Peanut Shell Case Study

Witek-Krowiak et al., (2010) researched on the use of peanut shell to remove heavy metals from water solution. Cu (II) and Cr (III) ions were the heavy metals in this research, using Langmuir, Freundlich, Redlich–Peterson and Sips models to examine data gotten from the tests. The preparation of the bio sorbent material (peanut shell) was prepared by washing with pipe and refined water for about 1-2hrs to remove dirt and colour, the washed peanut shells were dried in an oven for a day then mashed to particles size less than 30μm. The sampling for the tests was done in batch mode, taking into forethought the issue of initial pH, initial biomass concentration and temperature. Various concentrations of the metals in water solution ranging from 10mg/L to 1000mg/L at modified pHs were measured to 100ml and poured into a 250ml Erlenmeyer flasks. The prepared peanut shells were put in the solutions and left for a day and particles were removed from the mixture by filtration. The fluid given off from the filtration process was tested atomic absorption spectroscopy (AAS) for the metal concentration. The analysis showed that for 1g of peanut shell 25.39mg of Cu (II) and 27.86mg of Cr (III) were removed (at given optimum conditions), therefore peanuts shells proved to be an efficient bio sorbent. Studies were also carried out on the use of cashew nut shell to remove Cu (II) ions present in water solutions (SenthilKumar et al., 2010). The cashew nut shells were washed to remove dirt and dried to remove moisture at room temperature, the dried sample were mashed using a still mill so that particle sizes between 200-30 mesh were collected for use. The implications of pH of the solution, the bio sorbent concentration, contact time, initial Cu (II) ion concentration and temperature were considered for efficiency observation. The sampling for the test was performed in batch mode, using a rotatory shaker to mix the absorbent and the water solution. The concentration of Cu (II) in the water solution after addition of the absorbent was checked using AA6300 Atomic absorption spectrometer. The results gotten from the test were analysed using Langmuir and Freundlich isotherm models. The study showed that the absorption capacity for Cu (II) ion is 20.00mg per 1g of bio sorbent at pH 5 in 30mins at 30°C, the results proved cashew nut …show more content…
The investigation took into consideration the implication of contact time, initial concentration, pH and temperature on the adsorption process. The absorbent (TFS-CE) was prepared using graft copolymerization of hydroxyethylmethacrylate on shells of the tamarind fruit with the aid of N-N’-methylenebisacrylamide for crosslinking. Using batch method, concentrated solutions containing 100mg of TFS-CE was added to samples of water solution containing Cu (II) ions (50cm3 volume) with concentration level of 25-300 mg.dm-3, the initial pH value was adjusted using a pH meter. The mixture was agitated at 200rpm using a temperature monitored water bath shaker. The solvent was filtered out after equilibrium and tested for Cu (II) ions concentration using the Atomic absorption spectrometer. Data analysis was carried out using pseudo-second-order model and Arrhenius and Eyring equations. The adsorption process was efficient, endothermic, and followed the Langmuir isotherm model with TFS-CE having maximum adsorption capacity of 64.1mg.g-1 at temperature of 300K and pH of