Adsorption Characteristics of Cu2+ onto Zeolite from Pharmaceutical Industrial Wastewater

The adsorption of Cu 2+ from pharmaceutical wastewater by zeolite was studied in a batch adsorption system. Factors influencing copper adsorption such as pH (1-5), adsorbent dosage (5-50 g/L) and contact time (20-600 min) were investigated. The equilibrium of adsorption process was established in about 480 min, while pH was 5 and adsorbent dosage was 30 g/L. After the adsorption equilibrium was achieved, the removal efficiency of Cu 2+ was above 99%. A comparison of the kinetic models on the overall adsorption rate showed that the adsorption system was best described by the pseudo second-order kinetics. The adsorption equilibrium data fit best with the Langmuir isotherm.