@article{scholars14983,
            year = {2021},
       publisher = {Materials China},
         journal = {Chinese Journal of Chemical Engineering},
           pages = {297--305},
            note = {cited By 8},
          volume = {33},
             doi = {10.1016/j.cjche.2020.08.027},
           title = {Optimization and evaluation of reduced graphene oxide hydrogel composite as a demulsifier for heavy crude oil-in-water emulsion},
        abstract = {The rising production of produced water from oilfields had been proven to bring detrimental environmental effects. In this study, an efficient, recyclable, and environmental-friendly reduced graphene oxide immobilized {\^I}?-Carrageenan hydrogel composite ({\^I}?CaGO) was fabricated as an alternative sorbent for crude oil-in-water demulsification. Polyethyleneimine (PEI) was employed to form a stable hydrogel composite. The conditions for the immobilization of graphene oxide (GO) on PEI-modified {\^I}?-Carrageenan ({\^I}?C) beads were optimized appropriately. An immobilization yield of 77 was attained at 2 PEI, 2 h immobilization activation time, and pH 6.5. Moreover, the synthesized {\^I}?CaGO is capable of demulsification with an average demulsification efficiency of 70. It was found that the demulsification efficiency increases with salinity and {\^I}?CaGO dosage, and it deteriorates under alkaline condition. These phenomena can be attributed to the interfacial interactions between {\^I}?CaGO and the emulsion. Furthermore, the {\^I}?CaGO can be recycled to use for up to six cycles without significant leaching and degradation. As such, the synthesized {\^I}?CaGO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water. {\^A}{\copyright} 2020 Chemical Industry and Engineering Society of China},
        keywords = {Alkalinity; Crude oil; Demulsification; Efficiency; Emulsification; Emulsions; Hydrogels; Produced Water; Reduced Graphene Oxide, Alkaline conditions; Demulsification efficiency; Environmental-friendly; Heavy crude oil; Hydrogel composites; Interfacial interaction; Kappa carrageenan; Polyethyleneimine, Graphene},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103935652&doi=10.1016\%2fj.cjche.2020.08.027&partnerID=40&md5=6598672857abc3e3cb74163448a2198d},
            issn = {10049541},
          author = {Fong, K. K. and Tan, I. S. and Foo, H. C. Y. and Lam, M. K. and Tiong, A. C. Y. and Lim, S.}
}