%0 Journal Article %T Removal of Calcium (Ca2+) Ion from Aqueous Solution by Chemically Activated Thuja Occidentalis Leaves Carbon (CATLC)-Application for Softening the Groundwater Samples %J Physical Chemistry Research %I Iranian Chemical Society %Z 2322-5521 %A Vaddi, Dhilleswararao %A Subbarao, Mushini Venkata %A Muralikrishna, M.P.S %D 2019 %\ 09/01/2019 %V 7 %N 3 %P 449-466 %! Removal of Calcium (Ca2+) Ion from Aqueous Solution by Chemically Activated Thuja Occidentalis Leaves Carbon (CATLC)-Application for Softening the Groundwater Samples %K Ca2+ removal %K Thuja Occidentalis leaves %K CATLC %K FTIR %K SEM %R 10.22036/pcr.2019.170974.1590 %X In this research paper, chemically activated Thuja Occidentalis leaves carbon (CATLC) is used as an adsorbent for the removal of calcium (Ca2+) ion from aqueous solution. CATLC is prepared and characterized by FTIR, SEM and EDX. The impact of pH, adsorbent dosage, contact period and initial concentration of Ca2+ on the adsorption performance of CATLC for Ca2+ removal are examined by batch studies. The results disclose that CATLC has a high potential to adsorb Ca2+ (91% removal) at pH 7.00. To know the equilibrium behaviour of Ca2+ adsorption, Freundlich and Langmuir models are investigated, and the data discloses that Langmuir model (maximum adsorption capacity ‘Qm’ obtained is of 51.28mg/g and R2= 0.9953) fits better than Freundlich model(R2 =0.8723). The Kinetic studies indicate that pseudo-second-order(R2= 0.9909) is the best fit rather than pseudo-first order, intra particle and Elovich models and chemisorptions are the rate-limiting steps for the Ca2+ adsorption using CATLC adsorbent. Regeneration studies showed that CATLC can be regenerated easily and reused for several adsorption cycles, with sodium chloride solution as a regenerating agent. The application of CATLC adsorbent is useful to reduce the hardness concentration in groundwater samples to meet the allowable limit according to WHO-2011 standards. %U https://www.physchemres.org/article_88260_3ede06505d2b86e1d04dc8e0c1ee487a.pdf