Chemical Process

Sodium Hydrosulphide Sodium Hydrosulphide (NaHS) finds use in ore flotation (30 percent), dyestuff processing (20 percent), as a leather depilatory (20 percent), the manufacture or rayon and organic chemicals (10 percent) and in the metallurgical industry. These were five merchant producers who operated six plants in 1981. Total demand was about 18,000 t/year. Wow very big amount. Sodium Thiosulfate Sodium Thiosulfate crystallizes in large, transparent, extremely soluble prisms with five molecules of water. It is a mild reducing agent, like sodium sulfite. It is employed as an antichlor following the bleaching of cellulose products and as a source of sulphur dioxide in the bleaching of wool, oil, and ivory. In photography, which accounts for 90 percent of current use, it is used to dissolve unaltered silver halogen compounds from negatives and prints, where it is commonly called “hypo”. It is a preservative against fermentation in dyeing and serves in the preparation of mordants....

Insect have more species (over one million already described) than any other form of animal life and are in many ways the most indestructible form. About 1 percent of the species offer hazard to human and animals. Human and pests fight a continuous battle for food and shelter. Insects alone claim about 10 % of our crops in US, and about 14 percent in worldwide, various misery causing diseases are carried by insect malaria, yellow fever, typhus, and plague to name a few. For us to survive at current population levels, pesticides must be used and new ones constantly developed. When insecticide applied widely, all but a few of the local insects are destroyed, but the remaining ones are those most resistant to the destroying agent. After destroying generation, this selection makes the surviving insects increasingly resistant to the destroying agent. Eventually, complete resistance may occur. This phenomenon is seen with medical product, and all types of pesticides. In an effort to retard ...

Sodium Sulfite Sodium sulfite is a compound that is very easily oxidized. For this reason, it is employed in many cases where a gentle reducing agent is desired, e.g. to bleach wool and silk, as an antichlor after the bleaching of yarns, textile and paper, as a preservative for foodstuffs, and to prevent raw sugar solution from colouring upon evaporation. It is very widely used in the preparation of photographic developer to prevent from oxidation from hydroquinone and other agents. It has a small application in the field of medicine as an antiseptic and as an antizymotic for internal use. About 60% of the total merchant market is in the paper Industries. While merchant capacity is about 145,000 t/year, the paper mills have twice capacity to captive use. The demand for boiler feed water treatment is about 15%. It is use to remove oxygen from water and thus help to prevent corrosion and scale formation. These were four major production in 1891, one of which provided 50% percent of the...