METHOD FOR PREPARING SECONDARY BUTYL ALCOHOL Russian patent published in 2003 - IPC

FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to the improved method for preparing secondary butyl alcohol that is an intermediate product for production of methyl ethyl ketone. Method involves liquid-phase alkylation of n-butenes taken as butane-butene fraction with acetic acid to yield sec.-butyl acetate, the following hydrolysis in the presence of immobile layer of catalyst sulfocationite resin in H⁺-form to yield sec.-butyl alcohol and acetic acid and isolation of sec.-butyl alcohol in system of fractionating columns where firstly mixture of sec.-butyl alcohol. Sec. -butyl acetate and water is separated from acetic acid aqueous solution, the following water removal from this mixture and separation of mixture of sec.-butyl alcohol and sec.-butyl acetate to isolate sec.-butyl alcohol. Hydrolysis of sec. -butyl acetate is carried out into vertical hydrolysis reactor with catalyst layer height 3-12 m where sec.-butyl acetate and water are fed by countercurrent with volume feeding rate 0.42-0.51 h^-1 and extraction of formed sec.- butyl alcohol and acetic acid with unreacted sec.-butyl acetate is carried out and water is fed in the amount compensating its consumption for hydrolysis reaction and for its dissolving in an organic extract. Separation of mixture of sec.-butyl alcohol, sec.-butyl acetate and water from an aqueous acetic acid is carried out in column of azeotropic rectification with efficiency 20-30 theoretical plates by such manner to provide temperature on control plate of exhausting part of column maintaining at the level 101.5-103.9 C in feeding heating steam into vat in the amount corresponding to specific consumption 0.507-0.517 kg/kg of raw. The following removal of water from mixture of butyl alcohol, sec.-butyl acetate and water in column of azeotropic drying with efficiency 22-30 theoretical plates is carried out by manner to provide temperature on control plate of concentrating part of column maintaining at the level 96.1-98.8 C in feeding heating steam into vat in the amount corresponding to specific consumption 0.576-0.702 kg/kg of raw with removal of organic phase in the range from 1.4 to 4.5 wt.-% of amount the raw feeding into this column. Further, the prepared dried mixture of sec.-butyl alcohol and sec.-butyl acetate is separated into fractionating column with efficiency 50-60 theoretical plates with isolation of sec.-butyl alcohol and from distillate of azeotropic drying impurities of low- boiling alcohols formed in hydrolysis and isolation of butene dimmers from an aqueous phase and from part of organic phase on additional fractionating column with efficiency 20-28 theoretical plates and with recovery of vat hydrolysis product from this column into reactor. Method provides to prepare sec.-butyl alcohol of high quality, to provide stable work of the hydrolysis reactor and to simplify the operation process. EFFECT: improved preparing method. 6 cl, 10 tbl, 1 dwg, 61 ex