The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO.sub.2), nitric oxide (NO), nitrogen dioxide (NO.sub.2) (collectively NOR, where x=1, 2) and sulfur dioxide (SO.sub.2) using closed loop technology. The methods recycle process reagents and mass balance consumable reagents that can be made using electrochemical separation of sodium chloride (NaCl) or potassium chloride (KCl). The technology applies to marine and terrestrial exhaust gas sources for CO.sub.2, NOx and SO.sub.2. The integrated technology combines compatible and green processes that capture and/or convert CO.sub.2, NOx and SO.sub.2 into compounds that enhance the environment, many with commercial value.

A treatment method for reducing carbon dioxide emission of combustion exhaust gas includes: a caustic soda synthesis step; a treatment step of reducing carbon dioxide emission of combustion exhaust gas; and a recycling step. In the caustic soda synthesis step, a natural sodium carbonate aqueous solution (Na.sub.2CO.sub.3) prepared by dissolving natural sodium carbonate ore powder composed of Na.sub.2CO.sub.3 and NaHCO.sub.3 in a caustic soda aqueous solution is used to generate a caustic soda aqueous solution and calcium carbonate precipitate by a causticization reaction with slaked lime, and solid-liquid separation is performed to obtain a synthetic caustic soda aqueous solution. In the treatment step, the synthetic caustic soda aqueous solution and purified combustion exhaust gas are brought into gas-liquid countercurrent contact so that carbon dioxide in the exhaust gas is absorbed by the synthetic caustic soda aqueous solution and immobilized as sodium carbonate.

A treatment method for reducing carbon dioxide emission of combustion exhaust gas includes: a caustic soda synthesis step; a treatment step of reducing carbon dioxide emission of combustion exhaust gas; and a recycling step. In the caustic soda synthesis step, a natural sodium carbonate aqueous solution (Na.sub.2CO.sub.3) prepared by dissolving natural sodium carbonate ore powder composed of Na.sub.2CO.sub.3 and NaHCO.sub.3 in a caustic soda aqueous solution is used to generate a caustic soda aqueous solution and calcium carbonate precipitate by a causticization reaction with slaked lime, and solid-liquid separation is performed to obtain a synthetic caustic soda aqueous solution. In the treatment step, the synthetic caustic soda aqueous solution and purified combustion exhaust gas are brought into gas-liquid countercurrent contact so that carbon dioxide in the exhaust gas is absorbed by the synthetic caustic soda aqueous solution and immobilized as sodium carbonate.

The present disclosure relates to a method for chemically modifying particles of a bicarbonate salt in a co-rotating twin-screw extruder and chemically modified bicarbonate particles prepared therefrom. The present disclosure also relates to a method for controlling an amount of carbonate salt formed during chemical modification of bicarbonate salt particles.

The present disclosure relates to a method for chemically modifying particles of a bicarbonate salt in a co-rotating twin-screw extruder and chemically modified bicarbonate particles prepared therefrom. The present disclosure also relates to a method for controlling an amount of carbonate salt formed during chemical modification of bicarbonate salt particles.

The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO.sub.2), nitric oxide (NO), nitrogen dioxide (NO.sub.2) (collectively NO.sub.x, where x=1, 2) and sulfur dioxide (SO.sub.2) using closed loop technology. The methods recycle process reagents and mass balance consumable reagents that can be made using electrochemical separation of sodium chloride (NaCl) or potassium chloride (KCl). The technology applies to marine and terrestrial exhaust gas sources for CO.sub.2, NOx and SO.sub.2. The integrated technology combines compatible and green processes that capture and/or convert CO.sub.2, NOx and SO.sub.2 into compounds that enhance the environment, many with commercial value.

The present invention relates to a method for the production of sodium bicarbonate, particularly for producing sodium bicarbonate on an industrial scale, the method comprising the steps of: a. treating a carbonaceous feedstock to form a product stream comprising up to 10 v/v % carbon dioxide; b. capturing at least a portion of the carbon dioxide from the product stream to form a carbon dioxide stream; c. feeding the carbon dioxide stream to a reaction vessel; d. feeding an aqueous sodium carbonate solution to the reaction vessel; e. contacting at least a portion of the carbon dioxide stream with at least a portion of the aqueous sodium carbonate solution to form a slurry comprising solid sodium bicarbonate; and f. separating the solid component of the slurry from the liquid component of the slurry to provide solid sodium bicarbonate and an aqueous liquor.

The present invention relates to a method for the production of sodium bicarbonate, particularly for producing sodium bicarbonate on an industrial scale, the method comprising the steps of: a. treating a carbonaceous feedstock to form a product stream comprising up to 10 v/v % carbon dioxide; b. capturing at least a portion of the carbon dioxide from the product stream to form a carbon dioxide stream; c. feeding the carbon dioxide stream to a reaction vessel; d. feeding an aqueous sodium carbonate solution to the reaction vessel; e. contacting at least a portion of the carbon dioxide stream with at least a portion of the aqueous sodium carbonate solution to form a slurry comprising solid sodium bicarbonate; and f. separating the solid component of the slurry from the liquid component of the slurry to provide solid sodium bicarbonate and an aqueous liquor.

A method includes: (1) using a chelating agent, extracting divalent ions from a brine solution as complexes of the chelating agent and the divalent ions; (2) using a weak acid, regenerating the chelating agent and producing a divalent ion salt solution; and (3) introducing carbon dioxide to the divalent ion salt solution to induce precipitation of the divalent ions as a carbonate salt. Another method includes: (1) combining water with carbon dioxide to produce a carbon dioxide solution; (2) introducing an ion exchanger to the carbon dioxide solution to induce exchange of alkali metal cations included in the ion exchanger with protons included in the carbon dioxide solution and to produce a bicarbonate salt solution of the alkali metal cations; and (3) introducing a brine solution to the bicarbonate salt solution to induce precipitation of divalent ions from the brine solution as a carbonate salt.

A method includes: (1) using a chelating agent, extracting divalent ions from a brine solution as complexes of the chelating agent and the divalent ions; (2) using a weak acid, regenerating the chelating agent and producing a divalent ion salt solution; and (3) introducing carbon dioxide to the divalent ion salt solution to induce precipitation of the divalent ions as a carbonate salt. Another method includes: (1) combining water with carbon dioxide to produce a carbon dioxide solution; (2) introducing an ion exchanger to the carbon dioxide solution to induce exchange of alkali metal cations included in the ion exchanger with protons included in the carbon dioxide solution and to produce a bicarbonate salt solution of the alkali metal cations; and (3) introducing a brine solution to the bicarbonate salt solution to induce precipitation of divalent ions from the brine solution as a carbonate salt.