Sodium hydroxide, NaOH, also known as lye or caustic soda, is an extremely caustic (corrosive and damaging to human tissue) white solid that readily dissolves in water. Sodium hydroxide is used in the manufacture of soaps, rayon, and paper, in petroleum refining, and in homes as drain cleaners and oven cleaners. Sodium hydroxide is one of the strongest bases commonly used in industry. Solutions of sodium hydroxide in water are at the upper limit (most basic) of the pH scale. Sodium hydroxide is made by the electrolysis (passing an electric current through a solution) of solutions of sodium chloride (table salt) to produce sodium hydroxide and chlorine gas. Other uses include the manufacturing of plastics by dissolving casein, in reclaiming rubber by dissolving out the fabric, peeling fruits and vegetables in food production and in vegetable oil refining, and etching and electroplating. Sodium hydroxide also has applications in chemical and metal processing, the pulp and paper industry, disinfection, and to dehorn cattle
Two of the more common household products containing sodium hydroxide are drain cleaners and oven cleaners. When most pipes are clogged it is with a combination of fats and grease. Cleaners that contain sodium hydroxide (either as a solid or already dissolved in water) convert the fats to soap, which dissolves in water. In addition, when sodium hydroxide dissolves in water a great deal of heat is given off. This heat helps to melt the clog. Sodium hydroxide is very damaging to human tissue (especially eyes). If a large amount of solid drain cleaner is added to a clogged drain, the heat produced can actually boil the water, leading to a splash in the eyes of a solution caustic enough to cause blindness. Some drain cleaners also contain small pieces of aluminum metal. Aluminum reacts with sodium hydroxide in water to produce hydrogen gas. The bubbles of hydrogen gas help to agitate the mixture, helping to dislodge the clog.
Oven cleaners work by converting built up grease (fats and oils) into soap, which can then be dissolved and wiped off with a wet sponge.
Sodium hydroxide is used to neutralize acids and as a source of sodium ions for reactions that produce other sodium compounds. In petroleum refining it is used to neutralize and remove acids. The reaction of cellulose with sodium hydroxide is a key step in the manufacturing of rayon and cellophane.
The primary stationary sources that have reported emissions of sodium hydroxide in California are pulp mills, public order and safety facilities, and manufacturers of aircraft and aircraft parts.
Sodium hydroxide is registered as an adjuvant for agricultural use, and as an algaecide for use in industrial waste disposal systems and sewage systems. The licensing and regulation of pesticides for sale and use in California are the responsibility of the Department of Pesticide Regulation (DPR).
Physical Properties of Sodium Hydroxide
Molecular Weight: 40.00
Boiling Point: 1390 oC
Melting Point: 318.4 oC
Vapor Pressure: 1 mm at 739 oC
Density/Specific Gravity: 2.120 at 20/4 oC (water = 1)
Log Octanol/Water Partition Coefficient: Too low to measure
What can be greener and cheaper source than see water ( or brine) and windpower for electrolysis? The chlorine containing by-products are used in large scale in disinfection of sweet (drinking water). See for example;
https://www.google.hu/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAcQjRw&url=http%3A%2F%2Fwww.essentialchemicalindustry.org%2Fchemicals%2Fchlorine.html&ei=ScfCVKiOL8PjO_WDgbgD&psig=AFQjCNER9hlh6pddNwk85Q6v3m0yGbKTBw&ust=1422137279879390
NaOH is commercially produced by Electrolysis of NaCl Solution (Brine).
Because NaOH is a byproduct of chlorine production, it's 100% green, in the sense that your use of it will not add anything to the world's waste stream. Caustic production is driven entirely by the demand for chlorine. You could use thousands of tons of NaOH, and the only consequence would be higher demand and a marginally higher price.
Sources of sodium hydroxide is inorganic compound we use for hydrolysis as it gives Na cation & OH anion. So water will be the green source for getting hydroxide anion.
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