工作场所空气中挥发性有机化合物被动采样器研制及应用

Development and application of the passive sampler for the determination of volatile organic compounds in workplace air

目的研制一种适用于工作场所空气中挥发性有机化合物的无泵型被动采样器。方法基于Fick扩散定律,以耐高温、均匀分布的无机多微孔渗透管为气体扩散管,管内定量填装全碳气凝胶吸附剂,制备得到PT-1型被动采样器,并对该被动采样器对正己烷、三氯乙烯、苯和丙酮等14种有机气体的采样速率、采样时间、采样精密度和采样风速等参数进行研究。结果 PT-1型被动采样器对14种有机气体的采样速率为27.51~39.63 m L/min,采样响应时间不超过20 s;在质量浓度为150 mg/m3的混合有机气体中,采样量与采样时间呈良好的线性关系,相关系数为0.977~0.999,饱和采样时间大于11 h;采样精密度为4.01%~9.85%;在0.05~0.70 m/s的风速范围内,对14种有机气体的采样速率无明显影响。结论 PT-1型被动采样器能满足工作场所空气中挥发性有机化合物的采样要求,符合工作场所空气中挥发性有机化合物的无泵型被动采样器研制要求。

Objective To design and develop a non-pumped passive sampler for collecting volatile organic compounds in the workplace air. Methods Based on the Fick＇s law of diffusion,the inorganic porous permeation tubes which were used as gas diffusion tube were shaped from inorganic material and sintered under high temperature,after filled with carbon aerogel adsorbent,the Type PT-1 passive sampler was prepared,and its properties for the determination of 14 organic chemicals such as n-hexane,trichloroethylene,benzene and acetone in the air were evaluated on sampling rate,sampling time,sampling precision and wind speed of the sampling site. Results The sampling rate of Type PT-1 passive samper ranged from 27. 51-39. 63 m L / min for the 14 organic gases; the response time of sampling was less than 20 seconds; under150 mg / m3 mixture organic gas,the sample volume had good linear correlation with the sampling time,the correlation coefficients were 0. 993-0. 999,and the sampling time was greater than 11 hours,with the sampling precision of 4. 01%-9. 85%. The wind speed had no obvious effect on the sampling efficiency within the wind speed range of 0. 05-0. 70 m / s.Conclusion The passive sampler is suitable for sampling volatile organic compounds in workplace air and it meets the sampling demand.