Mitsui Toatsu Chemicals, Incorporated

Daido Tokushuko Kabushiki Kaisha

Yoshio Morimoto

Takashi Kitamura

Shigeru Iimuro

Tsutomu Takase

Teruo Yuasa

Noboru Yamazaki

Minoru Hattori

Nobukatsu Kato

Nobukatu Kato

Takashi Kataoka

Tetsunosuke Shiomura

Hiroshi Ozawa

Satoshi Numata

Tetsuya Iwao

Kunio Hanauye

Takayuki Haruna

Toshio Itakura

Kunio Aoi

Nobukatsu Katoh

Akiro Ito

Sigeyuki Nasuda

Hiroo Inamori

Shigeru Imuro

A method for preparing high-purity bisphenol A which comprises a principal process comprising a first reaction step for reacting phenol with acetone, a first concentration adjusting step, a first crystallization step for precipitating crystals of the adduct of bisphenol A with phenol, a first separation step for separating a solution containing the crystals of the adduct into the crystals and the mother liquor and a phenol removing step for removing phenol from the crystals of the adduct; and a sub-process comprising a second reaction step for reacting p-isopropenylphenol with phenol, a second concentration adjusting step, a second crystallization step, a second separation step for separating a solution containing the second any crystals of the adduct into the second any crystals and the second mother liquor and a cleaving step, the first mother liquor from the principal process being fed to the sub-process and the second any crystals of the adduct from the sub-process being fed to the principal process, is herein provided. In addition, a method for preparing high-purity bisphenol A which comprises a principal process comprising a first reaction/catalyst removing step for reacting phenol with acetone and removing the catalyst, a crystallization step for precipitating the adduct of bisphenol A with phenol, a solid-liquid separation step for separating the reaction solution into the crystals of the adduct and the mother liquor and a phenol removing step for removing phenol from the adduct crystals; and a sub-process comprising a second reaction/catalyst removing step for reacting p-isopropenylphenol with phenol and removing the catalyst, a second phenol removing step, a distillation step for separating bisphenol A and low boiling and high boiling substances and a cleaving step, the mother liquor from the principal process being fed to the sub-process and the distilled bisphenol A from the sub-process being fed to the principal process, is also herein provided.

Process for preparing high-purity bisphenol A

A process for crystallizing the adduct of bisphenol A with phenol from a phenol solution in the presence of water comprises controlling the concentration of bisphenol A in said solution by removing portion of the phenol from said solution or adding phenol to said solution according to feedback control based on the measurement of solution density to obtain an adjusted solution, and feeding the adjusted solution to the crystallizer in which its inside wall is kept at a temperature higher than that of the adjusted solution, provided the temperature difference being smaller than 5.degree. C. The crystallized adduct has a uniform particle size and a high purity.

Process for crystallizing adduct of bisphenol A with phenol

A process for producing high-purity bisphenol A comprises reacting phenol with acetone in the presence of hydrochloric acid as the catalyst to obtain a product mixture, removing the hydrochloric acid from the product mixture, thereby yielding a liquid mixture, adding water to the liquid mixture, evaporating a water-phenol mixture from the liquid mixture under reduced pressure, thereby cooling the liquid mixture and crystallizing out the adduct of bisphenol A with phenol, and finally recovering bisphenol A from the adduct, wherein an improvement comprises treating the water-phenol mixture with a weakly basic ion-exchange resin and recycling and reusing the treated mixture as the water to be added to the liquid mixture. This process does not causes any troubles such as the corrosion of equipment and the decomposition and discoloration of bisphenol A during distillation.

Process for preparing bisphenol A

A process for producing high-purity bisphenol A comprises reacting phenol with acetone in the presence of an acid catalyst to obtain a product mixture, removing the acid catalyst from the product mixture, thereby yielding a liquid mixture, treating the liquid mixture with a weakly basic ion-exchange resin having pyridyl groups as the exchange groups, and purifying the treated liquid mixture. The process does not cause any corrosion of equipment and any decomposition and discoloration of bisphenol A during distillation.

A process for washing and obtaining solids of a slurry comprises feeding a slurry containing the adduct of bisphenol A with phenol crystallized from a phenol solution of bisphenol A to a first solid-liquid separator to separate solids from the slurry, transferring the solids separated by the first solid-liquid separator to an agitation tank in which the solids are reslurried, feeding the slurry obtained in the agitation tank to a second solid-liquid separator, said second solid-liquid separator being intended to obtain the solids from the slurry discharged from the agitation tank, and permitting the admission of a washing solvent to wash the solids, and permitting the filtrate and washings to be recovered independently, feeding the washing solvent to the second solid-liquid separator, feeding all of the washings from the second solid-liquid separator to the agitation tank, feeding a part of the filtrate from the second solid-liquid separator to the agitation tank, and discharging the remainder of the filtrate from the system. The process makes it possible to produce a high-purity adduct of bisphenol A with phenol and hence high-purity bisphenol A.

Process for washing and obtaining solids of slurry

In a process for producing bisphenol A by reacting phenol and acetone in the presence of hydrochloric acid as a catalyst, the improvement comprising adding the water-containing phenol separated from the reaction product mixture in the purification stage to the reaction mixture containing phenol and acetone, in such an amount that the water content in the reaction mixture is within the range of 1 to 5 wt%, said water-containing phenol being obtained from the dehydrochlorination step of the reaction product mixture, condensing the distilled off gases and liquid-separating of the condensates.

