1094results about "By absorption" patented technology

Processes and apparatuses are described for the selective removal and recovery of acid gases from a gas source comprising at least hydrogen sulfide and carbon dioxide. A step-wise approach is illustrated wherein hydrogen sulfide may be selectively removed from a gas source by treatment with methanol under conditions where substantially all the hydrogen sulfide may be removed. The partially purified gas source may then be provided with a second treatment with methanol under conditions which selectively remove carbon dioxide from the gas stream. Such methods are generally applicable to any gas source comprising at least hydrogen sulfide and carbon dioxide, for example, a gas source produced from the catalytic gasification of a carbonaceous material, the combustion of a carbonaceous material, or the oxy-blown gasification of a carbonaceous material.

Compositions comprising synthetic rock, e.g., aggregate, and methods of producing and using them are provided. The rock, e.g., aggregate, contains CO2 and / or other components of an industrial waste stream. The CO2 may be in the form of divalent cation carbonates, e.g., magnesium and calcium carbonates. Aspects of the invention include contacting a CO2 containing gaseous stream with a water to dissolve CO2, and placing the water under precipitation conditions sufficient to produce a carbonate containing precipitate product, e.g., a divalent cation carbonate.

A reaction-based process has been developed for the selective removal of carbon dioxide (CO2) from a multicomponent gas mixture to provide a gaseous stream depleted in CO2 compared to the inlet CO2 concentration in the stream. The proposed process effects the separation of CO2 from a mixture of gases (such as flue gas / fuel gas) by its reaction with metal oxides (such as calcium oxide). The Calcium based Reaction Separation for CO2 (CaRS—CO2) process consists of contacting a CO2 laden gas with calcium oxide (CaO) in a reactor such that CaO captures the CO2 by the formation of calcium carbonate (CaCOa). Once “spent”, CaCO3 is regenerated by its calcination leading to the formation of fresh CaO sorbent and the evolution of a concentrated stream of CO2. The “regenerated” CaO is then recycled for the further capture of more CO2. This carbonation-calcination cycle forms the basis of the CaRS—CO2 process. This process also identifies the application of a mesoporous CaCO3 structure, developed by a process detailed elsewhere, that attains >90% conversion over multiple carbonation and calcination cycles. Lastly, thermal regeneration (calcination) under vacuum provided a better sorbent structure that maintained reproducible reactivity levels over multiple cycles.

Methods are provided for the selective removal of CO2 from a multicomponent gaseous stream to provide a CO2 depleted gaseous stream. In practicing the subject methods, an initial multicomponent gaseous stream is contacted with an aqueous fluid under conditions of selective CO2 clathrate formation to produce a CO2 clathrate slurry and CO2 depleted gaseous stream. A feature of the subject methods is that the CO2 clathrate slurry is then compressed to high pressure to produce a high-pressure CO2 product. Also provided are systems that find use in practicing the subject methods. The subject methods and systems find use in a variety of applications where it is desired to selectively remove CO2 from a multicomponent gaseous stream.

Methods of sequestering carbon dioxide (CO2) are provided. Aspects of the methods include precipitating a storage stable carbon dioxide sequestering product from an alkaline-earth-metal-containing water and then disposing of the product, e.g., by placing the product in a disposal location or using the product as a component of a manufactured composition. Also provided are systems for practicing methods of the invention.

One aspect of the present invention relates to ionic liquids comprising a pendant Bronsted-acidic group, e.g., a sulfonic acid group. Another aspect of the present invention relates to the use of an ionic liquid comprising a pendant Bronsted-acidic group to catalyze a Bronsted-acid-catalyzed chemical reaction. A third aspect of the present invention relates to ionic liquids comprising a pendant nucleophilic group, e.g., an amine. Still another aspect of the present invention relates to the use of an ionic liquid comprising a pendant nucleophilic group to catalyze a nucleophile-assisted chemical reaction. A fifth aspect of the present invention relates to the use of an ionic liquid comprising a pendant nucleophilic group to remove a gaseous impurity, e.g., carbon dioxide, from a gas, e.g., sour natural gas.

Methods of sequestering carbon dioxide (CO2) are provided. Aspects of the methods include precipitating a storage stable carbon dioxide sequestering product from an alkaline-earth-metal-containing water and then disposing of the product, e.g., by placing the product in a disposal location or using the product as a component of a manufactured composition. Also provided are systems for practicing methods of the invention.

Power plants and process for lowering CO2 emissions generally includes extracting a portion of the recirculated CO2-rich flue gas mid-way through the compression pathway of a gas turbine and removing the CO2 in a separation unit. The remaining portion of the CO2 rich flue gas (i.e., the portion of the recirculated flue gas that was not fed to the separation unit) is mixed with fresh air coming from an additional compressor-expander and then fed back to the compression pathway. As a result, flue gas recirculation increases the CO2 concentration within the working fluid, leading to an additional increase in CO2 partial pressure. As the concentration and partial pressure of CO2 is increased, a lower energy penalty is observed to remove the CO2. Moreover, a reduced volume is fed to the CO2 separation unit during operation. Consequently, the size of the separation equipment can be reduced as well as the energy required for the separation process.