Total Dissolved Solids, Phenol, and Barium Removals from Oilfield Produced Water Using Kapok Fibers and Ultrafiltration Membrane

Oilfield-produced water treatment using raw Kapok fiber (RKF) and a modified surface of Kapok fiber followed by an ultrafiltration membrane was conducted to reduce total dissolved solids (TDS), phenol, and barium. Variables considered in the experiment were contact times (30, 60, 90 min.), the flow rate of samples (5, 6, and 7 L/min), and trans-membrane pressure of ultrafiltration membrane (0.25, 0.35, and 0.50 bar). Raw Kapok fiber and modified surface Kapok fiber were used to investigate the effect of Kapok fiber on total dissolved solids, phenol, and barium removals from produced water. The results showed that raw KF decreased the TDS, phenol, and barium by 51.81%, 62.63%, and 54.20%, respectively. Treatment of raw Kapok fiber column filtrate using ultrafiltration membranes (UF) showed the removal of TDS, barium, and phenol achieved 73.15%, 42.44%, and 79.45%, respectively, at a flow rate of 5 L/min, TMP of 0.25 bar, and contact time of 90 min. Modifying the Kapok fiber surface using sodium hydroxide solution (5 wt%) and hot water (98.5 °C) reduced the TDS, phenol, and barium to 57.32%, 65.83%, and 79.08%, respectively. Further, at the same operating condition, the modified surface of Kapok fiber followed by UF decreased 94.31% TDS, 84.20% phenol, and 56.23% barium, respectively. The results show that modification of the Kapok fiber surface followed by UF can be used to remove the TDS, phenol, and barium from produced water.