In the present study, adsorption of Pb2 + from aqueous solutions onto prepared activated carbon using Persian mesquite grain was studied. Several techniques and methodologies such as, proximate analysis, N2 adsorption–desorption isotherms, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD), Thermo gravimetric analysis TGA/DTA, elemental analysis(CHNS), Boehm titration, and point of zero charge (pHpzc) have been used to determine physicochemical properties of raw material and activated carbon. Through the XRD, SEM, TGA/DTA, elemental and FT-IR analysis, it could be observed that significant changes in porosity occurred after the activation process. The N2 adsorption results demonstrated that the activated carbon is composed mainly of microspores (63.8%), presenting high BET surface area of 1243 (m2·g− 1) and exhibit Type I isotherm. According to Boehm titration, surface of activated carbon includes a majority of acidic groups which is in agreement with the obtained pHpzc value of 3.73. The maximum adsorption capacity for Pb2 + is much higher than the other granular and powdered activated carbons. High efficiency in Pb2 + removal indicates that activated Persian mesquite grain could be successfully used as an excellent adsorbent in water purification.
