Sustainable biomass-based carbon adsorbents for post-combustion CO2 capture

Abstract

Sustainable carbon adsorbents have been produced from biomass residues by single-step activation with CO 2 . The activation conditions were optimised to develop narrow micropores in order to maximise the CO 2 adsorption capacity of the carbons under post-combustion conditions. The equilibrium of adsorption of pure CO 2 and N 2 was measured between 0 and 50 ˚C up to 120 kPa for the outstanding carbons. The CO 2 adsorption capacity measured at low pressures is among the highest ever reported for carbon materials (0.6-1.1 mmol g -1 at 15 kPa and 25-50 ˚C), and the average isosteric heat of adsorption is typical of a physisorption process: 27 kJ mol -1 . Dynamic experiments carried out in a fixed-bed adsorption unit showed fast adsorption and desorption kinetics and a high CO 2 -over-N 2 selectivity. These adsorbents are able to separate a mixture with 14 % CO 2 (balance N 2 ) at 50 ˚C, conditions that can be considered as representative of post-combustion conditions, and they can be easily regenerated.

Properties and Beneficial Uses of (Bio)Chars, with Special Attention to Products from Sewage Sludge Pyrolysis

“…For effective capture and removal of the CO 2 , high selectivity and adsorption capacity of absorbents are required, in addition to their durability in time, low cost, and ease of regeneration. (Bio)char-based activated carbons have shown adsorption capacity similar to the highest reported for other carbon materials [63].…”

Microbial conversion of pyrolytic products to biofuels: a novel and sustainable approach toward second-generation biofuels

“…Biochar can also be applied as soil amendment to increase soil quality, reduce greenhouse gas emission, and as a sorbent to remove organic and inorganic contaminants from soil and water [152]. Biocharbased activated carbon has shown promising results as a gas adsorbent to capture and store carbon dioxide [58] and hydrogen [94]. Biochar also has the potential to replace coal in direct carbon fuel cell systems (DCFC) [49,79].…”

Hydrodynamics and mass transfer performance of a microreactor for enhanced gas separation processes

“…Typical concentration levels range between 12% and 14% for coal-fired boilers and integrated gasification combined cycles (IGCC), 11-13% for oil-fired boilers, 3-4% for gas turbines, and 7-10% for natural gas fired boilers [2]. It has been widely shown that cost-effective mitigation of CO 2 emissions from these electricity-generating sources can be accomplished by carbon capture and storage (CCS) [3][4][5][6][7][8][9][10] The separation of CO 2 from post-combustion flue gas can be conducted by various approaches, including physical/chemical absorption [11][12][13][14][15][16][17][18][19][20][21], adsorption [22][23][24][25][26][27][28][29][30][31], membrane separation [32][33][34][35][36][37][38][39][40][41][42][43][44], and cryogenic distillation [45][46][47]…”