The heat transfer characteristics and energy consumption of CO₂ desorption from rich N-methyldiethanolamine solution were evaluated in a highly efficient microchannel reactor. Nucleate boiling was determined as the dominant heat transfer mechanism. The heat transfer coefficients were larger than those reported for CO₂ desorption. A correlation was proposed to predict the heat transfer coefficient.

Adsorbents combining a small amount of ionic liquids (ILs) and a large amount of porous solid supports like silica were designed as good alternatives for conventional CO₂ capture solvents. Silica-supported ILs were synthesized by impregnation-vaporization. Impregnation of ILs onto the silica support improved the CO₂ sorption capacity significantly. CO₂-saturated sorbents can be easily recycled.

A sorbent modeling technology was applied to produce spherically shaped sorbents with enhanced anti-attrition property for the industrial calcium looping process and glucose was templated to ameliorate the porous structure of calcium-based sorbents. An excellent anti-attrition performance compared to limestone and an improved CO₂ capture performance of the templated sorbents could be achieved.

The state-of-the art membrane developments, especially for CO₂ separation via the two membrane technologies, namely, membrane gas separation and membrane contactor, are updated. Concepts, challenges, and strategies to tackle the limitations of both membrane technologies are discussed. Future perspectives of these technologies as a potential solution for CO₂ removal and utilization are discussed.

Gas-liquid hollow-fiber membrane contactors are favorable alternatives to conventional absorption techniques for CO₂ capture. For removal of CO₂ from a N₂/CO₂ gas mixture, α-Al₂O₃/water and γ-Al₂O₃/water nanofluids were applied in a dialysis nanoporous hollow-fiber membrane contactor. The nanofluids enhanced significantly the mass transfer coefficients and absorption rates of CO₂.

Chemical looping combustion (CLC) is a potentially economic technology allowing for high fuel combustion efficiency with inherent separation of pure CO₂. The CLC-combined cycle with coke oven gas as fuel and NiO/NiAl₂O₄ as an oxygen carrier exhibits high system efficiency with a CO₂ capture efficiency of almost 100 % and near-zero carbon emission.

Hollow-fiber mixed-matrix membranes (HFMMMs) possess great potential for CO₂ separation. Different inorganic fillers can be incorporated into various types of polymeric materials for fabrication of HFMMMs. Current trends, updated performances, issues on fabrication, and applicable models for prediction of transport properties of HFMMMs in CO₂/N₂ and CO₂/CH₄ separation are reviewed in detail.

The heat of CO₂ absorption is a key factor governing the operating cost of the CO₂ absorption process when using aqueous amine solutions. Piperidine derivatives were tested in order to identify the effect of the functional groups on CO₂ loading and heat of absorption. The introduction of functional groups could be advantageous in CO₂ absorption and stripping performance.

For clean energy production, gasification offers the best combination of investment and value of produced electricity compared to other methods. A parametric study of co-gasification of biomass and coal in a circulation fluidized-bed gasification system was performed using an Aspen Plus simulator. Particular focus was lying on the hydrogen and tar yields obtained by this technology.

A one-step process for generation of NaOH via electrolysis of NaCl and CO₂ absorption simultaneously in an electrochemical device allows reducing the capital cost in the entire process for carbonate mineral production. The simultaneous process was performed in an electrolyzer and produced aqueous carbonate/bicarbonate solutions prior to the mineralization process.

Reducing the amount of industrially emitted CO₂ is increasingly important because of global warming. This study investigates calcium oxide as a CO₂ adsorbent in fluidized-bed systems. CaO can be generated from the decomposition of calcium carbonate, which is abundant throughout nature. Using such natural calcium-based materials can help reduce agricultural waste and support ecofriendly materials.

The growth of algae requires CO₂ as one of the main nutrients, so there is an opportunity to sequester CO₂ by using flue gas emissions from industrial sources as the feed for algae cultivation. A microalgae culture recycle solution was successfully reused to capture CO₂ in a continuous bubble-column scrubber under a constant pH environment. Optimum conditions were elaborated.

Chemical absorption is an attractive technology for CO₂ capture. Among different chemical absorbents suggested for this application, ionic liquids containing amino acids as anions are promising candidates for industrial implementation. A fast and effective method with low energy requirement in terms of microwave-assisted regeneration of the absorbents from the CO₂-saturated solution is proposed.

Commonly applied inert solid supports are considered effective to improve the CO₂ capture performance of CaO sorbents, but stem from expensive raw materials. Cheap waste sludge from steel plants is premixed with natural limestone and fed into a calcium looping system. Thereby, both the enhanced CO₂ capture performance of limestone and the reuse of the waste industrial sludge could be implemented.

Increasing levels of CO₂ emissions from natural gas streams and burned fossil fuels are a serious environmental concern. Therefore, removal of CO₂ is necessary. A kinetic investigation of CO₂ adsorption/desorption has been carried out on sorbents with and without surfactants. Unlike most of the previous kinetic treatments reported, the present model aims to specifically distinguish between surface and bulk adsorption processes.