Optimization of complex conditions by response surface methodology for APAM-oil/water emulsion removal from aqua solutions using nano-sized TiO_2/Al_2O_3 PVDF ultrafiltration membrane

摘要

This paper studies the cumulative effect of various parameters, namely anionic polyacrylamide (APAM) concentration, oil concentration, pH, trans-membrane pressure (TMP), and total dissolved solid (TDS), and obtains optimal parameters for the minimum relative flux (J/J_0) declining in aqueous solutions with response surface methodology (RSM). In order to analyze the mutual interaction and optimal values of parameters affecting ultrafiltration, a central composite rotatable design (CCRD), one method of RSM, was employed. The analysis of variance (AN0VA) of the cubic polynomial model demonstrated that this model was highly significant and reliable. The results show that the effect of APAM and oil on J/J_0 has an inverse trend with pH value increasing. Moreover, the mutual interaction of initial APAM (oil) concentration (C_(APAM(oil)) and PH (TMP) were negligible, while the mutual interaction of C_(apam) and C_(oil) has an obvious effect, i.e. the effect of initial feed C_(apam) became more important at higher values of initial feed C_(oil). and the J/J_0 was only about 4%. The favorable operate conditions in this ultrafiltration process were at low C_(apam). C_(oil), pH, and TMP, which agreed with the conclusions of many authors, while considering water production, C_(apam) and C_(oil) < 50 mg/L, pH < 4, and TMP < 0.075 MPa could be accepted.