Towards effective recovery of humate as green fertilizer from landfill leachate concentrate by electro-neutral nanofiltration membrane

Under the environmental sustainability concept, landfill leachate concentrate can be up-cycled as a useful resource. Practical strategy for effective management of landfill leachate concentrate is to recover the existing humate as fertil-izer purpose for plant growth. Herein, we designed an electro-neutral nanofiltration membrane to separate the humate and inorganic salts for achieving a sufficient humate recovery from leachate concentrate. The electro-neutral nanofiltration membrane yielded a high retention of humate (96.54 %) with an extremely low salt rejection (3.47 %), tremendously outperforming the state-of-the-art nanofiltration membranes and exhibiting superior promise in fractionation of humate and inorganic salts. With implementation of the pressure-driven concentration process, the electro-neutral nanoltration membrane enriched the humate from 1756 to 51,466 mg & BULL;L-1 at a fold of 32.6, enabling 90.0 % humate recovery and 96.4 % desalination efciency from landll leachate concentrate. Furthermore, the recovered humate not only exerted no phytotoxicity, but also signicantly promoted the metabolism of red bean plants, serving as an effective green fertilizer. The study provides a conceptual and technical platform using high-performance electro-neutral nanoltration membranes to extract the humate as a promising nutrient for fertilizer application, in view of sustainable landll leachate concentrate treatment.

Automated summary

Under the concept of environmental sustainability, landfill leachate concentrate can be used as a valuable resource. The electro-neutral nanofiltration membrane designed in this study achieved a high retention of humate (96.54%) with a low salt rejection (3.47%), outperforming state-of-the-art membranes and showing promise in fractionation of humate and inorganic salts.