Chars as carbonaceous adsorbents/catalysts for tar elimination during biomass pyrolysis or gasification

A critical review on sustainable biochar system through gasification: Energy and environmental applications

“…The generation of tars during the biomass gasification is harmful to the system, which could 274 cause mechanical breakdown and deactivate the catalysts in the refining process (Shen, 2015). 275…”

“…The relatively high 278 surface area and porous structure of biochar could improve the dispersion of metal ions and 279 facilitate the transport of reactant molecules into the internal surfaces of catalysts, which make 280 them good catalyst supports (Shen & Yoshikawa, 2013). The major mechanisms of tar removal 281 by biochar-based catalysts are physical adsorption, thermochemical reforming, and a 282 combination of adsorption and catalytic conversion (Shen, 2015). 283…”

Catalytic reforming of pyrolysis tar over metallic nickel nanoparticles embedded in pyrochar

“…However, the catalytic activities of dolomite and olivine for tar conversion leave room for improvement, so the motivation is the search for catalytic additives [15]. Recently, chars derived from coal or biomass have been used as low-cost carbonaceous catalysts [16][17][18][19][20] and adsorbents [21][22][23] in tar elimination. Char itself exhibits a fair catalytic activity for tar reforming, which is often influenced by pore size, surface area and mineral contents.…”

Biochar Modification, Thermal Stability and Toxicity of Products Modification

“…Note to the content of the publication LO Before After CH 3 OH + Improvement of adsorption capacity to tetracycline (Jing et al, 2014) H 2 O 2 + Utilization of the role of -OH radicals (G. FeCl 2 , FeSO 4 , Ni(NO 3 ) 2 + Preparation of magnetic biochar (Safarik et al, 2012) GRAPHITE+ Py-SO 3 + Sorption material for PAU sorption KMnO 4 , HNO 3 + Testing of changes of adsorption capacity Nanoparticles of metals, Fe(NO 3 ) 3 , Ni(NO 3 ) 2 + Introduction of metal nanoparticles into the structure Monomers, oligomers, polymers + Preparation of polymer composite materials (Das et al, 2015) KOH, NaOH + Preparation of a catalyst of alkaline character (Abdul Hamid et al, 2014) HNO 3 , H 2 SO 4 + Improvement of adsorption capacity to Cd and Al ions (Qian et al, 2015) Metal salts (Fe, Pd, Pt, Ni) + Preparation of a catalyst biochar -metal (Shen, 2015) KOH, NaOH + Increase of biochar surface (Gu and Wang, 2013) (Tan et al, 2016) Clays, kaolin, montmorillonite + New material -testing of adsorption kinetics (methylene blue) (Yao et al, 2014) H 2 SO 4 , solution KOH + Improvement of adsorption capacity to tetracycline (P. HNO 3 50 % + Formation of carbonaceous nanoparticles (Manav et al, 2016) CNT (0.01-1%) + Improvement of sorption capacity (Inyang et al, 2014) Lignite + Joint processing -hydrothermal (Z. MnCl 2 . 4H 2 O + Modifi cation of biochar with MnO x Improvement of sorption capacity to As and Pb KMnO 4 + HCl + Preparation of composite Birnessite -Biochar HNO 3 + H 2 SO 4 (1:1) + Na 2 S 2 O 4 + Amidation of biochar (reduction of NO 2 groups to -NH 2 ), increase of sorption capacity to Cu 2+ (Yang and Jiang, 2014) Chitosan + Sorption of heavy metals and biological activity Fe 3 O 4 + Preparation of sorbents in a ball mill -sorption capacity to antibiotics (Shan et al, 2016) Legend: LO -Reference worldwide-used pharmaceutical products, such as isobrufen (Essandoh et al, 2015), tetracycline (Liao et al, 2013), acetaminophenon (Im et al, 2014), aspirin (Essandoh et al, 2015) toxic industrial substances (Chen and Chen, 2009;Wang et al, 2013), explosives (Oh and Seo, 2014;Oh and Seo, 2015) etc.…”