Effect of Rank and Petrographic Composition on the Swelling Behavior of Coals

Understanding reactions and pore-forming mechanisms between waste cotton woven and FeCl3 during the synthesis of magnetic activated carbon

“…El alto contenido de oxígeno de la muestra es característico de un material con alto contenido de polisacáridos como la celulosa o hemicelulosa, propia del tejido de algodón. Este elevado nivel de oxígeno resulta beneficioso para el desarrollo de matrices de macroporos y mesoporos, debido a que los compuestos superficiales que tienen oxigeno resultan reactivos y se consumen a altas temperaturas, por lo cual producen espacios que permiten entrar al agente activante y ensanchar los poros al consumir el carbono de las paredes internas del material (Gentzis et al, 1996). En el caso específico del proyecto, resulta útil debido a la magnitud de las moléculas de colorantes, que son absorbidos principalmente por carbones mesoporosos.…”

Production and Characterization of Activated Carbon from Coal for Gold Adsorption in Cyanide Solutions

“…This could be related to the barrier effect of ash, which inhibits fixed carbon-steam contact. The negative behavior corresponds to activated carbons when the fixed carbon content is approximately 66%, and according to Gentzis et al (1996), higher rank coal corresponds to lower reactivity and elasticity.…”

“…Carbon content influences gold adsorption due to its relationship with C-C bonds, which corresponds to graphite layers, where the aurocyanide ionic pair is preferentially adsorbed. Oxygen content is related to a higher reactivity: surface compounds containing oxygen are consumed more easily at high temperatures, generating spaces into the structure that allow the entrance of activating agents to consume fixed carbon, thus widening the pores (Gentzis, Hirosue, and Sakaki, 1996). According to the above, activated carbons produced from A and G coal, theoretically, may produce a higher content of macropores.…”

“…According to the above, activated carbons produced from A and G coal, theoretically, may produce a higher content of macropores. In addition, H content is associated with volatile matter release (Gentzis et al, 1996;Niksa, 1995). Therefore, devolatilization capacity should be similar in all the original coals used.…”

“…However, differences in O content (20,88%) for A coal could explain the differences observed in IN values. According to Gentzis et al (1996), oxygen content is related to the presence of vitrinite maceral. Vitrinite is more easily broken at high temperatures, generating a porous matrix.…”