بررسی کارایی پامیس پودری در حذف سرب از محیط های آبی- مطالعه ایزوترم و سینتیک واکنش

Background and purpose: Lead is a toxic heavy metal that is considered major environmental contaminants and all its compounds are important in terms of toxicity in humans. So, the aim of this study was to _____the efficiency survey of pumice powder to lead removal from the aquatic environment. Material and Methods: In the beginning of this study, the powdered form of pumice was prepared, then the batch experiments were performed at room temperature in the variety of conditions including different contact times, various adsorbent dosages, pH=7, agitation periods=200 rpm and concentration of lead (50 mg/L). Obtained data were fitted to Langmuir and Freundlich isotherms and the pseudo first and second order and the intraparticle diffusion reaction kinetics. Results: The results showed that lead is most absorbed so its maximum removal was obtained 100%, Correlation coefficients indicate the following order to fit both isotherms: Freundlich and Langmuir for lead (R2=0.995, R2=9) respectively and second-order reaction kinetics. Also, the removal efficiency has significant difference by increasing the adsorbent dose and contact time (R2 >‍‍0.001). Conclusion: Note that the separation coefficient (RL) and adsorption intensity was obtained in the favorable range 1-0, so the pumice is the effective adsorbent for lead removal from the aquatic environment.