{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T02:33:34Z","timestamp":1789439614290,"version":"build-2803163510"},"reference-count":60,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,10,3]],"date-time":"2021-10-03T00:00:00Z","timestamp":1633219200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The study of new useful, efficient and selective structures for the palladium ions\u2019 recovery has led to the development of a new series of macromolecules. Thus, this study presents a comparative behavior of two crown benzene ethers that modify the magnesium silicate surface used as adsorbent for palladium. These crown ethers are dibenzo18-crown-6 (DB18C6) and dibenzo 30-crown-10 (DB30C10). The obtained materials were characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FT-IR). The specific surface area (BET) and point of zero charge (PZC) of the two materials were determined. The palladium ions\u2019 recovery from synthetic aqueous solutions studies aimed to establish the adsorption mechanism. For this desideratum, the kinetic, equilibrium and thermodynamic studies show that MgSiO3-DB30C10 have a higher adsorption capacity (35.68 mg g\u22121) compared to MgSiO3-DB18C6 (21.65 mg g\u22121). Thermodynamic studies highlight that the adsorption of Pd(II) on the two studied materials are spontaneous and endothermic processes. The positive values of the entropy (\u0394S0) suggest that the studied adsorption processes show a higher disorder at the liquid\/solid interface. Desorption studies were also performed, and it was found that the degree of desorption was 98.3%.<\/jats:p>","DOI":"10.3390\/ijms221910718","type":"journal-article","created":{"date-parts":[[2021,10,4]],"date-time":"2021-10-04T09:24:15Z","timestamp":1633339455000},"page":"10718","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A New Perspective on Adsorbent Materials Based Impregnated MgSiO3 with Crown Ethers for Palladium Recovery"],"prefix":"10.3390","volume":"22","author":[{"given":"Mihaela","family":"Ciopec","sequence":"first","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oana","family":"Grad","sequence":"additional","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"},{"name":"Research Institute for Renewable Energy of the Politehnica University Timisoara, Musicescu Street, No. 138, 300774 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7572-3703","authenticated-orcid":false,"given":"Adina","family":"Negrea","sequence":"additional","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5015-9306","authenticated-orcid":false,"given":"Narcis","family":"Duteanu","sequence":"additional","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Petru","family":"Negrea","sequence":"additional","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5570-8418","authenticated-orcid":false,"given":"Cristina","family":"Paul","sequence":"additional","affiliation":[{"name":"Faculty of Industrial Chemistry and Environmental Engineering, Politehnica University Timisoara, Bd. V. Parvan, No. 6, 300223 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5137-8164","authenticated-orcid":false,"given":"Catalin","family":"Ian\u0103\u0219i","sequence":"additional","affiliation":[{"name":"\u201cCoriolan Dr\u0103gulescu\u201d Institute of Chemistry, Romanian Academy, Bv. 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