Abstract: Acetone is hydrogenated by a process comprising, conducting the liquid-phase hydrogenation of acetone in at least two hydrogenation process stages, thereby preparing isopropanol product with a high selectivity and in high purity.

Abstract: Phenol is separated from a mixture containing hydroxyacetone, cumene, water and phenol, by fractionating the mixture in a process with a fractional distillation step and a phase separation step to provide a single phenol fraction containing less than 300 ppm of hydroxyacetone. In the work-up by distillation of cleavage product mixtures, the hydroxyacetone can be removed from the cleavage product mixture together with a phenol fraction from which the hydroxyacetone has to be removed. A process can be used for purifying cleavage product mixtures obtained in the cleavage of alkylaryl hydroperoxides such as cumene hydroperoxide. The process allows separation of phenol and acetone from mixtures obtained in the cleavage of cumene hydroperoxide.

Abstract: The cleavage product from the acid-catalyzed cleavage of cumene hydroperoxide into phenol and acetone is subjected to thermal after-treatment by a process, which comprises heating the cleavage product in a reactor, wherein the heat supplied for the thermal treatment is the heat generated by at least one exothermic reaction which occurs in the reactor. The exothermic reaction which proceeds in the cleavage product is preferably the cleavage of cumene hydroperoxide.

Abstract: Impurities are removed from phenol by a process, comprising: first treating phenols containing impurities with at least one acid catalyst which converts the impurities into compounds which can be separated from phenol; separating the acid treated phenol from the compounds; and treating the distilled phenol a second time with at least one acid catalyst; thereby effectively removing the impurities from phenol.

Abstract: A process for reducing the salt content of fractions comprising high boilers obtained in the preparation of phenol from cumene, by extraction, is claimed. In the preparation of phenol from cumene, not only phenol and acetone but also by-products such as dimethyl phenyl carbinol or acetophenone are formed in the cleavage of cumene hydroperoxide. In the work-up of the cleavage product phase by distillation, these by-products are obtained as a fraction which boils only at high temperatures. These fractions further comprise alkali metal in the form of salts as a result of the neutralization by means of aqueous sodium hydroxide after the acid catalyzed cleavage. The presence of salt in this phase makes the work-up of this phase considerably more difficult. The salt is usually removed from the fraction by extraction of the fraction with water. However, considerable problems can occur if the aqueous phase cannot be cleanly separated from the organic phase.

Abstract: A process for the cleavage of alkylaryl hydroperoxides includes steps for producing a mixture of a concentrate that contains at least one alkylaryl hydroperoxide to be cleaved and a cleavage product obtained from the cleavage of an alkylaryl hydroperoxide, dividing this mixture into at least two parts and cleaving the alkylaryl hydroperoxides in parallel at different temperatures. One of the two parts is treated at a temperature sufficiently high for an integrated thermal post-treatment to be achieved. The process consumes less energy since less steam has to be used. Problems which can result from fouling in heat exchangers are largely prevented. No second feed point for alkylaryl hydroperoxide has to be provided. The process can be used in the preparation of phenol and acetone by the Hock method.

Abstract: Phenol is separated from a mixture containing hydroxyacetone, cumene, water and phenol, by fractionating the mixture in a process with a fractional distillation step and a phase separation step to provide a single phenol fraction containing less than 300 ppm of hydroxyacetone. In the work-up by distillation of cleavage product mixtures, the hydroxyacetone can be removed from the cleavage product mixture together with a phenol fraction from which the hydroxyacetone has to be removed. A process can be used for purifying cleavage product mixtures obtained in the cleavage of alkylaryl hydroperoxides such as cumene hydroperoxide. The process allows separation of phenol and acetone from mixtures obtained in the cleavage of cumene hydroperoxide.

Abstract: A process for the cleavage of alkylaryl hydroperoxides includes steps for producing a mixture of a concentrate that contains at least one alkylaryl hydroperoxide to be cleaved and a cleavage product obtained from the cleavage of an alkylaryl hydroperoxide, dividing this mixture into at least two parts and cleaving the alkylaryl hydroperoxides in parallel at different temperatures. One of the two parts is treated at a temperature sufficiently high for an integrated thermal post-treatment to be achieved. The process consumes less energy since less steam has to be used. Problems which can result from fouling in heat exchangers are largely prevented. No second feed point for alkylaryl hydroperoxide has to be provided. The process can be used in the preparation of phenol and acetone by the Hock method.

Abstract: A mass stream comprising mesityl oxide may be reacted with water in an acidic medium, a basic medium, or in the presence of an acidic catalyst, to convert the mesityl oxide to acetone. This process may be used in conjunction with the Hock process for manufacturing phenol and acetone to decrease the amount of mesityl oxide by-product, and increase the yield of acetone. Thus, cumene is oxidized to form cumene hydroperoxide, which is then cleaved in the presence of an acidic catalyst to form a cleavage product phase comprising phenol, acetone, and mesityl oxide. The cleavage product phase may then be distilled to provide a mass stream comprising mesityl oxide. At least some of the mesityl oxide of the mass stream is then, according to the process of the present invention, reacted with water, in an acidic medium, a basic medium, or in the presence of an acidic catalyst, thereby producing acetone.

Abstract: The cleavage product from the acid-catalyzed cleavage of cumene hydroperoxide into phenol and acetone is subjected to thermal after-treatment by a process, which comprises heating the cleavage product in a reactor, wherein the heat supplied for the thermal treatment is the heat generated by at least one exothermic reaction which occurs in the reactor. The exothermic reaction which proceeds in the cleavage product is preferably the cleavage of cumene hydroperoxide.

Abstract: Phenol and acetone are prepared by a process comprising homogeneously cleaving cumene hydroperoxide in the presence of acid catalyst in a cleavage apparatus comprising at least one reactor having plug flow characteristics thereby producing a cleavage product; recycling some of the cleavage product stream by combining the recycled cleavage product stream with the cumene hydroperoxide-containing feed stream fed to said cleavage apparatus under the condition that the mass flow ratio of the recycled partial cleavage product stream to the cumene hydroperoxide-containing feed stream sent to the cleavage reactor is less than 10.

Abstract: The present invention provides a method of starting up a loop reactor system, which method includes heating a reaction mixture present in the loop reactor system with the heat of reaction of at least one exothermic reaction occurring in the loop reactor system. The method of the invention makes possible an inexpensive, reliable and simple start-up of loop reactor systems, since the heat liberated when carrying out an exothermic reaction is utilized for heating the reaction mixture present in the loop reactor. Use of the method of the invention makes it unnecessary to switch heat exchangers over from coolant to heat transfer media such as steam. Since the method of the invention is able to heat up the reaction mixture in the loop reactor system more rapidly than in conventional methods, the number and the amount of by-products formed by secondary reactions during the start-up phase is reduced.

Abstract: A process for reducing the loading of wastewaters produced in the preparation of hydroxyl and carbonyl compounds from hydroperoxides by the Hock process, which may be acidic, by treating the wastewaters with an oxygen-containing gas at a pressure greater than 25 bar absolute and at a temperature of 150-250° C. Surprisingly, improved degradation rates are achieved under these conditions.

Abstract: The present invention relates to an improved method for producing phenol and acetone by oxidizing cumene into technical cumol hydroperoxide (CHP) through catalytic cleavage of the CHP. According to the invention, the oxidation products are concentrated to up to a cumene content ranging from 21 to 30 wt % in the technical cumol hydroperoxide, said mixture being used for the catalytic cleavage.

Abstract: The transportation and storage of phenol is enhanced by additions of up to 70% by weight of acetone to liquid phenol.