Sodium hydroxide is primarily used in papermaking, the production of cellulose pulp, and the manufacturing of soap, synthetic detergents, and synthetic fatty acids, as well as the refining of animal and vegetable oils. In the textile printing and dyeing industry, it is used as a desizing agent, scouring agent, and mercerizing agent for cotton fabrics. In the chemical industry, it is employed in the production of borax, formic acid, oxalic acid, phenol, and others. In the petroleum industry, it is used for refining petroleum products and in oilfield drilling mud. It is also utilized in the production of alumina, surface treatment of metals such as zinc and copper, and in the glass, enamel, leather tanning, pharmaceutical, dye, and pesticide industries. Food-grade products are used in the food industry as acid neutralizers, as peeling agents for citrus fruits and peaches, and as cleaning agents for empty bottles, cans, and other containers.