用分光光度法测定空气和水中的甲醇

Determination of Methanol in Air and water by Spectrophotometry

提出测定裂气和水中甲醇的灵敏的分光光度法。甲醇先氧化成甲醛,然后在酸性介质与铬变酸在曲拉通X-100表面活性剂存在下生成兰紫色配合物。比尔定律适用范围为10～100μg甲醇/10ml。最大吸收波长为574 nm,摩尔吸光系数ε为8.2×10~3L·mol^(-1)·cm^(-1)样品5次测定平均相对误差为+1％～-1.5％。

A sensitive spectrophotometric method for determinig methanol in air and water is described. The methanol is oxidized to formaldehyde which is then determined in acidic medium with chromotropicacid, and a blue-purple coordination compound forms in the presence of Triton X-100 as a surfactant. Beer's law is obeyed in the range 10-100 μg of methanol in 10ml, the wavelength of maximum absorption is 574 nm, and the molar absorptivity is 8.2x10^3 (L·mol^(-1)·cm^(-1)). The avarage ralative error for five determination is form+1% to -1.5%.