Method of concentrating aqueous alkali and apparatus suitable for this purpose. A very energy-saving method of concentrating aqueous alkali originating, for example, from a chloralkali electrolysis plant and an apparatus suitable for this purpose are described. The method/the apparatus utilizes heat of reaction from the formation of 1,2-dichloroethane and includes multistage concentration of the aqueous alkali, where at least part of the heat required for concentrating the aqueous alkali originates from the plant for preparing 1,2-dichloroethane and at least a further part of the heat required for concentrating the aqueous alkali originates from at least one of the higher stages of the plant for concentrating the aqueous alkali and is used for partial heating of the first stage. The apparatus can be used for retrofitting existing integrated plants made up of a DCE plant and chloralkali electrolysis or in the erection of new plants.

Method of concentrating aqueous alkali and apparatus suitable for this purpose. A very energy-saving method of concentrating aqueous alkali originating, for example, from a chloralkali electrolysis plant and an apparatus suitable for this purpose are described. The method/the apparatus utilizes heat of reaction from the formation of 1,2-dichloroethane and includes multistage concentration of the aqueous alkali, where at least part of the heat required for concentrating the aqueous alkali originates from the plant for preparing 1,2-dichloroethane and at least a further part of the heat required for concentrating the aqueous alkali originates from at least one of the higher stages of the plant for concentrating the aqueous alkali and is used for partial heating of the first stage. The apparatus can be used for retrofitting existing integrated plants made up of a DCE plant and chloralkali electrolysis or in the erection of new plants.

Method of concentrating aqueous alkali and apparatus suitable for this purpose. A very energy-saving method of concentrating aqueous alkali originating, for example, from a chloralkali electrolysis plant and an apparatus suitable for this purpose are described. The method/the apparatus utilizes heat of reaction from the formation of 1,2-dichloroethane and includes multistage concentration of the aqueous alkali, where at least part of the heat required for concentrating the aqueous alkali originates from the plant for preparing 1,2-dichloroethane and at least a further part of the heat required for concentrating the aqueous alkali originates from at least one of the higher stages of the plant for concentrating the aqueous alkali and is used for partial heating of the first stage. The apparatus can be used for retrofitting existing integrated plants made up of a DCE plant and chloralkali electrolysis or in the erection of new plants.

The present application provides, among other things, compounds and methods for metathesis reactions. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and/or stereoselectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and Z-selectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and E-selectivity. In some embodiments, provided technologies are particularly useful for preparing alkenyl fluorides. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-a. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-b.

The present application provides, among other things, compounds and methods for metathesis reactions. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and/or stereoselectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and Z-selectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and E-selectivity. In some embodiments, provided technologies are particularly useful for preparing alkenyl fluorides. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-a. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-b.

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with an unsaturated hydrocarbon and/or a saturated hydrocarbon to form products. Separation and/or purification of the products as well as of the metal ions in the lower oxidation state and the higher oxidation state, is provided herein.

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with an unsaturated hydrocarbon and/or a saturated hydrocarbon to form products. Separation and/or purification of the products as well as of the metal ions in the lower oxidation state and the higher oxidation state, is provided herein.

There are provided methods and systems for an electrochemical cell including an anode and a cathode where the anode is contacted with a metal ion that converts the metal ion from a lower oxidation state to a higher oxidation state. The metal ion in the higher oxidation state is reacted with an unsaturated hydrocarbon and/or a saturated hydrocarbon to form products. Separation and/or purification of the products as well as of the metal ions in the lower oxidation state and the higher oxidation state, is provided herein.

An object of the present invention is to provide a method for producing a fluorinated organic compound, whereby an iodosylbenzene derivative can be easily separated and recovered. The above object can be achieved by a method for producing a fluorinated organic compound, comprising step A of fluorinating an organic compound (1) by reaction with a fluorine source (3) in the presence of a hypervalent iodine aromatic ring compound (2a), or in the presence of an iodine aromatic ring compound (2b) and an oxidant (2bo); wherein the fluorine source (3) is a fluorine source (3a) represented by formula: MF.sub.n, wherein M is H, a metal of Group 1 of the periodic table, or a metal of Group 2 of the periodic table; and n is 1 or 2; and step B of separating the iodine aromatic ring compound from a reaction liquid after step A is started.

An object of the present invention is to provide a method for producing a fluorinated organic compound, whereby an iodosylbenzene derivative can be easily separated and recovered. The above object can be achieved by a method for producing a fluorinated organic compound, comprising step A of fluorinating an organic compound (1) by reaction with a fluorine source (3) in the presence of a hypervalent iodine aromatic ring compound (2a), or in the presence of an iodine aromatic ring compound (2b) and an oxidant (2bo); wherein the fluorine source (3) is a fluorine source (3a) represented by formula: MF.sub.n, wherein M is H, a metal of Group 1 of the periodic table, or a metal of Group 2 of the periodic table; and n is 1 or 2; and step B of separating the iodine aromatic ring compound from a reaction liquid after step A is started.