摘要
研制了活性炭涂层固相微萃取进样器。推导了萃取量与样品体积和组分浓度间的数学关系式。建立了活性炭涂层固相微萃取/热脱附法测定气体中苯的方法。提出了改变样品体积测定组分浓度和吸附常数的方法。当采样体积≤100mL时,萃取量与样品体积存在线性关系。样品浓度≤52ng.mL-1时,萃取量与浓度的线性关系为A=140.09C+16.24,相关系数0.996。实验测定萃取量倒数与样品体积倒数的线性方程为1/A=0.11805/Vg+0.00011,相关系数R2=0.999,活性炭涂层对苯的吸附常数为2.15×106。实测苯的相对标准偏差(RSD)<6.98%(n=6),相对误差7.50%,检出限是5.86×10-6ng.mL-1,线性范围104,对苯的最大吸附量2636ng,灵敏度比商品固相微萃取(PDMS)高近50倍。
A new solid phase microextraction （SPME） fiber coated with porous layer activated charcoal has been developed for the quantification of benzene in gas. There is a linear relationship between the amount of benzene extracted by the SPME coated with porous layer activated charcoal and gas volume （ Vs ） at ≤ 100 mL of gas phase volume. The linear equation is A = 25,815 Vg ＋ 36.462 with correlation coefficient （ R^2 ） of 0. 999 . The linear equation between amounts of benzene extracted by the SPME coated with porous layer activated charcoal and concentration of benzene （C） in gas phase is A = 140.09C ＋ 16.24 with correlation coefficient （ R2 ） of 0.996,ranging of concentration from 0.087 9 to 52 ng·mL^-1. The linear equation between the reciprocal of amounts of benzene extracted （ 1/A ） and the reciprocal of gas volume （ 1/Vs ） is 1/A = 0.118 05/V, ＋ 0.000 11, with correlation coefficient （R2） of 0.999 9. The extraction recovery and sorption coefficient （K）for benzene are 92.47% and 2.15 ×10^6, respectively. The relative standard deviation （RSD） and relative error （RE） are 6.98% and 7.50% for benzene, respectively. Detection limit of 5.86 × 10^-3 ng· mL^-1 and linear range of 104 are measured. The maximum amount of the adsorbed benzene is 2 636 ng. The results obtained by use of this porous layer activated charcoal fiber are also compared with results obtained by use of a polydimethylsiloxane（PDMS） coated fiber（SUPELCO, USA）.
出处
《北京大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第2期249-253,共5页
Acta Scientiarum Naturalium Universitatis Pekinensis
关键词
活性炭涂层固相微萃取
热脱附
苯
室内空气
solid phase microextraction
thermal desorption
benzene
indoor air
