1results about How to "Three wastes less pollution" patented technology

The invention discloses a synthetic method of a water soluble ultraviolet light absorber BP-9. The method mainly comprises the following process steps: (1) carrying out methylation on the main raw materials of 2, 2', 4, 4'-tetrahydroxyl benzophenone, a transition metal salt catalyst and a mixed solvent which is prepared from dichloroethane and anhydrous ethanol in equal parts by weight to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone; (2) carrying out sulfonation reaction on the main raw materials of methylate, sulfamic acid and C1-C3 halohydrocarbon to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone-5, 5'-disulfonic acid; and (3) carrying out neutral reaction on the main raw materials of sulfonated product, inorganic base and ethanol water to finally obtain the BP-9 product. The synthetic method disclosed by the invention is few in reaction step, low in cost, high in product purity and stable in quality, and raw materials are easily available.