Instruments capable of measuring the moisture content in various organic and inorganic solid, liquid, and gas samples are called moisture analyzers. Based on the measurement principle, they can be classified into two major categories: physical measurement methods and chemical measurement methods. Commonly used physical measurement methods include the loss-on-drying method, distillation layering method, and gas chromatography analysis, among others. Chemical measurement methods mainly include the Karl Fischer method and the toluene method. The International Organization for Standardization has designated the Karl Fischer method as the international standard for measuring trace moisture, and our country has also adopted this method as the national standard for measuring trace moisture.