Study on the solid sorbent tube for capturing mercury in the workplace air and determination by cold vapor atomic absorption spectrometry

A new KMnO4-MnO2solid multisorbent tube for capturing mercury in workplace air was developed.Experimental conditions for solid multisorbent tube,efficiency of sampling,desorption efficiency and stability were studied.Mercury and its compounds in air were captured by solid KMnO4-MnO2sorbent filled tube and desorbed with 0.90mol·L-1 sulfuric acid solution.Mercury and its compounds were quantitatively analyzed according to the method of GBZ/T 160.14—2004cold vapor atomic absorption spectrometry.The linear range of the proposed method was 0.000 2~0.015 0mg·L-1 with r=0.999 1,the average efficiency of sampling was 99.9%~100.0%in the concentration range of 0.001~2.820mg·m-3,and the breakthrough capacity was more than 505.4μg for 300mg KMnO4-MnO2solid multisorbent,the average recovery rate was 96.4%~103.8%, the intra-day and inter-day precision was 3.0%~3.3%and 3.5%~5.2%respectively,the limit of detection was 0.0013mg· m-3(7.5Lof air)and 0.000 6mg·m-3(96Lof air),after sampling,and the solid multisorbent tube could be kept at least 30 d at room temperature without significant loss.The present method was simple and suitable for capturing mercury and its compounds in the workplace air and ambient air.The solid multisorbent tube was useful for personal sampling and time weighted average sampling.