Optimization of the Forward‐Osmosis Performance with a Low‐Concentration Draw Solution Using Response Surface Modeling

Forward osmosis (FO) has recently gained interest in wastewater treatment and seawater and brackish groundwater desalination. Response surface methodology (RSM) was used for the prediction and optimization of the FO process using a low‐concentration draw solution (DS). The process variables were the feed solution (FS) temperature, the DS concentration, and the FS concentration. These variables were subjected to regression models and had R2 values > 0.9. The FS temperature had a negative impact on the weight transfer from the DS, while the FS and DS concentrations had a direct correlation with the performance. At an FS temperature of 29 °C, the DS at 13 986 mg L−1 and the FS at 1702 mg L−1 produced the best results, thereby lowering the DS regeneration costs. Under this condition, the models were experimentally validated, confirming the predictive ability of the models.