对气相色谱-质谱法测定水或沉积物样品中15种硝基苯类化合物(NB′s)含量时,所用的4种固相萃取(SPE)小柱(佛罗里硅土、碳胶、C18和PEP)和混合淋洗剂的配比对目标化合物的回收率和净化效果等做了比较试验。结果表明:上述4种小柱均可用作15种NB′s的净化柱;② 以二氯甲烷或正己烷为主的混合淋洗剂对PEP以外的3种SPE小柱的淋洗回收率近似,可选用二氯甲烷及二氯甲烷-正己烷(9+1)、二氯甲烷-丙酮(或乙酸乙酯)(9+1)、正己烷-丙酮(或乙酸乙酯)(9+1)等混合溶剂作淋洗剂;③ 用PEP小柱时,在无水分干扰时可选用正己烷,在有水分干扰时则可选用正己烷-丙酮(或乙酸乙酯)(9+1)混合淋洗剂,也可用正己烷-二氯甲烷(9+1)混合淋洗剂。所选用的各淋洗剂均能在10 mL淋洗体积内达到各目标化合物的要求回收率。

It the GC-MS determination of 15 nitrobenzenes (NB′s) in samples of water and sediments, a comparative study on the choice of SPE columns (among the columns of Florida florisil, silica gel, C18 and PEP) and of composition of mixed eluants was made. It was found that: ① all the 4 SPE columns were feasible for purification of the 15 NB′s; ② similar elution efficiencies and recoveries of purification on the SPE columns (besides PEP column) were obtained by using mixed eluants with dichloromethane (DCM) or with n-hexane (NHX) as the main component, hence either pure DCM or mixtures of DCM-NHX(9+1), DCM-acetone (or ethyl acetate) (9+1) and NHX-acetone (or ethyl acetate) (9+1) could be selected as eluant; ③ for use with PEP column, pure NHX could be used in the absence of interference of moisture, and mixtures of NHX-acetone (or ethyl acetate) (9+1) as well as NHX-DCM (9+1) could be used in the presence of interference of moisture. Required recovery of the 15 NB′s was attained by elution with 10 mL of each of the above mentioned eluants.