{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,8]],"date-time":"2026-03-08T22:26:13Z","timestamp":1773008773887,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,15]],"date-time":"2020-11-15T00:00:00Z","timestamp":1605398400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Center, Poland","award":["OPUS 17 grant 2019\/33\/B\/ST8\/02044."],"award-info":[{"award-number":["OPUS 17 grant 2019\/33\/B\/ST8\/02044."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In this work, low-pressure synthesis of carbon spheres from resorcinol and formaldehyde using an autoclave is presented. The influence of reaction time and process temperature as well as the effect of potassium oxalate, an activator, on the morphology and CO2 adsorption properties was studied. The properties of materials produced at pressureless (atmospheric) conditions were compared with those synthesized under higher pressures. The results of this work show that enhanced pressure treatment is not necessary to produce high-quality carbon spheres, and the morphology and porosity of the spheres produced without an activation step at pressureless conditions are not significantly different from those obtained at higher pressures. In addition, CO2 uptake was not affected by elevated pressure synthesis. It was also demonstrated that addition of the activator (potassium oxalate) had much more effect on key properties than the applied pressure treatment. The use of potassium oxalate as an activator caused non-uniform size distribution of spherical particles. Simultaneously higher values of surface area and total pore volumes were reached. A pressure treatment of the carbon materials in the autoclave significantly enhanced the CO2 uptake at 25 \u00b0C, but had no effect on it at 0 \u00b0C.<\/jats:p>","DOI":"10.3390\/molecules25225328","type":"journal-article","created":{"date-parts":[[2020,11,16]],"date-time":"2020-11-16T22:53:52Z","timestamp":1605567232000},"page":"5328","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Pressureless and Low-Pressure Synthesis of Microporous Carbon Spheres Applied to CO2 Adsorption"],"prefix":"10.3390","volume":"25","author":[{"given":"Iwona","family":"Pe\u0142ech","sequence":"first","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego 10, 70-322 Szczecin, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Sibera","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego 10, 70-322 Szczecin, Poland"},{"name":"Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, al. Piast\u00f3w 50a, 70-311, 70-322 Szczecin, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Piotr","family":"Staciwa","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego 10, 70-322 Szczecin, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2443-1510","authenticated-orcid":false,"given":"Urszula","family":"Narkiewicz","sequence":"additional","affiliation":[{"name":"Department of Chemical and Environment Engineering, Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, Pu\u0142askiego 10, 70-322 Szczecin, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert","family":"Cormia","sequence":"additional","affiliation":[{"name":"Chemistry Faculty, Chemistry Department, Foothill College, 12345 El Monte Road, Los Altos Hills, CA 94022, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,15]]},"reference":[{"key":"ref_1","unstructured":"(2020, September 02). 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