Process for producing bisphenol A

The process for preparing 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) by reacting acetone with phenol and decomposing the resultant adduct of bisphenol A and phenol is well known. However, the quality of bisphenol A thus obtained is not always satisfactory. In the process of this invention, the adduct is washed with phenol recovered by decomposing an adduct of bisphenol A and phenol, and then bisphenol A is prepared by decomposing the washed adduct. The bisphenol A prepared by the process of this invention has an extremely high quality and is suitable for the preparation of polycarbonate used for optical parts.

Process for preparing 2,2-bis(4-hydroxyphenyl)propane of high purity

A process for preparing high purity bisphenol A comprising feeding continuously phenol and acetone in the presence of a hydrochloric acid catalyst into a first stage reactor and reacting phenol and acetone in the range of 20-60 mol % of acetone conversion and continuously removing the first reaction product from the first stage reactor. The first reaction product is fed into a second stage reactor and the reaction of phenol and acetone is completed to obtain a second reaction product from which bisphenol A is recovered.

A process for obtaining high-purity bisphenol A by removing most part of phenol from an adduct of bisphenol A with phenol and removing continously the residual phenol by steam stripping, wherein a multi-tubular packed column is used as a stripping equipment. The residual phenol in bisphenol A can be removed constantly. In addition, the process of the present invention is economical because the residual phenol can be removed with a small amount of steam.

Process for obtaining high-purity bisphenol A

This invention is a process for the preparation of bisphenol A from acetone and phenol. By this invention, the formation of by-products is extremely decreased and post treatment steps can be simplified. This invention involves the following steps. (1) One mole of acetone is reacted with 4 to 12 moles of phenol in the presence of a sulfonic acid type cation exchange resin catalyst modified with a mercapto group-containing compound such as mercaptoethylamine to convert 20 to 60% of acetone, and (2) the reaction mixture containing unreacted acetone is successively reacted to the presence of the hydrochloric acid catalyst. The formation of by-products such as 2-(2-hydroxyphenyl)-2-(4-hydroxyphenyl)propane, Dianin's compound and the like is remarkably reduced by the process of this invention.

This invention relates to a process for preparing 2,2-bis(4-hydroxyphenyl)propane, e.g. bisphenol A and particularly to a process for preparing high quality bisphenol A with good workability by distilling the intermediate adduct of bisphenol A and phenol. The adduct of bisphenol A and phenol is fed to a distillation column. Phenol is recovered from the top of the column and bisphenol A is obtained from its bottom. In this distillation process, the adduct of bisphenol A and phenol is added with a part of recycled bottom liquid. Consequently troubles such as plugging of the distillation column are prevented, continuous operation becomes possible for a long period of time and high quality bisphenol A can be steadily obtained.

An apparatus for winding wire rods which are fed in succession from a rolling mill along a wire path, comprising: a carriage which is movable, at one end of the wire path remote from the rolling mill, in a direction perpendicular to the wire path; plural wire winders for winding the wire rods, the wire winders being mounted on the carriage such that the wire winders are disposed in the direction of movement of the carriage; and a device for moving the carriage to position selected so that one of the wire winders is in its winding position. A winding method is also disclosed, which comprises: positioning one of the wire winders at its winding position and winding the wire rod as a first coil by this one wire winder; upon completion of winding of the wire rod as the first coil, positioning the above one wire winder to its non-winding position before the leading end of the next wire rod fed from the rolling mill reaches the end of the wire path, and positioning another wire winder in its winding position; and winding the next wire rod as a second coil by this another wire winder, while concurrently taking out the first coil from the previously operated wire winder.

Method and apparatus for winding wire rod

An aromatic polyester amide is produced by reacting hydroxyphenyl-aminophenyl-propane with aromatic dicarboxylic acid dihalide in the presence of an inert organic solvent, and bringing the organic solvent phase containing the mixture of the reaction products of the above reaction into contact with an aqueous phase containing an acid-acceptor, whereby completing polycondensation reaction. In order to control the dissolution of water into the organic solvent phase while maintaining an adequate level of miscibility between the organic solvent phase and the aqueous phase, a neutral salt of inorganic electrolyte, such as sodium chloride, is added to the aqueous phase containing the acid-acceptor.

Process for producing aromatic polyester amide

A process for preparing 2-(4'-hydroxyaryl)-2-(4'-aminoaryl)-propanes of the general formula ##STR1## wherein R represents a hydrogen or halogen atom or an alkyl, aryl, nitro, nitrile, acyl, acyloxy or amino group, R.sup.1 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R.sup.2 and R.sup.3, independently from each other, represent a hydrogen or halogen atom, a nitro group or an alkyl group having 1 to 4 carbon atoms, which comprises reacting (A) at least one isopropenyl phenol compound selected from the group consisting of isopropenyl phenol derivatives of the general formula ##STR2## wherein R is as defined, and di- to eicosa-mers of said isopropenyl phenol derivatives with (B) an aromatic amine of the general formula ##STR3## wherein R.sup.1 , R.sup.2 and R.sup.3 are as defined, in the presence of 0.00001 to 0.008 mole, per mole of said isopropenylphenol compound (A) calculated as a monomer, of a acid catalyst and in the presence or absence of a phenolic solvent.

Process for preparing 2-(4'-hydroxyaryl)-2-(4'-aminoaryl)-propanes

Disclosed is a heat-resistant and fast-curing thermosetting resin composition suitably for insulating materials and comprising (a) a bismaleimide and/or a polymaleimide compound and (b) at least one compound selected from alkenylphenol derivatives, linear dimers thereof, and polymers thereof. In addition to components (a) and (b), this resin composition can contain (c) a polymerizable unsaturated compound.

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Tokai, Japan

Yoshio Morimoto