Experimental investigation of adsorption of copper from aqueous solution using vermiculite and clinoptilolite

Considering the point that the existence of heavy metals in the wastewater are so dangerous for the environment and it would have many bad consequences for all the creatures including human beings, we must try out the ways that make us capable of adsorbing these heavy metals. In order to accomplish this goal we should use a method called adsorbing. In this study the adsorption of copper ions in hydrated copper nitrate [Cu [NO[3]][2], 3H[2]O] aqueous solution on natural zeolite [Clinoptilolite] and vermiculite was studied in batch reactors. The effect of temperature [25, 50, 75 °C], solution pH [1.00-5.5] and concentration effect on the traditionally defined adsorption isotherm in the adsorbate range 100-325 mg/L for clinoptilolite and 100- 650 mg/L for vermiculite on the removal of copper was studied. The results showed that an increase in pH increases the adsorptivity of vermiculite. Pseudo second order model best described the reaction rate. Batch adsorption experiments conducted at room temperature [25 +/- 1 °C] showed that the adsorption pattern followed the Langmuir and Freundlich isotherm models. Optimum conditions for adsorption were determined at pH 5.5, and vermiculite and clinoptilolite at a dose of 3g. The concentration of metal ions was measured by Atomic Absorption Spectrometer [AAS]. The results indicated that vermiculite and clinoptilolite are appropriate for adsorbing copper ions

Adsorption of chromium and copper in aqueous solutions using tea residue

In this study, adsorption of copper and chromium was investigated by residue of brewed tea [Tea Waste] from aqueous solutions at various values of pH. It was shown that adsorbent dose, copper and chromium ion concentrations in such solutions influence the degree of these heavy metal ions' obviation. The adsorption level of the prepared solutions was measured by visible spectrophotometer. The tea residue adsorbed copper [II] and chromium [VI] ions at initial solution pH by 25% and 3%, respectively. During the experiments the peak adsorption occured in hydrated copper nitrate aqueous solution at pH range of 5-6. Likewise the maximum adsorption appeared in potassium chromate aqueous solution at pH range of 2-3. In addition, tea residue adsorbed about 60 mg/g of copper [II] ion at pH=5, while chromium adsorption was registered at about 19 mg/g at pH=2. The data obtained at the equilibrium state, was compared with Langmuir and Freundlich models. Results showed that regarding the kinetics of adsorption, the uptake of copper [II] and chromium [VI] ions by tea residue was comparatively faster, with the adsorption process exhaustion completed within the first 20 min of the experiments. Furthermore, results revealed that adsorption data concerning the kinetic phase is closely correlated with a pseudo-second order model with R[2] > 0.99 for copper [II] and chromium [VI] ions