Evaluation of sewage sludge and slow pyrolyzed sewage sludge-derived biochar for adsorption of phenanthrene and pyrene

• Published in: Bioresource technology 2015-09, Vol.192, p.618-626
• Main Authors: Zielińska, Anna, Oleszczuk, Patryk
• Format: Article
• Language: English
• Subjects: Adsorption; Biochar; Charcoal - chemistry; Heating - methods; Materials Testing; Phenanthrene; Phenanthrenes - chemistry; Phenanthrenes - isolation & purification; Polycyclic Aromatic Hydrocarbons - chemistry; Polycyclic Aromatic Hydrocarbons - isolation & purification; Pyrene; Pyrenes - chemistry; Pyrenes - isolation & purification; Sewage - chemistry; Sewage sludge; Water Pollutants, Chemical - chemistry; Water Pollutants, Chemical - isolation & purification; Water Purification - methods
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2015.06.032

•The conversion of sewage sludges into biochar increased their sorption capacity.•Pyrene was adsorbed better on the tested materials than phenanthrene.•Sewage sludge-derived biochars can be a good adsorbent for PAHs removal from water. The present study investigated the sorption of phenanthrene (PHE) and pyrene (PYR) by sewage sludges and sewage sludge-derived biochars. The organic carbon normalized distribution coefficient (logKOC for Cw=0.01 Sw) for the sewage sludges ranged from 5.62Lkg−1 to 5.64Lkg−1 for PHE and from 5.72Lkg−1 to 5.75Lkg−1 for PYR. The conversion of sewage sludges into biochar significantly increased their sorption capacity. The value of logKOC for the biochars ranged from 5.54Lkg−1 to 6.23Lkg−1 for PHE and from 5.95Lkg−1 to 6.52Lkg−1 for PYR depending on temperature of pyrolysis. The dominant process was monolayer adsorption in the micropores and/or multilayer surface adsorption (in the mesopores), which was indicated by the significant correlations between logKOC and surface properties of biochars. PYR was sorbed better on the tested materials than PHE.