Among many biosorbents tested fungal biomasses have proved t

Among many biosorbents tested, fungal biomasses have proved to possess excellent metal uptake potential (Kapoor and Viraraghavan, 1995; Arvind et al., 2014). Other microbial biosorbents such as algae have also been extensively studied and others such as spiriruna have been commercialized for heavy metal removal (Onyancha et al., 2008; Wang and Chen, 2009). Other biosorbents such as agricultural wastes have also been employed. A number of research work have been conducted and documented based on the cyp450 inhibitors of heavy metals by both edible and non-edible varieties of mushrooms and the results show that heavy metals concentration is considerably higher in mushroom than in other agricultural crops. This is an indication that there is an effective mechanism in mushrooms that enables them readily accumulate heavy metal from the environment (Kalac et al., 1996; Fangkun et al., 2010). The aim of this work was to evaluate the potential of roger mushroom as an alternative biosorbent for removal of heavy metal ions from water.
Materials and methods
Results and discussion
Conclusions This study provides significant information regarding the suitability of L. hystrix biomass as biosorbent of selected heavy metals. FTIR analysis reveals the presence of hydroxyl, carbonyl and carboxyl functional groups which are responsible for binding the metal ions. The batch biosorption study shows that the biosorption is pH dependent and the optimum pH for Pb and Cu removal using roger mushroom is 6.0 and 4.5 respectively. The optimum time for adsorption was found to be 30 min for both Pb and Cu. The kinetics of adsorption obeyed the pseudo-second order, while the adsorption isotherm obeyed was Langmuir. The adsorption capacity (qmax) was found to be 3.89 and 8.50 mg/g for Pb and Cu respectively. The recycling of the biomass demonstrates that it can be used in up to three times without losing efficiency. From this study, L. hystrix biomass was found to be suitable biosorbent for heavy metal removal from wastewater pollution.
Acknowledgement The authors are grateful to the National Commission for Science, Technology and Innovation for financial support (Grant No. NACOSTI/ACC/003/005/152).
Introduction The mass of organic wastes produced in our society and the disposal cost has persistently increased over the years and this creates a challenge to process, civil and environmental engineers to develop better cost effective and environmentally secured treatment and discarding methods. The dangers of these organic compounds make their reduction and elimination necessary. Organic elements are commodities and raw materials of industries like petrochemical, oil refinery, explosives, dye, pigment and pesticides industries (Edgehill and Lu Max, 1998). The unacceptable discharge of organic compounds in water banks for a long period of time can cause worsening of water environments, while its consumption by human beings and animals causes liver function failure, kidney damage, central nervous coordination injury, diarrhea and secretion of murky urine (Sarkar and Acharya, 2006). Currently, an approval of trade effluent for release into South African local municipality sewage clearance system does not specify the limits for the BTEX compounds. It is anticipated that, in the upcoming times, stringent regulations in South Africa will be compulsory on the concentrations of these compounds in wastewater before discharge. BTEX compounds have already been selected by the US Environmental Protection Agency as main concern chemicals that need to be condensed to low levels of concentration before discharge (Lin and Huang, 1999). Treatment of BTEX in wastewater becomes a fundamental part of wastewater treatment for oil and chemical industries. An alternative for the removal of BTEX from a solution is by adsorption, of which the recovery of such compounds for likely recycling to the manufacturing process is permitted. The adsorption process is one of the prominent treatment options for the reduction of BTEX pollutants from aqueous media since it is possible to recover the adsorbent and adsorbate (Aivalioti et al., 2012). The adsorption of BTEX compounds can be achieved by macro reticular resin (Cornel and Sontheimer, 1986; Crook et al., 1978) and activated carbon (Furuya et al., 1997; Noll et al., 1994). Other adsorbents may include carbon nano tube, diatomite (Aivalioti et al., 2010, 2012) and organo-clay. All of the studies mentioned above investigate removal at higher concentration. None have been recorded on the low range concentration (less than 1 ppm) adsorption of BTEX using a polystyrenic resin. Hence, it was decided to embark on this investigation.