Inverse omosis elimination rate is high compared to nanofiltration. The concentration of certain metals in the the permeates of domestic wastewater are lower to the WHO standard, while in the industrial water permeates, it remains above the WHO standard, hence the need to prepare a low cost membrane to remove these metals in the permeate according to the WHO standard.
Kapepula Lumami, V., & et al. (2021). Evaluation of commercial ro and nf membranes, used for the release of heavy metals in wastewater. https://hdl.handle.net/2078.5/110155