How to distingush sodium hydroxide

Sodium hydroxide is a kind of alkali with strong corrosive, generally they are flake or pellet form, easily soluble in water, and forms alkaline solution. It is hygroscopic, easy to absorb water vapor in the air (hygroscopic) and carbon dioxide (metamorphic), hydrochloric acid can be added to verify deterioration. Sodium hydroxide (NaOH) can be used as alkaline cleaning agents in water treatment to be dissolved in ethanol and glycerol, but it is insoluble in alcohol and ether.

Food grade sodium hydroxide is different from food grade sodium bicarbonate. Sodium hydroxide is a strong alkali substances with a certain amount of corrosive chemicals. And baking soda is a weak alkaline substances, it is hardly has any corrosion. Sodium hydroxide is usually used as food processing additives, and it will not have any residues after processing. While sodium bicarbonate is mainly used in the flour products food additive, the function is fluffy. So the two kinds of food additives uses are not the same. As to sodium hydroxide for industrial use and food grade use, the purity is different. The industrial use sodium hydroxide is low purity and may contain substances harmful to the human body, which is not allowed in food grade sodium hydroxide.

Generally, the presence forms of sodium hydroxide are rendered in white translucent crystalline flake, of course, some manufacturers according to customer's need to produce sodium hydroxide with different shapes, such as granular. Due to the special physical and chemical properties of sodium hydroxide, for example, it has a very strong water absorption and moisture absorption function, this indicate that one of its applications is similar to lime and can be used as a desiccant. Because of its strongly alkaline, it can be applied to cooking and bleaching papers. Food grade sodium hydroxide can be used as processing of starch as a catalyst.

But how it is stored, as well as during transport the attention? Industrial use solid caustic soda are packaged by metal pail or other airtight, the metal pail wall thickness is above 0.5mm, pressure resistance is 0.5Pa, the lid must be sealed solid barrel, etc. There should be clear symbol of "corrosive" on the packaging. Food liquid caustic soda load by tank wagon, it must be clean well after use two times. Do not allow shipment of liquid mercury-electrolysis of caustic soda tank wagons or tank, barrel shipping edible liquid caustic soda. There should be clear words of "food additive" and symbol of "corrosive". If you have interest, please get more about okchem here, thanks!