Tosoh Corporation

Toyo Soda Manufacturing Co., Ltd.

Holland Sweetner Company V.o.f.

Tsugio Murakami

Sadakatsu Kumoi

Kengo Okajima

Yoichi Hiraga

Kazushige Igawa

Hidetoshi Wakamatsu

Hiroyuki Saito

Hiroyuki Wakamatsu

Hiroyuki Saitoh

Mitsuo Kikuchi

Osamu Fujii

Taizo Kawamoto

Masaru Sakuma

Nobuyuki Gotoh

Hidetaka Egashira

Koichi Ohashi

Manabu Sakurai

Kouya Honjoh

Yoshio Abe

To provide a process for recovering high quality hydrogen chloride rationally with good economical efficiency, particularly hydrogen chloride with an elevated quality level to be provided as the feedstock for the oxychlorination reaction in producing dichloroethane and a vinyl chloride monomer from a hydrogen chloride gas to be generated by the combustion of chlorine based waste. To use a process for recovering hydrogen chloride from chlorine based waste comprises adding water and a reducing agent to an acid gas obtained by the combustion of chlorine based waste to effect reaction to obtain a crude hydrogen chloride aqueous solution having an oxidation-reduction potential of not higher than 900 mV and then, distilling the crude hydrogen chloride aqueous solution to obtain a purified hydrogen chloride gas.

Method for recovering hydrogen chloride from chlorine based waste and use of recovered hydrogen chloride

An economical, industrial and ecologically-sound process for producing high test hypochlorite and a calcium chloride aqueous solution comprising the steps of (a) preparing milk of lime, (b) chlorinating the milk of lime to crystallize calcium hypochlorite dihydrate in the presence of the prismatic calcium hypochlorite dihydrate seed crystals having a specific habit to prepare a slurry of coarse calcium hypochlorite dihydrate crystals, (c) separating the slurry into a wet cake of calcium hypochlorite dihydrate crystals and a mother liquor containing calcium hypochlorite and calcium chloride, (d) drying the wet cake to provide high test hypochlorite, and (e) adding hydrochloric acid to the mother liquor or bringing the mother liquor into contact with an oxide of at least one of Mn, Fe, Co, Ni, Cu, and Pd to decompose the calcium hypochlorite to obtain a calcium chloride aqueous solution.

Process for producing high test hypochlorite and calcium chloride aqueous solution

An ion-exchanger is provided which comprises zirconium hydroxide supported on active carbon. The process for producing the ion-exchanger, and a process for removing a multiply charged anion are also provided which employ the ion-exchanger. The ion-exchanger of the present invention has high chemical resistance, high heat resistance, high mechanical strength, and excellent ion exchange characteristics.

Ion-exchanger, process for production thereof, and process for removal

Described herein is a method for crystallizing aspartame (APM) by cooling an aqueous solution containing APM without forced convection during part of the crystallization, wherein a clear aqueous APM solution is initially cooled under forced convection and forced convection is interrupted, after crystallization has started but before the concentration of the APM crystals formed in the system reaches 0.5% by weight, until the amount of crystals reaches at least 10%, but not more than 50%, of the target amount, and wherein cooling is interrupted for at least part of the time of said interruption of forced convection at about the same time or shortly thereafter.

Method for crystallizing .alpha.-L-aspartyl-L-phenylalanine methyl ester

An oxidizable substance and/or a reducible substance is removed from a liquid, such as a liquid industrial waste, by treating the liquid with a composite comprising a fluorine-containing organic cation exchanger and a metal oxide or hydroxide, supported on the cation exchanger. The metal of the metal oxide or hydroxide is selected from manganese and elements of group 1B and group 8 of the periodic table. This treatment is carried out, if required, in the presence of an oxidizing agent, or by using the composite which has previously been treated with an oxidizing agent.

Process for removing oxidizable substance or reducible substance,

The invention relates to processes for removing chlorate salts from an aqueous alkali chloride solution employed in cation-exchange membrane electrolysis, comprising the steps of adding hydrochloric acid to an aqueous alkali chloride solution to form a reaction solution, and maintaining the absolute pressure of the reaction solution at a range not higher than 600 mmHg and not lower than the saturated vapor pressure of the solution in a decomposition vessel and/or feeding the reaction solution to the bottom portion of a decomposition vessel and causing the reaction solution to flow upward in the decomposition vessel.

Process for removing chlorate salt from aqueous alkali chloride solution

A granular calcium hypochlorite composition comprising a particle of calcium hypochlorite dihydrate and/or calcium hypochlorite anhydride, the surface of which has been covered with a double decomposition product of calcium hypochlorite and an alkali metal hydroxide. This composition is prepared by adhering an aqueous alkali metal hydroxide solution to the particle of calcium hypochlorite dihydride or calcium hypochlorite anhydride, and the drying the particle.

Granular calcuim hypochlorite composition and process for preparation

Disclosed is a granular calcium hypochlorite composition having a calcium hypochlorite content of at least 55 wt. % and composed of particles having an ellipsoidal shape in section, wherein at least 50 wt. % of the ellipsoidal particles have a short diameter of 0.3-5 mm, a long diameter of 0.5-20 mm, and a long diameter/short diameter ratio larger than 1.5 but not larger than 5. This composition is prepared by a process wherein a wet calcium hypochlorite composition comprising at least 40 wt. % of calcium hypochlorite and 25-45 wt.% of water is extruded through a die having an orifice diameter of 0.3-5 mm; the extrudate is cut to a length of 0.5-20 mm so that the length/orifice diameter ratio is larger than 1.5 but not larger than 5 to form columnar shaped particles; the columnar shaped particles are subjected to rolling granulation; and the resulting granules are dried until the water content is reduced to 4-22 wt. %.

Calcium hypochlorite composition and process for preparation thereof

Ethyleneamines are recovered from an aqueous solution of carbonates of ethyleneamines by distilling an aqueous solution of carbonates of ethyleneamines including ethylenediamine, in which the molar ratio of the carbon dioxide component to the ethyleneamines including ethylenediamine is 0.01 to 0.5, whereby ethylenediamine is distilled out together with water. The aqueous solution to be distilled is advantageously prepared by heating an aqueous solution of carbonates of ethyleneamines including ethylenediamine to effect decarboxylation.

Process for recovering ethyleneamines from aqueous solution of

Ethyleneamines are efficiently recovered from an aqueous solution thereof by extracting them from the aqueous solution into an organic phase with an extractant selected from carbonyl group-containing organic solvents, benzyl alcohol, carboxylic acids and salts thereof, alkylphosphoric acids and salts thereof, and mixed solvents containing at least one of these extractants. The ethyleneamines in the organic phase is recovered preferably from the organic phase to the aqueous phase by incorporating an acid therein, followed by phase separation.

Process for recovering ethyleneamines

A stable calcium hypochlorite composition and a method for the preparation thereof. The composition has a calcium hypochlorite anhydride and/or a calcium hypochlorite dihydrate used as main constituent and comprises at least 60 wt % of calcium hypochlorite; at least 5 wt % of calcium hydroxide; at least 4 wt % of water content; and 5 wt % or less of than that calcium chloride. The composition is stable and decomposes only in a less degree at a high temperature and during storage over a long period.

Stable calcium hypochlorite composition and method for manufacture

A dihydrate of calcium hypochlorite of a prismatic crystal shape in which the lengths of axes a, b and c thereof are in the ratios satisfying the following formulas (1), (2) and (3):

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Shinnanyo, Japan

Tsugio Murakami