CIP and NOR removal percentages of prepared carbon as a function of pH (2–12) at different initial concentrations is shown Fig. 3a. For both compounds, adsorption initially increases with increasing pH and reached a plateau then decreased at higher pH. An increase in pH from 2 to 9 at 0.75 g/l dose, 20 mg/l initial CIP concentration and 90 min contact time leads to an increase in CIP removal percentage from 89.611% to 96.12%. While, the increase in pH from 2 to 5 at 0.50 g/l dose, 20 mg/l initial NOR concentration and 60 min contact time causes an increase in NOR removal percentage from 94.78% to 98.12%. Therefore, the values of 9 and 5 are considered to be the best pH for maximum removal of CIP and NOR, respectively.