摘 要:采用稱量法配制了異丁烷、二氯甲烷、苯等16種室內揮發性有害有機物的混合標準氣體,各物質濃度為1ppm,平衡氣為氮氣。標準氣體采用天平稱量定值,通過實驗室內和實驗室間氣相色譜法比對分析考察其配制準確性,并通過各物質濃度隨時間及瓶內壓力的變化考察了其濃度的均勻性和穩定性。結果表明我們研制生產的室內揮發性有害有機物混合標準氣體量值準確,均勻性、穩定性好,各項技術指標滿足國家對二級標準物質的要求。
關鍵詞:重量法;混合標準氣體;定值;均勻性;穩定性
中圖分類號:TB99 文獻標識碼:A 文章編號:1672-4984(2007)01-0001-04
Preparation of 16 hazardous VOCs standard mixture
TAN He-ping, SUN Deng-feng, FANG Zheng, MA Tian
(National Institute of Measurement and Testing Technology,Chengdu 610021,China)
Abstract:1ppm Hazardous VOCs standard mixture containing 16 compounds such as i-butane,dichloromethane,benzene,etc.in UHP nitrogen was prepared by gravimetric method. The results of GC analysis and the compare among these results of few laboratories were used to confirm the accuracy of the gravimetric preparation.Relationships between time or pressure and uniformity or stability were also investigated. Thess results indicated that concentrations of those mixture compounds in cylinder are accuracy,uniform and stable,which can fulfill requirements of Warrant Reference Materials(WRM) absolutely.
Key words:Gravimetric method;Standard mixture;Concentration analysis;Uniformity;Stability