P. putida as biosorbent for the remediation of cobalt and phenol from industrial waste wastewaters

Abstract

The current work focused on the feasibility of treating industrial wastewater containing phenol and cobalt (Co) by adsorption, biosorption, and bioadsorption to determine the effectiveness of each technology. To study the effect of bioadsorption on the removal of phenol and Co, initial studies on biological degradation and adsorption of bacteria and activatedcarbon (AC) had been conducted separately. Results showed that the Langmuir model was the best fitted model for the experimental data over the whole range tested for both the phenol and Co adsorption indicating a monolayer behavior of the consumption process. Moreover, biodegradation results of phenol and Co by P. putida showed a noticeable uptake of phenol to certain concentrations up to 1100 ppm as maximum phenol concentration that P. putida could degrade in which increasing the concentration showed no degradation. Additionally, the optimum phenol concentration by which the degradation was higher and faster was found to be at 700 ppm. In the case of Co, the conducted experiment showed an increase in the uptake of Co with an increase in the initial concentrations up to 10 ppm of Co, and then there was no Co uptake. The bioadsorption experiment which aimed to test the biodegradability of phenol by AC with P. putida and compare it with the degradation of phenol by each factor alone indicated that the uptake of phenol was higher in P. putida and AC + P. putida than using AC alone. Thus, the obtained results clearly showed the effectiveness of using P. putida for the removal of phenol and cobalt from the contaminated effluents.