Simultaneous phenol removal and biological reduction of hexavalent chromium in a packed‐bed reactor

Abstract

BACKGROUND: Phenol and hexavalent chromium are considered industrial pollutants that pose severe threats to human health and the environment. The two pollutants can be found together in aquatic environments originating from mixed discharges of many industrial processes, or from a single industry discharge. The main objective of this work was to study the feasibility of using phenol as an electron donor for Cr(VI) reduction, thus achieving the simultaneous biological removal/reduction of the two pollutants in a packed-bed reactor.

Evaluation of the bioremoval of Cr(VI) and TOC in biofilters under continuous operation using response surface methodology

“…The removal rates obtained by the works of Alam (2004), Middleton et al (2003), Dermou and Vayenas (2008), Philip (2009), Brunet et al (2006); Ekenberg et al (2005); Tziotzios et al (2008), and Ahmad et al (2010) were close to 100%. The removals obtained by this work were slightly lower except for experiment 13 (Table 2) in which the removal result was the same.…”

“…These authors demonstrated that a number of viable process arrangements and microbial technologies can reduce Cr(VI) to Cr(III), including aerobic suspended growth systems, aerobic attached growth systems, and anoxic attached growth systems. Hence, most studies are directed towards the evaluation of the feasibility of the process at the pilot-scale level (Brunet et al 2006;Ekenberg et al 2005;Tziotzios et al 2008;Ahmad et al 2010). Reductions of *100% have been obtained from initial Cr(VI) concentrations ranging from 5.5 to 81 mg l -1 in anaerobic and aerobic bioreactors.…”

Isolation and Growth Characteristics of Chromium(VI) and Pentachlorophenol Tolerant Bacterial Isolate from Treated Tannery Effluent for its Possible Use in Simultaneous Bioremediation

“…The literature available on simultaneous bioremediation of Cr(VI) and PCP by a single indigenous isolate is very scanty. Other researchers have employed either a coculture or a consortium of pure cultures [19,21] or natural isolates from other than tannery effluents [20]. However, it would be always better to use single strain, if available, as it is convenient to handle and maintain under standard cultural and nutritional conditions.…”

“…However, only a limited work has been done toward simultaneous bioremediation of Cr(VI) and phenolics in the tannery effluents [19][20][21], particularly by native microbes. Most of the researchers have employed either coculture or microbial consortium for simultaneous bioremediation of PCP and Cr(VI).…”

Response Surface Modeling for Co-Remediation of Cr6+and Pentachlorophenol byBacillus cereusRMLAU1: Bioreactor Trial and Structural and Functional Characterization by SEM-EDS and FT-IR Analyses

“…Therefore, wastewater contaminated with Cr 6C and phenolics should be treated carefully before being discharged into receiving water bodies. Limited research has been performed on native microbes for simultaneous bioremediation of Cr 6C and phenolics in industrial effluent (Srivastava et al 2007;Tziotzios et al 2008;Tripathi and Garg 2013). Therefore, the simultaneous PCP and Cr 6C removal by a native bacterial isolate represents an attractive alternative treatment strategy.…”