SU956447A1 - Process for producing diphenylol propane - Google Patents

Description

The goal is achieved by carrying out co-condensation of three 80-90 ° С with simultaneous distillation of water as an azeotrope with a hydrocarbon selected from the soil: benzene, cyclohexane, chlorobenzene, using 1–5 May. % 94-96% siloy. Acid with respect to the original phenol.

This process provides a constant HIGH Concentration of the catalyst in the Continuous Batch of Acetone and the Continuous Dissipation of the Reaction Water with Heterose-Forming Agents. , At: the change of these compounds maintains the temperature of the process in the ratios of 80-90 ° C (the boiling point of the reaction mixture) and / at the end of the process they are easily separated from the reaction medium by distillation.

Continuous supply of acetone provides in the reactor at any given time a large molar ratio of phenol and acetone, which reduces the possibility of formation of by-products and increases the yield of the target product.

In the well-known method of carrying out condensation in the presence of 96% sulfuric acid, diphenylollopropane is not formed even for a long time (2 days) and the reaction mass contains only the product of sulfonation of phenol.

When using the same concentrated sulfuric acid in the amount of 1-5 May. % and 1 at the boiling point of the reaction mixture, the actual catalyst is phenolsulfonic acid, which is formed by IB at the beginning of the sulfonation process of the starting phenol (this is proved by differential titration).

Formed with phenolsulfonic acid, in contrast to ot of sulfuric acid, has a higher solubility in the reaction mixture, which ensures a higher reaction rate. Condensacin; sulfonation of condensation products is excluded, which allows the use of higher rates in the process.

Example 1. Obtaining diphenylolpropane in the presence of 2 may. % 96% sulfuric acid And 1 May. % thioglycolic acid at a molar ratio of phenol:: (acetone, equal to) M 4: 1, In a flask equipped with a stirrer, a thermometer, a Dean-Stark trap with reflux condenser and a capillary to supply 33% (by volume) acetone to cyclohexane, load 94 g of phenol (1 mol), 2.55 g of sulfuric acid, 1.35 g of thioglycolic acid, 50 ml of cyclohexane. The reaction mixture was agitated with stirring until boiling (86-88 ° C). After all the water is released from the sulfonation of phenol (20-30 min), 50 ml of acetone in cyclohexane (0.25 mol of acetone) are gradually introduced over 3 hours, maintaining the temperature required to remove the water. The water released as a result of the sulfonation and condensation reactions is distilled from the reaction mixture from steam, m (and cyclohexane-water heteroazeoprope — water, condensed in a refrigerator, and stratified in a Dean-Stark nozzle. At the same time, the hydrocarbon layer is returned to the reactor and the water is as you accumulate the output through the Dean-Stark trap. After refining-feeding the acetone solution into cyclohexane, the latter is distilled off, and from the reactor also through the Dean-Stark trap.

At the end of cyclohexane distillation at 80-90 ° C, phenolsulfonic acid (FGC) is extracted with water, which is added in such an amount that the extractable FGC concentration in the extract is no less than 45-50% by weight. For a better separation of CSF from the hydrocarbon layer, a small amount of toluene (15-25 ml) is added. In this case, the extract is extracted; the whole FGC and its 40-50% piacTBop in B1od after concentration can be used in the condensation process as a catalyst.

The balance of FGC in the hydrocarbon layer is neutralized with a 10% solution of concentrated soda.

After separation of the condensation products by known methods (rectification, recrystallization), 54.7 g of diphenylolpropane (0.24 mol) are obtained,

46.5 g of unreacted phenol (0.495 mol). In this case, the conversion of acetone is 99.4%, the yield of diphenylolpropane per propane-reactive acetone is 96.4 mol. %, Hia reacted phenol - 95, l%, so pl. selected dnviwilolpropane 156 ° C.

Example 2. Obtaining diphenylolpropane in the presence of 5 May. % sulfuric acid at a molar ratio of phenol:: acetone, equal to 4: 1.

The reaction procedure is as in Example 1. A load of 94 g (1 mol) of phenol, 50 ml of cyclohexane, 6.9 g of sulfuric acid, 1.353 g of thioglycolic acid was loaded. Then, 55 ml of a 33% aqueous solution (by volume) of acetone in cyclohexane (0.25 mol of acetone) are gradually introduced over 3 hours.

The acetone conversion is 99.65%. After the isolation of diphenylolpropane, 54.5 g of diphenylolpropane (0.239 mol) and 49.1 g (0.522 mol) of unreacted phenol are obtained. The output of diphenylolpropane on reacted. acetone is

95.6 mol :%

Claims (3)

EXAMPLE 3. Preparation of diphenylolipan in the presence of I 1mass. % sulfuric acid, 1 May. % thioglycolic acid at a molar ratio of phenol: acetone, equal to 4: 1. Reaction procedure, as in Example 1. Charged with 94 g (1 mol) of phenol, 50 ml of cyclohexane, 1.4 g of sulfuric acid, 1.32 g of thioglycolic acid. Then, gradually, over 3 hours, 55 ml of a 33% acetone solution in cyclohexane are introduced. Acetone conversion is 65.8%. Example 4. Obtaining diphenylolpropane iB tri-presence on 2 May. % sulfuric acid; instead of cyclohexane, benzene is used (i.e., aepotropic acid with water, 69.2 ° C, composition: 29.8 mol.% of water). The method of conducting the experiment and zagruak as in Example 1. The boiling point of the reaction mixture is 85-87 ° C. Acetone conversion is 99.53%. After isolation, 54.3 g of the desired product (0.238 mol) and 46.95 g (0.4995 mol) of unreacted phenol are obtained. The yield of diphenylolpropane is 95.65 mol. % 1 reacted acetone and 95, il mol. % on phenol. Example 5. Obtaining diphenylolpropane in the presence of 2 may. % sulfuric acid; Chlorobenzene is used as an azeotrophobic agent (t. kil. azeotrope with water is 90.2 ° C; composition: 28.4% by weight of water). The test procedure and loading, as in example 1. The boiling point of the reaction mixture is PO-115 ° C. Conversion of acetone is 99.4%. After isolation, 48.31 g of diphenylolpropane (0.2119 mol) and 47.03 g of unreacted phenol (0.5003 mol) are obtained. The yield is 84.8 mol. % on the reacted phenol and 85.3 mol. % on the reacted acetone. The method of obtaining diphenylolpropane by condensation of phenol with acetone in the presence of sulfuric and thioglycolic acids, characterized in that, in order to accelerate the process and increase the yield of the target product, the process is carried out at a temperature of 80-90 ° C with simultaneous distillation of water as an azeotrope with hydrocarbon Selected groups: benzene, cyclohexane, chlorobenzene, using 1–5 May. % 94-96% sulfuric acid relative to the initial phenol. Sources of information taken in. attention during ecopertize: L Verkhovska 3. N. Diphenylolpropane. M., “Khimp, 1971, p. 5-6. 2. There & p. 141. 3. In the same place 108-111 (prototype).