A Review on Carbon Dioxide Minimization in Biogas Upgradation Technology by Chemical Absorption Processes

Abstract

With an ever-increasing population and unpredictable climate changes, meeting energy demands and maintaining a sustainable environment on Earth are two of the greatest challenges of the future. Biogas can be a very significant renewable source of energy that can be used worldwide. However, to make it usable, upgrading the gas by removing the unwanted components is a very crucial step. CO 2 being one of the major unwanted components and also being a major greenhouse gas must be removed efficiently. Different methods such as physical adsorption, cryogenic separation, membrane separation, and chemical absorption have been discussed in detail in this review because of their availability, economic value, and lower environmental footprint. Three chemical absorption methods, including alkanolamines, alkali solvents, and amino acid salt solutions, are discussed. Their primary works with simple chemicals along with the latest works with more complex chemicals and different mechanical processes, such as the DECAB process, are discussed and compared. These discussions provide valuable insights into how different processes vary and how one is more advantageous or disadvantageous than the others. However, the best method is yet to be found with further research. Overall, this review emphasizes the need for biogas upgrading, and it discusses different methods of carbon capture while doing that. Methods discussed here can be a basic foundation for future research in carbon capture and green chemistry. This review will enlighten the readers about scientific and technological challenges regarding carbon dioxide minimization in biogas technology.

Utilization of polyphenylene sulfide as an organic additive to enhance gas separation performance in polysulfone membranes

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Sustainable porous carbons from tannic acid based KOH activated as high-performance CO2 capture sorbents

“…On account of its various benets, including the simplicity of design, a high adsorption capacity, low regeneration energy, and convenient industrial scale-up as well as a good cost economy, the use of a solid adsorbent for CO 2 adsorption represents a promising strategy. [6][7][8][9] Various factors such as the distribution of pore sizes of solid sorbents regulate their capacity for CO 2 adsorption. Micropores, in particular those with #1 nm diameter (classied as narrow micropores), are involved in the adsorption of CO 2 at low pressure (#1 bar), [10][11][12][13] whereas at high pressure (e.g., 30 bar) small mesopores ranging in size from 2-4 nm have a key role in CO 2 uptake.…”

Effect of Reaction Parameters on CO2 Absorption from Biogas Using CaO Sorbent Prepared from Waste Chicken Eggshell

“…Today, scientists worldwide consider carbon capture, storage, and utilization (CCSU) an attractive method for reducing CO 2 emissions. − It involves the capture, compression, transport, geological storage, and use of CO 2 in various ways. Therefore, achievable and cost-effective carbon capture methods are urgently required.…”