caustic soda

Sodium hydroxide (NaOH), also known as lye or caustic soda, is a caustic metallic base. An alkali, caustic soda is widely used in many industries, mostly as a strong chemical base in the manufacture of pulp and paper, textiles, drinking water, and detergents. Worldwide production in 1998 was around 45 million tons. Sodium hydroxide is also the most common base used in chemical laboratories, being able to test for quite a number of cations (this is called Qualitative Inorganic Analysis), as well as to provide alkaline mediums for some reactions that need it, such as the Biuret test. The capacity of caustic soda in China reached 12.4 million t/a in 2004 and the output was 10.6026 million tons, with an increase of 13.6％ over the previous year. Of the total, the output of ion-membrane process caustic soda was 2.5246 million tons, with an increase of 12.8％ over the previous year, and the reminder was diaphragm process caustic soda. Most caustic soda projects that are being constructed or expanded are ion-membrane process units. The output growth of ion-membrane process caustic soda will account for the major share in the output growth of caustic soda in China in the next few years.