{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T02:55:50Z","timestamp":1790564150840,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T00:00:00Z","timestamp":1776384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cTianshan Talents\u201d Foundation","award":["2023TSYCJC0065"],"award-info":[{"award-number":["2023TSYCJC0065"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52360003"],"award-info":[{"award-number":["52360003"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52360003"],"award-info":[{"award-number":["52360003"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Karamay innovative environment construction plan (innovative talents) project","award":["2024hjcxrc0088"],"award-info":[{"award-number":["2024hjcxrc0088"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>The produced water from the No. 1 Oil Production Plant of Xinjiang Oilfield is rich in divalent ions, including Ca2+, Mg2+, and SO42\u2212, leading to extremely high scaling tendency that fails to meet the reinjection standard. Therefore, highly efficient water softening technology is urgently required for such wastewater treatment. In this study, a novel negatively charged nanofiltration (NF) membrane was fabricated via interfacial polymerization using 2-carboxypiperazine and trimesoyl chloride as monomers. The membrane was systematically characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR), and its rejection performance was investigated under various conditions. Results show that the maximum rejection rates of the NF membrane reached 99% for SO42\u2212, 81% for Ca2+, and 94% for Mg2+, respectively. With increasing ion concentration, the removal efficiencies of Ca2+ and Mg2+ decreased, while that of SO42\u2212 increased slightly. Higher operating pressure significantly enhanced both ion removal and membrane flux, which was mainly attributed to the synergistic effects of Donnan electrostatic exclusion, membrane surface adsorption, and mass transfer resistance. When applied to treat real produced water from the No. 1 Oil Production Plant, the membrane achieved 100% removal of SO42\u2212, and 91% and 95% removal of Ca2+ and Mg2+, respectively. The scaling tendency of the treated effluent was completely eliminated. This work provides theoretical and technical support for the engineering application of nanofiltration technology in oilfield wastewater treatment.<\/jats:p>","DOI":"10.3390\/membranes16040151","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T11:53:46Z","timestamp":1776426826000},"page":"151","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Preparation of a Novel Nanofiltration Membrane and Study of Its Process for Removing Divalent Ions from Xinjiang Oilfield Wastewater"],"prefix":"10.3390","volume":"16","author":[{"given":"Zongneng","family":"Zheng","sequence":"first","affiliation":[{"name":"School of Petroleum Engineering, Karamay Vocational & Technical College, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Di","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Petroleum Engineering, Karamay Vocational & Technical College, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahang","family":"Wan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Heavy Oil Processing, China University of Petroleum (Beijing) at Karamay, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianping","family":"Li","sequence":"additional","affiliation":[{"name":"Karamay Xinkeao Petroleum Technological Co., Ltd., Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Karamay Xinkeao Petroleum Technological Co., Ltd., Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanxin","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Heavy Oil Processing, China University of Petroleum (Beijing) at Karamay, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haiyi","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Heavy Oil Processing, China University of Petroleum (Beijing) at Karamay, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1943-5395","authenticated-orcid":false,"given":"Junwei","family":"Hou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Heavy Oil Processing, China University of Petroleum (Beijing) at Karamay, Karamay 834000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,17]]},"reference":[{"key":"ref_1","unstructured":"(1996). Integrated Wastewater Discharge Standard (Standard No. GB 8978-1996)."