- Summary
- References
- Related Articles
Lead has caused serious environmental pollution due toits toxicity, accumulation in food chains and persistence innature. In this paper, lead removal from aqueous solutions wasinvestigated using condensed tannin gel adsorbent synthesized froma natural tannin compound. It is found that the adsorption isstrongly affected by pH values of aqueous solutions. Within pHrange of 3.5-6, when initial lead concentration is 100 mg/L,removal efficiency is more than 90%. Adsorption equilibrium isreached within 150 minutes. The adsorption isotherm fits well withthe Langmuir equation, by which the saturated adsorption uptake of190 mg Pb2+/g dry tannin gel adsorbent is obtained. By means of thermodynamics analysis, it is revealed that the process isexothermic and the adsorption heat is up to 38.4 kJ/mol. Withrespect to high efficiency, moderate pH requirement and minimizedsecond pollution, the tannin gel adsorbent exhibits a promisingpotential in the removal of lead from wastewater.
