An ability of fresh banana peel without surface modification was evaluated for the removal of lead ions from aqueous solution. Batch adsorption was performed at room temperature. The experimental conditions including dosage contact time initial concentration of lead( II) ion were studied. The characterization of fresh banana peel was carried out by Fourier-transform infrared spectroscopy (FTIR) and energy dispersive X-ray fluorescence ( ED-XRF) . The isotherm models of Langmuir and Freundlich were used to describe the adsorption mechanism involving the relationship between adsorbent surface capacity and adsorbed degree of lead(II)ion in the equilibrium conditions. The experimental data fitted well to the Langmuir isotherm with a correlation coefficient of r2 greater than 0.86. The Maximum adsorption capacity (qm) was found to be 0.9151 mg/g. The results of ED-XRF of fresh banana peels before and after treatment with lead( II) ion confirmed that lead( II) ion was occupied onto the surface of fresh banana peel. Moreover the inside of fresh banana peels was found the lead(II)ion larger than the outside peels. It was concluded that waste of banana could be used as a low-cost adsorbent for removal of lead(II)ion from aqueous solution based on a simple adsorption method.

The biosorption of phosphate using modified cassava waste were studied. Cassava pulp was modified in methylamine for the adsorption of phosphate ion in aqueous solution. XRD SEM and FTIR result confirmed the surface modification of modified cassava waste. The adsorption experiments were conducted in a batch reactor. The studied parameters included pH contact time and initial concentrations. The amount of phosphate in the solution was measured by Vanadomolybdophosphoric acid method. Optimum conditions of adsorption were 0.10 g of modified cassava waste pH 4 and 5 hour of contact time at 25 mg/L of initial phosphate concentration. Kinetic of adsorption were studied by using the pseudo-first and pseudo-secondorder models at room temperature. The results indicated that the pseudo-second-order model best described adsorption kinetic data. The Langmuir and Freundlich adsorption models were applied to describe the isotherms and isotherm constants. The adsorption of modified cassava fitted well with the Langmuir model and the maximum adsorption capacity of 5.128 mg/g; and the active site of adsorption was amine functional group. Phosphate released in water reach equilibrium within 4 days.

Silica is an amorphous and nanometer scale voids and porous form of silicon dioxide. As long known for its high specific surface area synthetic silica has been used to adsorb water readily and applied for keeping many biological products dry protecting equipment from moisture damage. In the study the researchers have interested in making the tentative eco-friendly dehumidifying products based on the silica extract from bamboo leaves. The extraction procedures were performed by boiling dry bamboo leaves with various concentrated hydrochloric acid (HCl) at 1 2 3 and 4 M then burning them at 650oC for 4 hr before analyzing the purity of the biosilica with the X-ray Fluorescence Method. The results showed that the highest purity of the biosilica sample at 96% could be obtained after treated with 4 M HCl comparing with the control commercial silica. By hygroscopic test the extracted biosilica with 2 M HCl showed the highest moisture absorption properties close to the commercial silica. While the highest adsorption capacity was found in the biosilica sample treated with 3 M HCl. The dehumidifying efficiencies of all HCl treated biosilica power were not much different comparing to the commercial silica gel. Instead of using synthetic silica therefore this high environmentally friendly and cheaper biosilica from bamboo leaves can preferably be decent and further applied in green industry.

The biosorption of Rhodamine B using modified water hyacinth roots was studied. The adsorption experiments were conducted in a batch setup. Parameters affecting the adsorption of Rhodamine B including pH of a solution adsorption time adsorbent dose and dyes concentration were investigated. With the 80 mg/L Rhodamine B solution of pH 6.0 adsorption time of 60 min and 0.10 g of modified water hyacinth roots the kinetic models pseudo-first order and pseudo-second order kinetic model were applied to examine the kinetic adsorption. The adsorption kinetic data correlates with pseudo-second order kinetic model. The Langmuir and Freundlich adsorption models were applied to describe the isotherms and isotherm constants. Adsorption isotherm data correlates with Langmuir adsorption model. The maximum adsorption capacity of modified water hyacinth roots for Rhodamine B was found to be 63 mg/g

In this study autoclaved aerated concrete (ACC) were investigated as low-cost andsimple adsorbents for removal of Pb(II) from aqueous solution. The adsorption of Pb(II) wascarried out by batch experiments as a function of solution pH adsorbent dosage contacttime initial Pb(II) concentration and temperature. The experimental data were analyzed bythe Langmuir Freundlich Temkin and D-R isotherm models. The Langmuir isotherm modelis more suitable. The monolayer adsorption capacity of ACC was found to be 3.99 mg g−1.The adsorption of Pb(II) onto ACC was physical in nature. The kinetic studies of Pb(II)demonstrated that the adsorption of Pb(II) onto ACC adsorbents followed a pseudosecond-order model with a good correlation.