You are using an activated carbon to treat a water contaminated with phenol. the following freundlich isotherm parameters (qe = kf ce n ) were obtained from a phenol isotherm: kf = 28 and n= 0.35 (where ce is in mg phenol/ l water and qe is in mg phenol/ g carbon). in a completely mixed batch reactor (v = 2500 gallons) filled with 2000 gallons of wastewater, you want to reduce the phenol concentration from 10 mg/l to 0.5 mg/l. how much of the activated carbon should you add?