{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T16:55:36Z","timestamp":1769532936613,"version":"3.49.0"},"reference-count":53,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,6]],"date-time":"2020-12-06T00:00:00Z","timestamp":1607212800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MCTES","award":["UID\/QUI\/50006\/2019"],"award-info":[{"award-number":["UID\/QUI\/50006\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Membranes"],"abstract":"<jats:p>Industrial adoption of nanofiltration (NF) for treatment of low-pH wastewater is hindered by the limited membrane lifetime at strongly acidic conditions. In this study, the electroplating wastewater (EPWW) filtration performance of a novel pH-stable NF membrane is compared against a commercial NF membrane and a reverse osmosis (RO) membrane. The presented membrane is relatively hydrophobic and has its isoelectric point (IEP) at pH 4.1, with a high and positive zeta potential of +10 mV at pH 3. A novel method was developed to determine the molecular weight cut-off (MWCO) at a pH of 2, with a finding that the membrane maintains the same MWCO (~500 Da) as under neutral pH operating conditions, whereas the commercial membrane significantly increases it. In crossflow filtration experiments with simulated EPWW, rejections above 75% are observed for all heavy metals (compared to only 30% of the commercial membrane), while keeping the same pH in the feed and permeate. Despite the relatively lower permeance of the prepared membrane (~1 L\/(m2\u00b7h\u00b7bar) versus ~4 L\/(m2\u00b7h\u00b7bar) of the commercial membrane), its high heavy metals rejection coupled with a very low acid rejection makes it suitable for acid recovery applications.<\/jats:p>","DOI":"10.3390\/membranes10120399","type":"journal-article","created":{"date-parts":[[2020,12,6]],"date-time":"2020-12-06T22:27:12Z","timestamp":1607293632000},"page":"399","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Treatment of Electroplating Wastewater Using NF pH-Stable Membranes: Characterization and Application"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2600-3595","authenticated-orcid":false,"given":"Ignacio","family":"Hegoburu","sequence":"first","affiliation":[{"name":"Associated Laboratory for Green Chemistry\u2014Clean Technologies and Processes (LAQV), REQUIMTE, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"given":"Karina Listiarini","family":"Zedda","sequence":"additional","affiliation":[{"name":"LANXESS\u2014IAB Ionenaustauscher GmbH Bitterfeld, 06803 Bitterfeld-Wolfen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9446-0897","authenticated-orcid":false,"given":"Svetlozar","family":"Velizarov","sequence":"additional","affiliation":[{"name":"Associated Laboratory for Green Chemistry\u2014Clean Technologies and Processes (LAQV), REQUIMTE, Chemistry Department, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/j.desal.2014.10.043","article-title":"Nanofiltration membranes review: Recent advances and future prospects","volume":"356","author":"Mohammad","year":"2015","journal-title":"Desalination"},{"key":"ref_2","unstructured":"Sch\u00e4fer, A.I., Fane, A.G., and Waite, T.D. 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