PRODUCT PROFILE Diphenyl oxide is the parent molecule of brominated diphenyl ether flame retardants. It is used as a high boiling solvent to purify pharmaceuticals. It is used as a starting material for the preparation of heat transfer fluid, specialty surfactant, and blowing agents. Diphenyl oxide is not readily biodegradable. There is no evidence that harmful products are formed as a result of biodegradation. Diphenyl oxide is moderately toxic to fish and other aquatic organisms. It is irritating to eyes, respiratory system and skin. Several polybrominated diphenyl ethers (PBDEs) are useful flame retardants. It is synthesized by a modification of the Williamson ether synthesis, here the reaction of phenol and bromobenzene in the presence of base and a catalytic amount of copper. Involving similar reactions, diphenyl ether is a significant side product in the high-pressure hydrolysis of chlorobenzene in the production of phenol. Product characteristics â€¢ Chemical Name : Diphenyl Oxide; 1,1'-Oxybisbenzene; Phenyl ether; . Phenyl Ether; Oxyde de biphenyle, Diphenyl Ether. â€¢ CAS Number : 101-84-8 â€¢ Molecular Weight : 170.21090000 â€¢ Formula : C12 H10 O or C6H5OC6H5 â€¢ Melting Point : 28oC â€¢ Flash point : 115 Â°C (388.15 K) â€¢ Freezing point : 26. 5Â°C The process of preparing diphenyl oxide from chlorobenzene: The process of preparing diphenyl oxide from caustically hydrolyzing chlorobenzene wherein phenol is a by product, is improved by recycling the phenol. The improvement not only maximizes the yield of diphenyl oxide while minimizing the yield of phenol, but it also increases the yield of desirable by products, such as phenylphenols and biphenylylphenyl ethers. APPLICATIONS OF Diphenyl oxide: â€¢ Diphenyl oxide can be used into preparation of perfumery compounding, Soaps, Detergents, and Agarbatthi. â€¢ Diphenyl oxide can be used as a high boiling reaction solvent in the manufacture of drugs like Chloroquine Phosphate (anti malarial drug), Norfloxacin, Pefloxacin, Ciprofloxacin (broad spectrum antibiotics) etc. â€¢ Diphenyl oxide on bromination gives Deca Bromo Diphenyl oxide which is widely used in the plastics industry as a fire retardant. â€¢ Diphenyl oxide along with Diphenyl forms a heat transfer fluid, which is used at temperatures as high as 400 Â°C. â€¢ Diphenyl oxide is used in the manufacture of alkylated Diphenyl oxide Di Sulphonate, a speciality surfactant which finds application in textiles, mining, petroleum, agriculture etc. â€¢ The main application of diphenyl oxide is as a eutectic mixture with biphenyl, used as a heat transfer medium. Such a mixture is well-suited for heat transfer applications because of the relatively large temperature range of its liquid state. â€¢ Diphenyl ether is also used as a processing aid in the production of polyesters. GLOBAL SCENARIO: Present global production level of diphenyl ether is around 65000 tonnes per annum. Diphenyl oxide, or DPO, is a key raw material in the production of a variety of industrial products such as surfactants, flame retardants, fragrances, chemical intermediates and heat transfer fluids. DPO is an essential ingredient used to manufacture Therminol VP-1 heat transfer fluid, the heat transfer fluid of choice for the solar industry. Global demand of diphenyl oxide is increasing and hence its production is likely to increase in next few years.