Adsorption of ibuprofen from aqueous solution by modified date palm biochar: Performance, optimization, and life cycle assessment

In this study, date palm biochar (DP) was modified through acidification with HCl (DPA), alkali treatment with NaOH (DPB), chitosan (chitosan-DP), metal loading with Fe₃O₄ (DPI) and acidification and metal loading with HCl + Fe₃O₄ (DPAI) to enhance ibuprofen (IBP) adsorption from wastewater. Optimization was done using Box-Behnken model-based response surface methodology. DPAI showed the highest IBP adsorption capacity (72.2 mg/g) surpassing DPA (71.5 mg/g), DPB (67.8 mg/g), DPI (67.81 mg/g), DP (65.7 mg/g) and Chitosan-DP (61.32 mg/g) under optimal conditions (pH - 2, concentration - 150 mg/L, time - 20 h). This was due to improved pore structure and increased adsorption sites. However, life cycle assessment revealed that DPAI had the highest environmental impact out of all the modified biochars with a Cumulative Energy Demand (CED) of 143.22 MJ/kg and a Global Warming Potential (GWP) of 10 kg CO₂eq. Sensitivity analysis suggested that transitioning to renewable energy sources could reduce GHG by 37.4 % and CED by 22.1 %. Additionally, reducing iron content can mitigate 22.1 % of GHG and 8.1 % of CED for DPAI. Nonetheless, DPAI still demonstrated effective adsorption rates after 2 cycles of regeneration study.