Caustic soda is a highly alkaline inorganic compound represented as NaOH. It is widely used in many industries like paper, pulp, soaps, textiles, water, etc. Globally the demand for caustic soda is increasing day by day. It is usually manufactured by the chloralkali process. The usual method is to combine calcium hydroxide and sodium carbonate to produce caustic soda and by-product calcium carbonate. Caustic soda is usually sold in the form of prills, flakes, cast blocks, and sometimes also as granules and as tablets. It is a highly versatile substance, used in making a wide range of products that we use every day- like soaps, detergents, paper, etc. It is used in electroplating extraction, oxide coating, metal cleaning, processing dyes in the textile industry, manufacture cotton fabric, producing aluminum products, etc.
China, Japan, Taiwan, and the USA are some of the countries that export caustic soda in huge amounts, with the largest consumer being the paper and pulp industry, followed by inorganic chemical manufacturers, then organic chemical manufacturers and lastly alumina extraction processes. Supply of Caustic soda sometimes depends on the chlorine market, there have been times where caustic soda prices get higher while chlorine prices decline tremendously.
Caustic soda is highly alkaline and hydrophilic in nature. This property makes caustic soda corrosive to animal and plant tissues. It is non-volatile and inflammable. When caustic soda comes in contact with the eye, it should be immediately treated as consequences can be bad.
Caustic soda is considered to be corrosive, so it must be handled carefully. It is advised to use protective goggles, gloves and safety clothing while handling caustic soda. For bulk quantities storage, PVS, stainless steel or HDPE coated drums or tanks are used. While handling in bulk, water supply should always be available near the point of use. Typical protective equipment used while handling caustic soda is PVC elbow-length gloves, complete overalls, face shield, etc.
Applications of Caustic Soda
- In petroleum industry – Used as an additive to increase the alkalinity of the mud system and to neutralize the acidic gases produced during drilling.
- In the paper industry – Used in pulping wood and generating fibers from wood. It is also used in the kraft process as a bleaching agent in paper production.
- In food industry –
- Used in washing and chemical cleaning of vegetables and fruits
- Used in cocoa and chocolate powder production
- Used in producing cold beverages and soft drinks
- Used in baking industry for thickness of crusts on breads
- In water treatment – To raise the pH of water, sodium hydroxide is added for water treatment to reduce the amount of copper, lead and other toxic metals.
- In the construction industry – Sodium hydroxide suppliers use sodium hydroxide as cement plasticizers for homogenizing cement mixes and increase the workability of cement.
- In the cleaning industry – Sodium hydroxide is added to surfactants as it can easily dissolve fats, grease, oils etc.
- It is used in manufacturing several other organic products and acts as one of the primary reactants.
- Caustic soda is used in aluminum and bauxite ore extraction process.
- Other applications of Caustic soda include rubber recycling
Other than the above mentioned uses, sodium hydroxide is used in many more applications as defoamers, as flame retardants, as ion exchange agents, as pigments, as oxidizing and reducing agents, as lubricants etc. We at Tradeasia collaborate with top Caustic Soda suppliers for our huge customer base across South-East Asia.