Removal of biphenyl and phenol from landfill leachate using groundnut shell biochar

Polluted wastewater with biphenyl and phenol represents a possible danger to human health, the environment and a major problem to the management of water. This study examined the ability of groundnut shell biochar to remove biphenyl and phenol from landfill leachate. Batch adsorption experiments of biphenyl and phenol with groundnut shell biochar were conducted to determine the effects of biochar dosage, contact times and different temperatures. The adsorption efficiency of groundnut shells biochar for the biphenyl ranged from 63.33 to 73.33 % at 15 min, 40.00 to 53.33 % at 30 min and 46.67 to 66.67 % at 45 min at a temperature of 30 ℃. The removal efficiency of up to 73.33 % and 71.65 % was obtained for biphenyl and phenol, respectively, at adsorption conditions of 30 ℃ and 35 ℃ with contact times of 15, 30 and 45 minutes. The study found that increasing the adsorbent dosage increases the removal efficiency of biphenyl and phenol. Groundnut shell biochar has good affinity for biphenyl and phenol in the landfill leachate. The Freundlich model is the best fit for the biphenyl and phenol adsorption onto groundnut shell biochar based on the KF, N and R2 values. The adsorption of biphenyl and phenol is effective, chemical in nature, and the surface of the groundnut shell biochar is heterogeneous and possesses a great affinity for biphenyl and phenol in the landfill leachate. Groundnut shells can be used for making biochar for biphenyl and phenol from the landfill leachate or wastewater and aqueous environment.