ultrathin graphitic carbon nitride nanosheet as highly effective adsorbent for calcium ion: adsorption kinetics and equilibrium studies

ultrathin graphitic carbon nitride (g-c₃n₄) nanosheets, due to their interesting two-dimensional graphenelike structure and unique physicochemical properties, have attracted great research attention recently. here, we develop a new approach to prepare ultrathin g-c₃n₄ nanosheets by sonication-exfoliation of bulk g-c₃n₄. calcium is an essential macronutrient required for healthy human life. it is abundantly present in water. efficiency of ultrathin graphitic carbon nitride nanosheet in removal of calcium is not known. hence, the present work analysed adsorption kinetics of calcium from aqueous solution by using ultrathin graphitic carbon nitride nanosheet in batch culture methods. the effect of initial calcium concentration, temperature, and adsorbent mass on calcium removal was tested. the process of calcium adsorption followed pseudo second-order rate expression and obeyed the langmuir’s model with high correlation coefficient. the results indicate that ultrathin graphitic carbon nitride nanosheet is a potential adsorbent for calcium, as evident by its high calcium adsorption value under optimal culture conditions.