OPTIMIZATION OF CRUDE OIL PRODUCED WATER TREATMENT USING A BLEND OF ACTIVATED CARBON FROM COCONUT SHELLS AND SAW DUST

Coconut shells and sawdust were used for the preparation of low-cost adsorbents using activated carbon for the treatment of produced water. Both materials were subjected to carbonization and chemical activation and were characterized using SEM and EDS. Among the two, CSAC had a more developed pore structure, yet higher carbon purity. SDAC on the other hand contained more mineral residues but has less defined pore geometry. Water quality measurement indicated that improvements in water quality were pronounced with treatment: Initial TDS concentration of 67 ppm was lowered to between 13 and 17 ppm in the most efficient experimental runs, the Total Petroleum Hydrocarbons (TPH) concentration ranging from 19.43 mg/L to as low as 1.71-3.43 mg/L. Response Surface Methodology for optimization suggested that the best treatment condition would be 6.43961 g/L CSAC, 5.88225 g/L SDAC, and an adsorption time of 39.5244 minutes for 80.64% TPH removal and 64.4872% TDS removal. Even though CSAC individually achieved the lowest TDS, EC, and TPH value in different runs, ANOVA results indicated that SDAC showed the highest consistency and statistically reliable performance among treatments. Both adsorbents, however, showed that they were effective and sustainable in the purification of produced water, with SDAC being statistically better while CSAC presented the highest efficiency in terms of single-run. Such findings revealed the possibility of making locally available agricultural wastes into affordable eco-friendly alternatives to commercial activated carbons.