Production of food additive caustic soda

According to different uses, sodium hydroxide is divided into food grade, industrial grade and reagent grade. These three levels of execution * * The standards are: Food grade-GB5175-2008, the specific indicators are: NAOH≥98% Sodium carbonate≤0.5% Arsenic≤0.0003% Heavy metals≤0.002% Lead≤0.001% Insoluble matter and organic impurities passed the test Mercury≤0.00001% Use: Food processing, preserved egg production, dry seafood soaking, pharmaceutical industry and condiment production. In the food industry, it is mainly used as an acidity blending agent. It can also be used for cleaning wine bottles and grain and oil containers. Industrial grade-GB209-2006, the specific indicators are: NAOH≥98-99% Sodium carbonate≤0.5-1% Sodium chloride≤0.03-0.08% Ferric oxide≤0.005-0.01% Usage: Very wide, including but not limited to manufacturing chemicals, papermaking, aluminum smelting, tungsten smelting, rayon, rayon and soap manufacturing, pesticides, dyes, rubber, petroleum industry, as well as national defense, machinery, wood, metallurgy, medicine, urban construction, water electrolysis and inorganic salt production, etc. Reagent grade - GB/T 629-1997, specific indicators: NaOH≥98.0% Chloride≤0.005% Sulfate≤0.005% Total nitrogen≤0.001% Phosphate≤0.001% Silicate≤0.01% Carbonate≤1.5% Aluminum≤0.002% Potassium≤0.05% Calcium≤0.01% Iron≤0.001% Heavy metal≤0.003% Usage: Experimental reagent, can also be used as alkaline desiccant. Summarize: Industrial grade has no heavy metal index restrictions, and food grade heavy metal index requirements are higher than reagent grade.