TY - JOUR

T1 - Influence of thermally modified palygorskite on the viability of polycyclic aromatic hydrocarbon-degrading bacteria

AU - Biswas, Bhabananda

AU - Sarkar, Binoy

AU - Naidu, Ravi

PY - 2016/12/1

Y1 - 2016/12/1

N2 - Thermal activation of palygorskite is considered as a simple and cost-effective method for modifying its structural and surface properties, which can be congenial for the adsorptive removal of environmental contaminants. However, for a more efficient removal of organic contaminants like polycyclic aromatic hydrocarbons (PAH), clay-microbial synergy combining both adsorption and biodegradation is an emerging strategy. In this study, we investigated the compatibility of heat treated palygorskite products (100–900 °C) with a PAH-degrading soil bacterium Burkholderia sartisoli. The mineralogical and physico-chemical properties were characterised in detail, and the bacterial adhesion to the substrate and their growth were observed in relation to these properties. The major variation in the cation exchange capacity (CEC), surface area, water content and the elemental dissolution in the aqueous medium occurred in the palygorskite products heated at extreme temperature (700–900 °C). These changes significantly influenced the bacterial growth and attachment. The maximum viability was imparted by the palygorskite product obtained at 400 °C. Dissolution of Al from products heated above 500 °C also posed inhibitory effect on bacterial growth in the aqueous media. This study provided valuable information about the mechanisms of bacterial viability as affected by modified clay minerals, which is important for developing a novel clay-modulated-bioremediation technology.

AB - Thermal activation of palygorskite is considered as a simple and cost-effective method for modifying its structural and surface properties, which can be congenial for the adsorptive removal of environmental contaminants. However, for a more efficient removal of organic contaminants like polycyclic aromatic hydrocarbons (PAH), clay-microbial synergy combining both adsorption and biodegradation is an emerging strategy. In this study, we investigated the compatibility of heat treated palygorskite products (100–900 °C) with a PAH-degrading soil bacterium Burkholderia sartisoli. The mineralogical and physico-chemical properties were characterised in detail, and the bacterial adhesion to the substrate and their growth were observed in relation to these properties. The major variation in the cation exchange capacity (CEC), surface area, water content and the elemental dissolution in the aqueous medium occurred in the palygorskite products heated at extreme temperature (700–900 °C). These changes significantly influenced the bacterial growth and attachment. The maximum viability was imparted by the palygorskite product obtained at 400 °C. Dissolution of Al from products heated above 500 °C also posed inhibitory effect on bacterial growth in the aqueous media. This study provided valuable information about the mechanisms of bacterial viability as affected by modified clay minerals, which is important for developing a novel clay-modulated-bioremediation technology.

KW - Bacterial viability

KW - Clay-microbial interaction

KW - Heat-treated palygorskite

KW - PAH remediation

U2 - 10.1016/j.clay.2016.07.003

DO - 10.1016/j.clay.2016.07.003

M3 - Journal article

AN - SCOPUS:84995802005

VL - 134

SP - 153

EP - 160

JO - Applied Clay Science

JF - Applied Clay Science

SN - 0169-1317

ER -