Removal of Lead and Cadmium by Coral Limestone Granules of Aquatic Solutions

Due to the increasing use of the adsorption process to remove pollutants in the environment, choosing a suitable material from technical and economical aspects as catchy has been a major concern of researchers in this field. The aim of this study was to evaluate the efficiency of coral limestone granules to remove metals cadmium and lead in the aquatic solutions. This study was conducted in a laboratory scale. During the first stages some coral limestone with numerous granules were prepared from the 30 mesh metal removal efficiency under different conditions and changing the effective factors, including pH; contact time and amount of adsorbent was determined. Aabsorption isotherms of metal ions on the adsorbent according to the desired test Langmuir and Freundlich isotherm models were evaluated. This study showed that maximum adsorption capacity of cadmium and lead on calcareous coral granules in optimum condition is 370/3 and 14/77 mg /L respectively. The removal efficiency of metals contact time, amount of adsorbent and pH was directly related to the most appropriate pH for the removal of metals is studied pH = 10 in the best model isotherms adsorb the cadmium model of Langmuir (R2 = 0/9891) and for the lead model Freundlich (R2 = 0/9909) were determined. Due to good removal efficiency, low cost production process and lack of environmentally harmful substances, this material can be used to remove cadmium and lead from the Industrial Wastewater Treatment. Analyze data and determine correlations between variables using regression analysis Non-parametric Spearman showed no significant correlation between efficiency and the variables there.