Effects of bamboo-charcoal modified by bimetallic Fe/Pd nanoparticles on n-hexane biodegradation by bacteria Pseudomonas mendocina NX-1

The high hydrophobicity of n -hexane is the main reason why it is difficult to be removed biologically. In this study, the effects of bamboo-charcoal modified by bimetallic Fe/Pd (BBC) on n -hexane biodegradation by Pseudomonas mendocina NX-1 (PM) was investigated. The n- hexane removal efficiency was increased in the presence of BC. The highest n- hexane removal efficiency at 90.0% was achieved at 0.05 g L −1 BCE and 3 g L −1 NH 4 + under pH 7.7 and 35 °C. Additionally, protein content (45.9 μg mL −1 ) and negative cell surface zeta potential (−26.4 mV) were increased during biodegradation process, with PM-BBC being 43.1 μg mL −1 and 19.1 mV. Bacterial growth was improved and maximum cell surface hydrophobicity was obtained after 20 h, which was 59.4% higher than the control with PM-BBC (37.7%) or PM (16.1%), showing biodegradation products of 1-butanol and acetic acid. The results indicate that BBC improved n- hexane biodegradation efficiency by promoting bacterial growth, reducing cell zeta potential, exposing hydrophobic proteins, and increasing cell surface hydrophobicity of bacterial strain NX-1. This investigation suggests that BBC-enhanced biodegradation can be promising to treat n- hexane-containing gas.