This Communication describes the hydrogenation of carbon dioxide to methanol via tandem catalysis with dimethylamine and a homogeneous ruthenium complex. Unlike previous examples with homogeneous catalysts, this CO2-to-CH3OH process proceeds under basic reaction conditions. The dimethylamine is proposed to play a dual role in this system. It reacts directly with CO2 to produce dimethylammonium dimethylcarbamate, and it also intercepts the intermediate formic acid to generate dimethylformamide. With the appropriate selection of catalyst and reaction conditions, >95% conversion of CO2 was achieved to form a mixture of CH3OH and dimethylformamide.

Tandem amine and ruthenium-catalyzed hydrogenation of CO2 to methanol.

This review focuses on important stability issues facing amine-functionalized CO2 adsorbents, including amine-grafted and amine-impregnated silicas, zeolites, metal–organic frameworks and carbons. During the past couple of decades, major advances were achieved in understanding and improving the performance of such materials, particularly in terms of CO2 adsorptive properties such as adsorption capacity, selectivity and kinetics. Nonetheless, to pave the way toward commercialization of adsorption-based CO2 capture technologies, in addition to other attributes, adsorbent materials should be stable over many thousands of adsorption–desorption cycles. Adsorbent stability, which is of utmost importance as it determines adsorbent lifetime and operational costs of CO2 capture, is a multifaceted issue involving thermal, hydrothermal, and chemical stability. Here we discuss the impact of the adsorbent physical and chemical properties, the feed gas composition and characteristics, and the adsorption–desorption operational parameters on the long-term stability of amine-functionalized CO2 adsorbents. We also review important insights associated with the underlying deactivation pathways of the adsorbents upon exposure to high temperature, oxygen, dry CO2, sulfur-containing compounds, nitrogen oxides, oxygen and steam. Finally, specific recommendations are provided to address outstanding stability issues.

Stability of amine-functionalized CO2 adsorbents: a multifaceted puzzle.

A comparative review between amines and ammonia as sorptive media for post-combustion CO2 capture

A CO2 recovery apparatus according to a first embodiment of the present invention includes: a CO2 absorber that brings flue gas containing CO2 into contact with CO2 absorbing liquid to reduce CO2 in the flue gas; a regenerator that reduces CO2 in CO2 absorbing liquid (rich solvent) that has absorbed the CO2 in the CO2 absorber to regenerate the CO2 absorbing liquid, so that the regenerated absorbing liquid (lean solvent), having CO2 reduced in the regenerator, is reused in the CO2 absorber; a first compressor to a fourth compressor that compress the CO2 gas released from the regenerator; and an O2 reducing apparatus arranged between the second compressor and a second cooler to reduce O2 in the CO2 gas.

Co2 recovery apparatus and co2 recovery method

Evaluation of a phase change solvent for CO2 capture: Absorption and desorption tests

PROBLEM TO BE SOLVED: To provide a CO 2 recovery apparatus and a recovery method with improved energy efficiency. SOLUTION: The CO 2 recovery apparatus has a CO 2 absorption tower where flue gas containing CO 2 is brought into contact with a CO 2 absorption liquid to remove CO 2 from the flue gas, and a regeneration tower where CO 2 is removed from the rich solution which is the CO 2 absorption liquid with CO 2 absorbed therein to regenerate a lean solution which is a CO 2 absorption liquid without absorption of CO 2 , so as to reuse the lean solution from which CO 2 is removed in the regeneration tower again in the absorption tower; wherein the apparatus is provided with a flow passage for extracting a semi-lean solution, temperature rising and returning, so as to extract at least a part of the semi-lean solution prepared by allowing a part of CO 2 to emit from the rich solution injected into the regeneration tower from the upper part of the regeneration tower, from the regeneration tower, to elevate the temperature of the solution by heat exchange with a high temperature flue gas in a flue of an industrial equipment such as a boiler and a gas turbine, and to return the solution to the regeneration tower at a position lower than the semi-lean solution extraction position of the tower. COPYRIGHT: (C)2006,JPO&NCIPI

Co2 recovery apparatus and method

A CO2 recovering apparatus includes: a CO2 absorber that brings flue gas containing CO2 into contact with CO2 absorbent to reduce the CO2 contained in the flue gas; a regenerator that reduces CO2 contained in rich solvent that has absorbed CO2 in the CO2 absorber to regenerate the rich solvent, so that the CO2 absorbent that is lean solvent having CO2 reduced in the regenerator is reused in the CO2 absorber; and a controller that controls to detect the absorbent concentration in the CO2 absorbent, to increase the volume of CO2 absorbent to be circulated based on a decrease in the absorbent concentration, and to adjust the volume of steam to be supplied in the regenerator based on the volume of the CO2 absorbent to be circulated.

CO2 recovering apparatus and method

Result of the 60 tpd CO2 capture pilot plant in European coal power plant with KS-1TM solvent

A CO 2 recovering apparatus includes: a CO 2 absorber (16) that brings flue gas containing CO 2 into contact with CO 2 absorbent to reduce the CO 2 contained in the flue gas; a regenerator (18) that reduces CO 2 contained in rich solvent that has absorbed CO 2 in the CO 2 absorber (16) to regenerate the rich solvent, so that the CO 2 absorbent that is lean solvent having CO 2 reduced in the regenerator (18) is reused in the CO 2 absorber (16); and a controller that controls to detect the absorbent concentration in the CO 2 absorbent, to increase the volume of CO 2 absorbent to be circulated based on a decrease in the absorbent concentration, and to adjust the volume of steam to be supplied in the regenerator (18) based on the volume of the CO 2 absorbent to be circulated.

CO2 recovering method

A carbon dioxide recovery unit is provided with: an absorption tower for bringing an exhaust gas into contact with a CO 2 absorbing liquid to thereby absorb and recover CO 2 from the exhaust gas; a regeneration tower for taking out the CO 2 from the CO 2 absorbing liquid; a CO 2 delivery line L 3 for delivering the taken-out CO 2 to a storage process; and a CO 2 return line L 5 for returning the taken-out CO 2 to the absorption tower. When a CO 2 recovery unit and a CO 2 compressing device are activated, if a storage process side has some kind of trouble and cannot receive the CO 2 , a destination part to which the CO 2 is delivered from the regeneration tower is switched from the CO 2 delivery line L 3 to the CO 2 return line L 5 , whereby the CO 2 gas is mixed with the exhaust gas in the absorption tower.

Yoshiki Sorimachi

Papers

Co2 recovery apparatus and method

CO2 recovering apparatus and method

Result of the 60 tpd CO2 capture pilot plant in European coal power plant with KS-1TM solvent

CO2 recovering method

Carbon dioxide recovery device