| 摘要 |
<p>An improved method of recovering sulfuric acid and methanol from contaminated spent, aqueous sulfuric acid solution comprising sulfuric acid, ammonium salts, methanol, organic compounds and water, obtained from a process for the manufacture of methyl methacrylate, said process comprising heating said spent solution to produce a second sulfuric acid solution having enhanced sulfuric acid concentration and an overheads mixture comprising methanol, formic acid and other light organic compounds and water; and recycling said mixture back to said methyl methacrylate manufacturing process, the improvement comprising (i) treating said aqueous mixture with a base to a pH of at least 7 to produce a non-acidic solution; and (ii) heating said nonacidic solution to provide a second mixture of reduced formic acid concentration and a residual liquor containing a formate salt. The invention provides reduced capital and operating costs in recycling sulfuric acid, methanol and water back to the methyl methacrylate manufacturing process.</p> |
