SORPTION AND MICROBIAL DEGRADATION OF TOLUENE ON A SURF ACTANT-MODIFIED-ZEOLITE SUPPORT

摘要

We conducted laboratory studies to test the feasibility of using a reactive nutrient-amended microbial support system comprised of surfactant-modified zeolite (SMZ) to stimulate biodegradation of petroleum hydrocarbons. Toluene was used as a model hydrocarbon contaminant. Batch isotherm experiments showed that toluene sorption on SMZ and nutrient-amended SMZ (N-SMZ) was similar, resulting in a K_d of 13.0 L kg~(-1) , and toluene desorption reached equilibrium within 2 h. The first-order toluene biodegradation rate coefficient in solution-only aerobic microcosms was 0.24 h~(-1), while in SMZ and N-SMZ slurry-phase cultures the rate coefficient was 0.13 h" . Transport simulations suggest that a 1 -m wide N-SMZ permeable barrier could microbially degrade toluene to below the drinking water standard.