Multi-slice Ni-doped brochantite modified and polymer crosslinked cellulose paper with high wet stability and oil repellency for water disposal

Abstract

Cellulose paper (CP) is an environmentally-friendly and low-cost material, but its application in petrochemical water disposal is limited by poor wet stability and oil repellency. In this work, based on the crosslinking and low-temperature hydrothermal reaction, we report a novel CP material which is crosslinked by polyethyleneimine (PEI)-glutaraldehyde (GA)-cellulose and modified by Ni-doped brochantite crosslinked CP (NB-PCCP) for the removal of emulsified oils and dyes in wastewater. The crosslinking process enhances the wet strength of CP, and the formation of the multi-slice structure of Ni-doped brochantite on PCCP surface improves the oil repellency. Results show that NB-PCCP possesses outstanding oil-in-water emulsion separation performance with high oil rejection of 99.9%, the Young's modulus of NB-PCCP is quadruple that of untreated CP in wet conditions, indicating improved wet stability in practice application. NB-PCCP also displays excellent removal performance for dyes due to the existence of high-density hydroxyl radicals, as well as excellent acid/alkali resistance. The research on CP provides significant guidance for the design of cellulose-based material with multi-slice structure as well as high wet strength and oil repellency for the purification of wastewater.