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Guo, L., Xie, Y., Sun, W., Xu, Y., and Sun, Y. (2023). Research Progress of High-Salinity Wastewater Treatment Technology. Water, 15.","DOI":"10.3390\/w15040684"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Haq, I., Kalamdhad, A.S., and Khwairakpam, M. (2024). Advancement in Solid Waste Management and Treatment, Springer Nature. Available online: https:\/\/www.springerprofessional.de\/advancement-in-solid-waste-management-and-treatment\/50055330.","DOI":"10.1007\/978-3-031-64873-1"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"105727","DOI":"10.1016\/j.resconrec.2021.105727","article-title":"Solid Waste Management in China: Policy and Driving Factors in 2004\u20132019","volume":"173","author":"Guo","year":"2021","journal-title":"Resour. Conserv. Recycl."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3248","DOI":"10.1038\/s41598-023-29956-4","article-title":"Removal of Cu2+, Fe2+ and SO42\u2212 Ions from Industrial Wastewater by Ion Exchange Resins Contained in a Rotating Perforated Cylindrical Basket of Different Heights|Scientific Reports","volume":"13","author":"Zakaria","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"116615","DOI":"10.1016\/j.desal.2023.116615","article-title":"Sulphate Removal from Aqueous Solutions: State-of-the-Art Technologies and Future Research Trends","volume":"558","author":"Chatla","year":"2023","journal-title":"Desalination"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/S1093-0191(02)00128-4","article-title":"Graphical Strategies for Design of Evaporation Crystallization Networks for Environmental Wastewater Applications","volume":"8","author":"Parthasarathy","year":"2004","journal-title":"Adv. Environ. Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1007\/s13201-022-01748-7","article-title":"Sulfate Removal from Chemical Industries\u2019 Wastewater Using Ettringite Precipitation Process with Recovery of Al(OH)3","volume":"12","author":"Zahedi","year":"2022","journal-title":"Appl. Water Sci."},{"key":"ref_9","first-page":"15","article-title":"Current situation and technical research direction of CO2 flooding injection-production technology in Changqing oilfield","volume":"42","author":"Yu","year":"2023","journal-title":"Petrochem. Ind. Appl."},{"key":"ref_10","first-page":"409","article-title":"Study on Demulsification Technology of Heavy Oil Blended in Xinjiang Oilfield","volume":"11","author":"Zou","year":"2023","journal-title":"Prossess"},{"key":"ref_11","first-page":"1","article-title":"Study on the Removal of Calcium and Magnesium Ions from Coal Gasification Slag Water by Carbon Dioxide","volume":"39","author":"Zhu","year":"2025","journal-title":"Chem. Ind. Times"},{"key":"ref_12","first-page":"73","article-title":"Research on the resource utilization of MVC concentrated water, softening regeneration wastewater and waste heat","volume":"14","author":"Nie","year":"2024","journal-title":"Energy Conserv. Meas. Pet. Petrochem. Ind."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Yuliwati, E., Ismail, A.F., Othman, M.H.D., and Shirazi, M.M.A. (2022). Critical Flux and Fouling Analysis of PVDF-Mixed Matrix Membranes for Reclamation of Refinery-Produced Wastewater: Effect of Mixed Liquor Suspended Solids Concentration and Aeration. Membranes, 12.","DOI":"10.3390\/membranes12020161"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"142266","DOI":"10.1016\/j.jclepro.2024.142266","article-title":"Strategies for Biological Treatment of Waste Water: A Critical Review","volume":"454","author":"Singh","year":"2024","journal-title":"J. Clean. Prod."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/S0015-1882(15)30089-6","article-title":"Seawater Sulfate Removal with Nanofiltration","volume":"52","year":"2015","journal-title":"Filtr. + Sep."},{"key":"ref_16","first-page":"94","article-title":"Effect of polyetheramine on microstructure and properties of selected layer of CPVC composite nanofiltration membrane","volume":"45","author":"Chen","year":"2025","journal-title":"Mod. Chem. Ind."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1016\/j.desal.2006.03.266","article-title":"Ion Transport through Nanofiltration Membranes: The Steric, Electric and Dielectric Exclusion Model","volume":"200","author":"Szymczyk","year":"2006","journal-title":"Desalination"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"15874","DOI":"10.1021\/acs.est.4c07510","article-title":"The Hidden Role of the Dielectric Effect in Nanofiltration: A Novel Perspective to Unravel New Ion Separation Mechanisms","volume":"58","author":"Zhai","year":"2024","journal-title":"Environ. Sci. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"122412","DOI":"10.1016\/j.memsci.2024.122412","article-title":"Comparative Analysis of Polyamide Nanofiltration Membranes Resistance to Different Acids: Insights from Experiments and Density Functional Theory Simulations","volume":"694","author":"Gao","year":"2024","journal-title":"J. Membr. Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"125182","DOI":"10.1016\/j.memsci.2026.125182","article-title":"Positively charged polyamide nanofiltration membrane via grafting a bis-pyridinium molecule for high-efficiency Mg2+\/Li+ separation","volume":"743","author":"Yi","year":"2026","journal-title":"J. Membr. