Ube Industries, Inc.

Kanji Nakagawa

Kohei Ninomiya

Makoto Matsuo

Masayuki Kinouchi

Hiroshi Makino

Hiroshi Shimazaki

Toshikazu Machida

Shigeru Yamamoto

Kohei Nakajima

Yoshio Asakura

Hiroshi Shimada

Toshio Maruyama

Yoichi Nishida

Koji Miyauchi

A catalyst for dimerizing a lower .alpha.-olefin monomer with an enhanced selectivity comprises a carrier comprising at least one anhydrous potassium compound, preferably a mixture of potassium fluoride with potassium carbonate, and a carbon material; and a catalytic component carried on the carrier and comprising an alkali metal, preferably sodium metal, the catalyst preferably being compression molded into grains.

Catalyst for dimerizing .alpha.-olefin monomer

A lower alcohol, for example, ethyl alcohol, is recovered from a reaction mixture resulted from a reaction of catechol with a lower alcohol in such a manner that the reaction mixture is distilled and separated into a distilled light vapor fraction comprising non-reacted lower alcohol and water and a residual fraction comprising a reaction product and non-reacted catechol; the distilled light vapor fraction is further distilled and separated into a distilled vapor fraction comprising the lower alcohol in an increased concentration and a residual water fraction; the distilled vapor fraction is fed to a gas-separating membrane module which allows water vapor to selectively permeate therethrough, and separated into a non-permeated fraction which comprises the lower alcohol in a high concentration, which is left in the feed side of the membrane, and a permeated fraction which comprises water in a high concentration, which is returned from the delivery side of the membrane to the further distilling step, and the non-permeated fraction is cooled and recovered.

Process for recovering a lower alcohol from a catechol-lower alcohol

An improved method for dehydration and concentration of an aqueous solution containing an organic compound is disclosed. The solution is evaporated to produce a gaseous mixture comprising an organic compound vapor and a water vapor. The water vapor is selectively removed from the gaseous mixture by permeation through an aromatic polyimide gas separation membrane while the gaseous mixture being kept in contact with a surface on one side of the gas separation membrane at a temperature of 70.degree. C. or higher to obtain a gaseous mixture comprising the organic compound vapor and a reduced amount of a water vapor.

Method for dehydration and concentration of aqueous solution containing

An electrolytic capacitor which can be protected from rupture thereof due to an increased pressure of electrolytically generated hydrogen gas therein and can be continuously used over a long period of time, comprises an electrolytic liquid contained in a closed container, at least one pair of an anode foil and a cathode foil immersed in the electrolytic liquid, alternately superimposed on each other, coiled together and spaced apart by at least one insulating spacer to form an electrolytic capacitor, anode and cathode terminals being respectively connected to the anode and cathode foils and extending to the outside of the container, and a semipermeable membrane element arranged in a portion of the container and having at least one semipermeable membrane which exhibits, a hydrogen gas-permeating rate of 3.6 cm.sup.3 /cm.sup.2 .multidot.1000 hours or more determined at 50.degree. C. under a hydrogen gas partial pressure of 2 kg/cm.sup.2 and a water vapor-permeating rate of 2000 cm.sup.3 /cm.sup.2 .multidot.1000 hours or less determined at 50.degree. C. under a water vapor partial pressure of 1 kg/cm.sup.2 or less, to allow the permeation of hydrogen gas therethrough but not the permeation of the electrolytic liquid.

Electrolytic capacitor

A water vapor-containing gas is separated to a fraction thereof having an increased content of water vapor and a remaining fraction thereof having a decreased content of water vapor by a gas separating device which has at least one gas separating membrane having gas feed and delivery surfaces and a ratio P.sub.H.sbsb.2.sub.O /P.sub.CH.sbsb.4 of water vapor-permeating rate P.sub.H.sbsb.2.sub.O to methane gas permeating rate P.sub.CH.sbsb.4 of 200 or more, and preferably, made by an aromatic imide polymer, in such a manner that (1) a water vapor-containing feed gas is fed to a feed side of the gas separating device; (2) the feed gas is flowed along the gas feed surface of the gas separating membrane to allow a fraction of the feed gas to permeate through the gas separating membrane; (3) a drying gas containing 300 ppm or less of water vapor is fed to a delivery side of the gas separating device; (4) the fed drying gas is flowed along the delivery surface of the gas separating membrane to promote the permeation of water vapor through the gas separating membrane; (5) the permeated gas fraction is collected together with the flowed drying gas at the delivery side of the gas separating device; and (6) a remaining gas fraction not permeated through the gas separating membrane and having a decreased content of water vapor is recovered from the feed side of the gas separating device.

Method for removing water vapor from water vapor-containing gas

Growing community of inventors

Ichihara, Japan

Kanji Nakagawa