Determination of Volatile Sulfur Compounds in Livestock Waste Compost by Gas Chromatography-ion Mobility Spectrometry

A method for determination of volatile sulfur compounds-dimethyl sulfide, diethyl sulfide, dimethyl disulfide, and carbon disulfide in livestock waste compost was established using gas chromatography–ion mobility spectroscopy technology. The sample was collected using a gas sampling bag after ammonia removal, separated on a packed gas chromatography column of MXT-1, and detected in both positive and negative modes under the optimized experimental conditions. The results showed that the four sulfur compounds represented good linearity (R²>0.99) in their respective linear ranges; the detection limits were 0.008~0.097 mg/m³ with recoveries of 85%~116% and relative standard deviation (RSD) of 1.13%~8.42%. The method is free of pretreatment such as pre-concentration or enrichment, sensitive and rapid, and the collection of odorous composting gas can be conducted using a gas sampling bag. The method is sensitive and rapid, which can be used for on-site monitoring of volatile sulfur in compost gas.