Effect of temperature on sorption of metals by silica-supported 2-(aminomethyl)pyridine. Part I: Binding equilibria

According to the results, the binding enthalpy is negative for both sulfuric acid and metal sulfates. Basicity and metals binding strength of the adsorbent thus decrease with temperature. The affinity for copper remains sufficiently high even at 90 °C to ensure high uptake selectivity from a concentrated ZnSO4 solution. At the same time the amount of metal adsorbed remains constant or even increases with increasing temperature.