;90 min 10～20℃或≥37℃解吸效率在87.04%～104.23%,28℃解吸效率均＞100%;不同时间解吸效率差异有统计学意义(P＜0.01);不同温度P＜0.05.结论:用CS2解吸附法测定上述物质时应注意环境温度及时间对解吸效率的影响,28℃应放置30min后再测定解吸效率可达到要求.

Objective： To explore the influence of the ambient temperature and time intervals on the desorpfive efficiency of xylene, acetone and chloromethane.Methods： The concentrations of xylene, acetone and chloromethane absorbed in active carbon tubes were measured by employing FID gas - chromatography with CS2 as the desorptive agent. Results： The desorptive efficiency of xylene, acetone and chloromethane at 10- 20℃ or ≥37℃ for 30 min attained 83.21 -92.72 % respectively where at 28℃ 87.64 %, 95.64 %, 96.78 % respectively . The desorptive efficiency attained 84.08 - 96.66 % at 10 - 20℃ or ≥37℃for 60min respectively, where at 28℃ of all chemical attained 〉98.48%. At 10 - 20℃or ≥37℃ for 90 min the values attained 87.04 - 104.23% and 〉 100% respectively, the difference between time intervals were significant （P 〈 0.01）, and so did the difference between ambient temperatures （ P 〈 0.05）. Conclusion. The aimbient temperature and time interval should be taken in to consideration as influencing factors in the measurement of the above chemicals when CS2 is used as the desorptive agent. The desorption should be maintained at 28℃ for 30 min to fulfill the requirement of high desorptive efficiency.