Treatment of electronics industry effluent using low-cost and commercial adsorbents: A comparative study

Abstract

In the present study, the potential of two low-cost adsorbents namely kenaf (Hibiscus cannabinus L.) bast fiber and golden apple snail (Pomacea canaliculata) shell to treat heavy metals concentration in electronics industry effluent has been investigated. The physicochemical properties and adsorption mechanisms were determined using several analytical instruments such as Fourier Transform Infrared (FTIR) Spectrometer, Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) Spectrometer. With an initial metal ion concentration of 50 mg/L, the adsorption of Cd(II), Cr(VI), Cu(II), Ni(II), Pb(II) and Zn(II) was optimized at acidic media (solution pH of 4.0-6.0), 60 minutes of contact time and 0.5 g of adsorbent dosage. The equilibrium data of metal ions adsorption onto kenaf bast fiber and golden apple snail shell followed the Langmuir isotherm model. Based on Langmuir isotherm model, the adsorption capacity of adsorbents for metal ions was in the order of Pb(II) > Cu(II) > Zn(II) > Ni(II) > Cd(II) > Cr(VI). Golden apple snail shell was able to remove Cr(VI), Ni(II) and Zn(II) ions from the electronics industry effluent at a higher capacity as compared to kenaf bast fiber and commercial mangrove stem derived activated carbon. The presence of carbonate functional group in green apple snail shell favored the adsorption of metal ions. Overall, results from this study suggest that kenaf bast fiber and golden apple snail shell have great potential to be used as alternative adsorbents to treat industrial effluents.