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"151334","DOI":"10.1016\/j.scitotenv.2021.151334","article-title":"Adsorption Isotherm Models: A Comprehensive and Systematic Review (2010\u22122020)","volume":"812","author":"Ghalandari","year":"2022","journal-title":"Sci. Total Environ."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"120057","DOI":"10.1016\/j.memsci.2021.120057","article-title":"Molecular Insights into Charged Nanofiltration Membranes: Structure, Water Transport, and Water Diffusion","volume":"644","author":"Liu","year":"2022","journal-title":"J. Membr. Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.memsci.2004.05.022","article-title":"Nanofiltration of Multi-Component Feeds. Interactions between Neutral and Charged Components and Their Effect on Retention","volume":"247","author":"Bargeman","year":"2005","journal-title":"J. Membr. Sci."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"5174","DOI":"10.1021\/acs.est.3c10195","article-title":"Polyamide Membranes with Tunable Surface Charge Induced by Dipole-Dipole Interaction for Selective Ion Separation","volume":"58","author":"Zhao","year":"2024","journal-title":"Envrion. Sci. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"129169","DOI":"10.1016\/j.seppur.2024.129169","article-title":"A Review of the Nanofiltration Membrane for Magnesium and Lithium Separation from Salt-Lake Brine","volume":"354","author":"Zhang","year":"2025","journal-title":"Sep. Purif. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3351","DOI":"10.1016\/j.matt.2024.07.006","article-title":"Enhancement of Ion Selectivity and Permeability in Two-Dimensional Material Membranes","volume":"7","author":"Luo","year":"2024","journal-title":"Matter"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"106","DOI":"10.1016\/j.desal.2011.04.010","article-title":"Salts Retention by Nanofiltration Membranes: Physicochemical and Hydrodynamic Approaches and Modeling","volume":"277","author":"Kelewou","year":"2011","journal-title":"Desalination"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1016\/j.memsci.2015.03.039","article-title":"The Effect of Membrane Characteristics on Nanofiltration Membrane Performance during Processing of Practically Saturated Salt Solutions","volume":"485","author":"Bargeman","year":"2015","journal-title":"J. Membr. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/j.memsci.2004.03.004","article-title":"Effect of Concentration Polarisation and Osmotic Pressure on Flux in Organic Solvent Nanofiltration","volume":"236","author":"Peeva","year":"2004","journal-title":"J. Membr. Sci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1016\/j.memsci.2014.08.045","article-title":"Nanofiltration Separation of Polyvalent and Monovalent Anions in Desalination Brines","volume":"473","author":"Urtiaga","year":"2015","journal-title":"J. Membr. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"492","DOI":"10.1007\/s11705-011-1143-7","article-title":"Effects of Operating Conditions on Membrane Charge Property and Nanofiltration","volume":"5","author":"Xu","year":"2011","journal-title":"Front. Chem. Sci. Eng."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1016\/j.cej.2018.10.087","article-title":"Low Operating Pressure Nanofiltration Membrane with Functionalized Natural Nanoclay as Antifouling and Flux Promoting Agent","volume":"358","author":"Aruchamy","year":"2019","journal-title":"Chem. Eng. J."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"118380","DOI":"10.1016\/j.memsci.2020.118380","article-title":"Nanofiltration of Solutions Containing Organic and Inorganic Salts: Relationship between Feed and Permeate Proportions","volume":"613","author":"Zhu","year":"2020","journal-title":"J. Membr. Sci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"118645","DOI":"10.1016\/j.memsci.2020.118645","article-title":"Regulating the Morphology of Nanofiltration Membrane by Thermally Induced Inorganic Salt Crystals for Efficient Water Purification","volume":"617","author":"Liu","year":"2021","journal-title":"J. Membr. Sci."}],"container-title":["Membranes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0375\/16\/4\/151\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T12:14:31Z","timestamp":1776428071000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0375\/16\/4\/151"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,17]]},"references-count":34,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["membranes16040151"],"URL":"https:\/\/doi.org\/10.3390\/membranes16040151","relation":{},"ISSN":["2077-0375"],"issn-type":[{"value":"2077-0375","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,17]]}}}