Response surface methodology approach for the optimisation of adsorption of hydrolysed polyacrylamide from polymer-flooding wastewater onto steel slag: a good option of waste mitigation

Abstract

Wastewater produced from polymer flooding in oil production features high viscosity and chemical oxygen demand because of the residue of high-concentration polymer hydrolysed polyacrylamide (HPAM). In this study, steel slag, a waste from steel manufacturing, was studied as a low-cost adsorbent for HPAM in wastewater. Optimisation of HPAM adsorption by steel slag was performed with a central composite design under response surface methodology (RSM). Results showed that the maximum removal efficiency of 89.31% was obtained at an adsorbent dosage of 105.2 g/L, contact time of 95.4 min and pH of 5.6. These data were strongly correlated with the experimental values of the RSM model. Single and interactive effect analysis showed that HPAM removal efficiency increased with increasing adsorbent dosage and contact time. Efficiency increased when pH was increased from 2.6 to 5.6 and subsequently decreased from 5.6 to 9.3. It was observed that removal efficiency significantly increased (from 0% to 86.1%) at the initial stage (from 0 min to 60 min) and increased gradually after 60 min with an adsorbent dosage of 105.2 g/L, pH of 5.6. The adsorption kinetics was well correlated with the pseudo-second-order equation. Removal of HPAM from the studied water samples indicated that steel slag can be utilised for the pre-treatment of polymer-flooding wastewater.

Optimization and Modelling Using the Response Surface Methodology for Methylene Blue Removal by Electrocoagulation/Hazelnut Shell Adsorption Coupling in a Batch System

“…This result may be attributed to the abundantly available unsaturated sites on the surface of the adsorbent at the beginning of the reaction time. The adsorption became slow with a further increase in time due to the decrease in the number of active surface area [31].…”

Study on low temperature plasma combined with AC/Mn + TiO2–Al2O3 catalytic treatment of sewage-containing polyacrylamide

“…The existing main treatment methods are flawed (Hu et al 2006;Al Momani & Örmeci 2014;Farrokhpay & Filippov 2017;Ma et al 2017). The physical method removes PAM from wastewater through adsorption, extraction, membrane separation and other physical functions, but this method only transfers pollutants, which is difficult to destroy the internal structure of PAM and cannot eradicate pollutants (Zhu et al 2017;Wei et al 2018;Crema et al 2020). The chemical method uses a large number of chemical reagents to carry out the chemical decomposition reaction with PAM to achieve sewage purification.…”

Multivariate Parameter Optimization of PAM Wastewater Treatment by Ti/Ir–Ta Electrocatalysis via the Box-Behnken Design

“…Therefore, how to remove the residual PAM in wastewater effectively has become a key concern in the field of environment. At present, the main methods for treating polymer-containing wastewater are physical treatment [5], biodegradation [6][7][8], chemical degradation [9][10] and combination method [11]. The use of an electrochemical method for the degradation of wastewater is characterized by many advantages, including flexible operation, simple equipment, clean and environmental protection, no secondary pollution, fast degradation reaction speed, mild reaction conditions and evident degradation effect of PAM.…”