Treatment of naphthalene-2-sulfonic acid from tannery wastewater by a granular activated carbon fixed bed inoculated with bacterial isolates Arthrobacter globiformis and Comamonas testosteroni.
The kinetics of naphthalene-2-sulfonic acid (2-NSA) adsorption by granular activated carbon (GAC) were measured and the relationships between adsorption, desorption, bioavailability and biodegradation assessed. The conventional Langmuir model fitted the experimental sorption isotherm data and introduced 2-NSA degrading bacteria, established on the surface of the GAC, did not interfere with adsorption. The potential value of GAC as a microbial support in the aerobic degradation of 2-NSA by Arthrobacter globiformis and Comamonas testosteroni was investigated. Using both virgin and microbially colonised GAC, adsorption removed 2-NSA from the liquid phase up to its saturation capacity of 140 mg/g GAC within 48 h. However, between 83.2% and 93.3% of the adsorbed 2-NSA was bioavailable to both bacterial species as a source of carbon for growth. In comparison to the non-inoculated GAC, the combination of rapid adsorption and biodegradation increased the amount (by 70-93%) of 2-NSA removal from the influent phase as well as the bed-life of the GAC (from 40 to >120 d). A microbially conditioned GAC fixed-bed reactor containing 15 g GAC removed 100% 2-NSA (100 mg/l) from tannery wastewater at an empty bed contact time of 22 min for a minimum of 120 d without the need for GAC reconditioning or replacement. This suggests that small volume GAC bioreactors could be used for tannery wastewater recycling.
Song
Zhi
Z
Research School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK.
Edwards
Suzanne R
SR
Burns
Richard G
RG
D000327:Adsorption; D001173:Arthrobacter / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001682:Biological Availability; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry; D020585:Comamonas / Q000378:metabolism*; D007700:Kinetics; D009282:Naphthalenesulfonates / Q000378:metabolism*; D013633:Tanning; D014865:Waste Disposal, Fluid / Q000379:methods*
D009282:Naphthalenesulfonates; C511690:naphthalene-2-sulfonic acid; D002244:Carbon