A method of treating a metal carbonate salt includes hydrolyzing a metal halide salt to form a hydrohalic acid and a hydroxide salt of the metal in the metal halide salt. The metal includes an alkaline earth metal or an alkali metal. The method includes reacting the hydrohalic acid with the metal carbonate salt, wherein the metal carbonate salt is a carbonate salt of the alkaline earth metal or alkali metal, to form CO.sub.2 and the metal halide salt. At least some of the metal halide salt formed from the reacting of the hydrohalic acid with the metal carbonate salt is recycled as at least some of the metal halide salt in the hydrolyzing of the metal halide salt to form the hydrohalic acid and the hydroxide salt.

A method of treating a metal carbonate salt includes hydrolyzing a metal halide salt to form a hydrohalic acid and a hydroxide salt of the metal in the metal halide salt. The metal includes an alkaline earth metal or an alkali metal. The method includes reacting the hydrohalic acid with the metal carbonate salt, wherein the metal carbonate salt is a carbonate salt of the alkaline earth metal or alkali metal, to form CO.sub.2 and the metal halide salt. At least some of the metal halide salt formed from the reacting of the hydrohalic acid with the metal carbonate salt is recycled as at least some of the metal halide salt in the hydrolyzing of the metal halide salt to form the hydrohalic acid and the hydroxide salt.

Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydroxychloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.

The invention relates to a process and its relating plant for thermal conversion of aluminum chloride hydrate into aluminum oxide and gaseous hydrogen chloride. In a first step, aluminum chloride hydrate is fed into a decomposition reactor where it is heated to a temperature between 120 and 400° C. Afterwards, the partially decomposed aluminum chloride hydrate is finally calcined to aluminum oxide at a temperature between 850 and 1200° C. in a second reactor. The aluminum chloride hydrate is admixed with aluminum oxide in an intensive mixer with a mass ratio between 1:1 and 10:1 aluminum chloride hydrate to aluminum oxide for using a fluidized bed reactor as a decomposition reactor.

Embodiments of the present disclosure are directed to systems and methods of removing carbon dioxide from a gaseous stream using magnesium hydroxide and then regenerating the magnesium hydroxide. In some embodiments, the systems and methods can further comprise using the waste heat from one or more gas streams to provide some or all of the heat needed to drive the reactions. In some embodiments, magnesium chloride is primarily in the form of magnesium chloride dihydrate and is fed to a decomposition reactor to generate magnesium hydroxychloride, which is in turn fed to a second decomposition reactor to generate magnesium hydroxide.

The present invention relates to a process for the separation of strong acid from its salts. In said process, a strong acid salt is reacted with organic weak base (OWB) in the presence of a hydrophilic solvent and CO.sub.2. The cation of the strong acid salt is precipitated to produce a carbonate/bicarbonate salt and the strong acid form a liquid salt with the OWB. The above process is performed in a solution comprising both the strong acid salt and the WBO. In the next step, the strong acid is released from its OWB liquid salt and the OWB is returned to a previous step.

The present invention discloses a method and system for conducting high temperature corrosion tests on metallic alloys without the need for extensive laboratory equipment and attendant safety measures through the use of a two-compartment ampoule where a vestibule connects these two compartments. A pre-selected mixture of salts is placed in one compartment in order to generate a specific partial pressure of halogen gas; and a metallic alloy is placed in the other compartment. The ampoule is then heated to a pre-determined temperature and held at this temperature for a pre-determined time period. A halogen gas of a specific partial pressure is thereby generated from the mixture of salts which comes into contact with the metallic alloy. Because the ampoule creates a sealed environment, the metallic alloy is under constant halogenation during the pre-determined time period. The metallic alloy is removed for examination when the pre-determined time period expires.

A process and its relating plant for thermal conversion of aluminum chloride hydrate into aluminum oxide and gaseous hydrogen chloride. In a first step, aluminum chloride hydrate is fed into a decomposition reactor where it is heated to a temperature between 120 and 400° C. Afterwards, the partially decomposed aluminum chloride hydrate is finally calcined to aluminum oxide at a temperature between 850 and 1200° C. in a second reactor. The aluminum chloride hydrate is admixed with aluminum oxide in an intensive mixer with a mass ratio between 1:1 and 10:1 aluminum chloride hydrate to aluminum oxide for using a fluidized bed reactor as a decomposition reactor.

A method for conversion of magnesium chloride into magnesium oxide and HCl, comprising the steps of providing a magnesium chloride compound to a thermohydrolysis reactor, the reactor being at a temperature of at least 300° C., withdrawing MgO from the thermohydrolysis reactor in solid form, and withdrawing a HCl containing gas stream from the thermohydrolysis reactor, wherein the magnesium chloride compound provided to the thermohydrolysis reactor is a solid magnesium chloride compound which comprises at least 50 wt. % of MgCl.sub.2.4H.sub.2O. The process accordingly is fast and can be operated in a manner which is efficient both as regards apparatus and energy. It can also be integrated in a process for converting a magnesium chloride solution.

To provide an ion exchange membrane for alkali chloride electrolysis which has a low membrane resistance and which is capable of reducing the electrolysis voltage during the alkali chloride electrolysis, while increasing the membrane strength.

An ion exchange membrane 1 for alkali chloride electrolysis wherein a reinforcing material 20 obtained by weaving with reinforcing yarns 22 and sacrificial yarns 24 is embedded in a fluoropolymer having ion exchange groups, the ion exchange membrane 1 comprises elution holes (28) formed by eluting at least a portion of a material of the sacrificial yarns 24, and in a cross section perpendicular to the length direction of the yarns, the total area (S) obtained by adding the cross-sectional area of an elution hole 28 and the cross-sectional area of a sacrificial yarn 24 remaining in the elution hole 28 is from 500 to 1,200 μm.sup.2, and the number (n) of elution holes 28 between adjacent reinforcing yarns 22 is at least 10.