Exploring Cacao Husk Waste: Surface Modification, Characterization, and its Potential for Removing Phosphate and Nitrate Ions

Abstract

Environmental pollution by phosphate and nitrate ions has become a serious problem. The innovation of cacao husk as an adsorbent and sustainable material can be a solution for absorbing phosphate and nitrate ions. Cocoa husk (CH) derived from the matured cocoa fruit's remaining pod material that often discarded as waste. The aim of this research is to develop an environmentally friendly and economical cacao husk (CH) based material for the absorption of phosphate and nitrate ions from aqueous solutions. CH surface modification is made by reacting the cationic polymer 2-[(methacryloyloxy)ethyl]trimethylammonium (META), into CH treatment (CH-T). Successful surface modification of CH-T with cationic polymers was confirmed to improve the surface properties for the removal of phosphate and nitrate ions. The surface charge morphology, structure, pore distribution and stability of the modified CH-T were investigated by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Branueur-Emmet-Teller (BET) and elemental analysis. 0.3 grams of CH-T modified with 75% cationic polymer with stirring at 70 rpm for 180 minutes at 50°C was reported as the best modification condition. Removal efficiencies of phosphate and nitrate ions increased after adding quaternary ammonium to CH-T to 96% and 93.4%, respectively. These results indicate that CH modification has prospective as a low-cost catalyst for wastewater treatment.