Removal of Cu2+ and Ni2+ from aqueous solution using SnO2 nanomaterial effect of: pH, time, temperature, interfering cations

Abstract

Tin oxide, SnO2, nanomaterial was synthesized and tested for the removal of Cu2+ and Ni2+ ions from aqueous solutions. Various parameters for the binding were investigated in batch studied, which included pH, time, temperature, and interferences. In addition, isotherm studied were performed to determine the maximum binding capacity for both Cu2+ and Ni2+ ions. The optimal binding pH determined from the effects of pH were to be at pH 5 for both the Cu2+ and Ni2+ ions. The isotherm studies were performed at temperatures of 4°C, 25 °C, and 45 °C for both the Cu2+ and Ni2+ ions and were found to follow the Langmuir isotherm model. The binding capacities for the Cu2+ ions were 2.63 mg/g, 2.95 mg/g and 3.27 mg/g at the aforementioned temperatures, respectively. Whereas the binding capacities for Ni2+ were 0.79 mg/g, 1.07 mg/g, and 1.46 mg/g at the respective temperatures. The determined thermodynamic parameters for the binding showed that the binding processes for the reactions were endothermic, as the ΔG was observed to decrease with decreasing temperatures. As well the ΔH was 28.73 kJ/mol for Cu2+ (III) and 13.37 kJ/mol for Ni2+. The ΔS was observed to be 92.65 J/mol for Cu2+ and 54.53 J/mol for Ni2+. The free energy of adsorption for the Cu2+ was determined to be 13.99 kJ/mol and the activation energy for the binding of Ni2+ was determined to be 8.09 KJ/mol. The activation energy data indicate that the reaction was occurring through chemisorption

Carbon Nanofibers: A New Adsorbent for Copper Removal from Wastewater

“…For the entire temperature range studied, the ∆G • values were negative, this indicating that the adsorption process is spontaneous. These values are lower than 18 KJ·mol −1 , characteristic of a physisorption [18], and this agrees with the result obtained from R L Langmuir parameter (see Table 6).…”

“…When the pH increases to between 4 and 10, the cooper adsorption increased to its maximum at pH 10 (q e = 8.88 mg·g −1 ). Above the isoelectronic pH, the nanomaterial surfaces have a negative charge and attract the metal ions facilitating the adsorption [18,37].…”

“…The increase of adsorption with temperature can be due to different factors, such as a change in the pore size of the nanofibers and/or an increase of the active sites. In addition, the collisions between the metal and the surface of the nanofibers are greater, thereby contributing to a rise in the adsorption capacity [18].…”

Investigation into the thermodynamics and kinetics of the binding of Cu2+ and Pb2+ to TiS2 nanoparticles synthesized using a solvothermal process

“…Whereas ∆G for the sorption of Pb 2+ onto the TiS2 was observed to range from -2.55 kJ/mol to -16.33 kJ/mol from 4˚C to 45˚C, which indicates that the sorption process becomes more spontaneous as the temperature increases. In a previous study conducted by Rafiq [42]. The data presented in the current study are within range and are comparable to the data presented in similar studies [37][38][39][40][41][42].…”

“…Where C is the concentration of the ions at any given time, t, is the adsorption time in minutes, and k is the rate constant for the metal-ion adsorption onto the nano-sorbent at equilibrium. The zeroth order kinetic model has been found to fit with many adsorption studies [31,42,45,46].…”