KINETIC EVALUATION OF CASSAVA MASH BIOCARRIER-ENHANCED BIOREMEDIATION OF CRUDE OIL-CONTAMINATED WATER

Abstract

This study evaluated the kinetics of bioremediation of crude oil-polluted water using cassava mash as an organic biocarrier enhanced with Aspergillus niger fungus. The cassava mash was characterized to determine its chemical composition and nutrient content supporting microbial activity. Proximate analysis revealed that the biocarrier contained significant macro- and micronutrients including 75.42% carbon, 5.56% nitrogen, 19.75% phosphorus, 8.92% protein, and 15.66% cellulose. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of functional groups such as hydroxyl, aliphatic, carboxylic, aromatic, and ester compounds that facilitate microbial attachment and metabolism Bioremediation experiments were conducted under controlled conditions (298–306 K) using Aspergillus niger at 1×10⁶ CFU/mL. The rate of Total Petroleum Hydrocarbon (TPH) removal increased with temperature, showing maximum degradation efficiency at 304 K. Kinetic modeling demonstrated that TPH degradation followed both first-order and second-order reaction mechanisms. For cassava mash, the first-order rate constant (k₁) ranged from 0.0126 to 0.035 day⁻¹ with R² values between 0.85 and 0.91, while the second-order rate constant (k2) ranged from 0.0001 to 0.0005 day⁻¹ with R² > 0.80, indicating strong model conformity. The results demonstrate that cassava mash is rich in essential nutrients that enhance microbial activity, leading to efficient hydrocarbon degradation.