Biosorption of cobalt (ii) ions using palm kernel mesocarp fibre

• Main Author: Yu, Hui Fang
• Format: Final Year Project / Dissertation / Thesis
• Published: 2019
• Subjects: TD Environmental technology. Sanitary engineering
• Online Access: http://eprints.utar.edu.my/3913/1/fyp_EV_2019_YHF.pdf; http://eprints.utar.edu.my/3913/
• Institution: Universiti Tunku Abdul Rahman

Heavy metal pollution in water bodies such as cobalt can originate from chemical and oil industry, nuclear industry, as well as industries that produce paints and fertilisers. Excessive cobalt exposure can lead to toxic and carcinogenic effects and thus its release to the environment should be regulated. Meanwhile, palm kernel mesocarp fibre (PKMF) is a biomass by-product resulting from the extraction of palm oil from palm fruit bunch. The large amount of PKMF produced from this process can be utilised as biosorbent to adsorb cobalt (II) ions from wastewater. This research proved that PKMF has the potential to adsorb cobalt (II) ions from simulated wastewater. Modification using 1M sodium hydroxide (NaOH) was done to the PKMF as its unmodified form did not yield high removal efficiency and adsorption capacity. Through this research, it was found that modified PKMF could achieve removal efficiency of almost 2 times that of unmodified PKMF. The effects of parameters such as pH, particle size, time, dosage and initial concentration on the biosorption of cobalt (II) ions using PKMF were investigated in this research. The optimum pH was found to be 4.5 and the optimum particle size used was 63 µm. The cobalt uptake was found to be rapid and approximately 75 % of total cobalt uptake was achieved within 10 minutes of contact. Sorption kinetic models and adsorption isotherm studies were also carried out where the adsorption fit well with pseudosecond-order kinetic model and Freundlich isotherm respectively. Through the Langmuir isotherm study, the maximum sorption capacity was determined to be10.88 mg/g. Characterization using Scanning Electron Microscopy (SEM) was conducted on the PKMF and the changes on the surface morphology were examined. The adsorption capacity and removal efficiency of the PKMF can be further improved by heating or boiling the PKMF in NaOH. Further studies such as dispersive X-ray (EDX) analysis, Fourier-Transform Infrared Spectroscopy (FTIR) and thermogravimetry analysis (TGA) can be carried out to enable chemical characterisation of PKMF as a result of the agreement with pseudo-second-order kinetic model.