{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T22:40:18Z","timestamp":1784673618737,"version":"3.55.0"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T00:00:00Z","timestamp":1777420800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Romanian Ministry of Research, Innovation, and Digitalization","award":["3N\/2022"],"award-info":[{"award-number":["3N\/2022"]}]},{"name":"Romanian Ministry of Research, Innovation, and Digitalization","award":["PN 23 22 03 01"],"award-info":[{"award-number":["PN 23 22 03 01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Pharmaceutical residues continue to increasingly contaminate water systems at a global level, and conventional wastewater treatment plants are unable to completely remove these emergent compounds. This study investigates the benzocaine adsorption from aqueous solutions onto Amberlite XAD-7 (X7) resin, with emphasis on quantitative performance metrics and mechanistic understanding. Adsorption occurred rapidly, reaching equilibrium within 60 min, with a maximum adsorption capacity (Qe) of 140 mg\/g and a Langmuir monolayer capacity of 147 mg\/g. Experimental parameters strongly influenced X7 performance: resin dosage (0.01\u20130.05 g) and agitation speed (25\u2013200 rpm) enhanced removal efficiency from 10% to 99.9%, while pH variation (5\u20139) had a negligible effect, confirming a predominantly hydrophobic, non-ionic adsorption mechanism. Equilibrium data are best described by the Langmuir model (R2 = 0.9920, b = 5.2 L\/mg, RL = 0.0003), indicating highly favorable monolayer adsorption, while kinetic behavior is described by the pseudo-second-order (PSO) model. FTIR-ATR analysis confirms benzocaine retention through characteristic shifts in aromatic, amine, and ester bands. TG\/DSC measurements prove the thermal stability of X7 and the incorporation of benzocaine within the polymeric matrix. Desorption efficiencies ranged from 40% (NaOH) to 97% (HCl-ethanol mixture), demonstrating that X7 was regenerated under the tested conditions with a single cycle. Overall, X7 exhibits high capacity, robustness, and recyclability, highlighting its strong potential for efficient benzocaine removal from contaminated wastewater.<\/jats:p>","DOI":"10.3390\/polym18091082","type":"journal-article","created":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T12:31:56Z","timestamp":1777465916000},"page":"1082","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Resin-Based Technology for the Efficient Removal of Benzocaine from Wastewaters"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9145-7502","authenticated-orcid":false,"given":"Nicoleta Mirela","family":"Marin","sequence":"first","affiliation":[{"name":"National Research and Development Institute for Industrial Ecology ECOIND, Street Podu Dambovitei No. 57-73, District 6, 060652 Bucharest, Romania"},{"name":"Department of Analytical and Physical Chemistry, University of Bucharest, 4-12 Regina Elisabeta Bd., 030018 Bucharest, Romania"},{"name":"Department of Oxide Materials Science and Engineering, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toma","family":"Galaon","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Industrial Ecology ECOIND, Street Podu Dambovitei No. 57-73, District 6, 060652 Bucharest, Romania"},{"name":"Department of Analytical and Physical Chemistry, University of Bucharest, 4-12 Regina Elisabeta Bd., 030018 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4928-8159","authenticated-orcid":false,"given":"Adriana Mariana","family":"Bor\u0219","sequence":"additional","affiliation":[{"name":"National Institute for R&D for Optoelectronics-Subsidiary, Research Institute for Hydraulics and Pneumatics\u2014INOE 2000-IHP, 040558 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3371-4136","authenticated-orcid":false,"given":"Ludmila","family":"Motelica","sequence":"additional","affiliation":[{"name":"National Centre for Micro- and Nanomaterials, National University of Science and Technology Politehnica Bucharest, 313 Independence Boulevard, 060042 Bucharest, Romania"},{"name":"National Centre for Food Safety, National University of Science and Technology Politehnica Bucharest, 313 Independence Boulevard, 060042 Bucharest, Romania"},{"name":"Academy of Romanian Scientists, 3 Ilfov St., 050045 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8145-1094","authenticated-orcid":false,"given":"Ovidiu","family":"Oprea","sequence":"additional","affiliation":[{"name":"National Centre for Micro- and Nanomaterials, National University of Science and Technology Politehnica Bucharest, 313 Independence Boulevard, 060042 Bucharest, Romania"},{"name":"National Centre for Food Safety, National University of Science and Technology Politehnica Bucharest, 313 Independence Boulevard, 060042 Bucharest, Romania"},{"name":"Academy of Romanian Scientists, 3 Ilfov St., 050045 Bucharest, Romania"},{"name":"Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu St., 011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"138241","DOI":"10.1016\/j.chemosphere.2023.138241","article-title":"Insight into the adsorptive removal of ibuprofen using porous carbonaceous materials: A review","volume":"323","author":"Ayati","year":"2023","journal-title":"Chemosphere"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"121752","DOI":"10.1016\/j.envres.2025.121752","article-title":"Occurrence and removal of pharmaceuticals in hospital wastewater and the contribution to wastewater treatment plants","volume":"279","author":"Tao","year":"2025","journal-title":"Environ. 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