Detection method for trace methanol in water

Abstract

The present invention discloses a detection method for trace methanol in water. The detection method comprises: firstly preparing a calibration curve between the methanol concentration and the absorbance of a methanol aqueous solution, taking 10 mL of a water sample to be detected into a 25mL colorimetric tube, adding 2 mL of a dilute sulfuric acid aqueous solution with a volume percentage concentration of 25%, carrying out oscillation and uniform mixing, adding 0.5 mL of a potassium permanganate aqueous solution with a mass percentage concentration of 2%, uniformly mixing, standing for 5-30 min, adding a Na2SO3 aqueous solution with a mass percentage concentration of 5% in a dropwise manner until just fading, adding 0.2 mL of a chromotropic acid, uniformly mixing, finally adding 6 mL of concentrated sulfuric acid, uniformly mixing, carrying out water bath thermal insulation for 5-30 min at a temperature of 60-100 DEG C, taking out, cooling, diluting with deionized water to achieve a volume of 25 mL so as to obtain a complex solution of the water sample to be detected, determining the absorbance of the complex solution of the water sample to be detected at the wavelength of 570 nm by adopting deionized water as the blank control, and substituting into the standard curve to calculate the methanol concentration in the water sample to be detected.

Description

technical field [0001] The invention relates to a method for detecting trace amounts of methanol in water, in particular to a method for detecting trace amounts of methanol in water by spectrophotometry. Background technique [0002] Methanol, as an organic fuel, has attracted extensive attention from researchers due to its high energy density, ease of transportation and storage, in which electrocatalytic reduction of CO 2 Methanol production is a hotspot of current research. However, as far as the current research is concerned, the electrocatalytic reduction of CO 2 The efficiency of producing methanol is very low, the output is very small, and it is difficult to detect with general methods. Nowadays, the most commonly used method for detecting trace amounts of methanol in water is headspace gas chromatography, which uses headspace sampler, capillary chromatographic column, and FID detector to measure methanol in different concentration ranges from low to high in aqueous ...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to solve the technical problems of high detection cost, poor qualitative ability, and high pretreatment requirements of the sample to be tested in the above-mentioned trace methanol detection method in water, and provide a low operating cost, high measurement accuracy and sensitivity, and can A detection method for trace amounts of methanol in water that avoids the fluctuation of detection data caused by traditional gas chromatography due to the influence of ambient conditions such as room temperature

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