TY - JOUR
T1 - Biogas upgrading
T2 - Optimal activated carbon properties for siloxane removal
AU - Cabrera-Codony, Alba
AU - Montes-Morán, Miguel A.
AU - Sánchez-Polo, Manuel
AU - Martín, Maria J.
AU - Gonzalez-Olmos, Rafael
PY - 2014/6/17
Y1 - 2014/6/17
N2 - A total of 12 commercial activated carbons (ACs) have been tested for the removal of octamethylcyclotetrasiloxane (D4) in dynamic adsorption experiments using different carrier gases and D4 concentrations. Characterization of the ACs included several physical and chemical techniques. The D4 adsorption capacities were strongly related with the textural development of the ACs. Results showed that the optimum adsorbent for D4 is a wood-based chemically activated carbon, which rendered an adsorption capacity of 1732 ± 93 mg g-1 using 1000 ppm (v/v) of D4 with dry N2 as the carrier gas. When the concentration of D4 was lowered to typical values found in biogas, the adsorption capacity was halved. The presence of major biogas compounds (i.e., CH4 and CO2) and humidity further reduced the D4 adsorption capacity. The polymerization of D4 over the surface of all ACs was found to be relevant after prolonged contact times. The extent of this phenomenon, which may negatively affect the thermal regeneration of the AC, correlated reasonably well with the presence of phenolic and carboxylic groups on the carbon surfaces.
AB - A total of 12 commercial activated carbons (ACs) have been tested for the removal of octamethylcyclotetrasiloxane (D4) in dynamic adsorption experiments using different carrier gases and D4 concentrations. Characterization of the ACs included several physical and chemical techniques. The D4 adsorption capacities were strongly related with the textural development of the ACs. Results showed that the optimum adsorbent for D4 is a wood-based chemically activated carbon, which rendered an adsorption capacity of 1732 ± 93 mg g-1 using 1000 ppm (v/v) of D4 with dry N2 as the carrier gas. When the concentration of D4 was lowered to typical values found in biogas, the adsorption capacity was halved. The presence of major biogas compounds (i.e., CH4 and CO2) and humidity further reduced the D4 adsorption capacity. The polymerization of D4 over the surface of all ACs was found to be relevant after prolonged contact times. The extent of this phenomenon, which may negatively affect the thermal regeneration of the AC, correlated reasonably well with the presence of phenolic and carboxylic groups on the carbon surfaces.
UR - http://www.scopus.com/inward/record.url?scp=84902579128&partnerID=8YFLogxK
U2 - 10.1021/es501274a
DO - 10.1021/es501274a
M3 - Article
C2 - 24837651
AN - SCOPUS:84902579128
SN - 0013-936X
VL - 48
SP - 7187
EP - 7195
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 12
ER -