Optimization of boric acid extraction from ulexite mineral by using supercritical carbon dioxide

İpeksever S., GÖNEN M.

Journal of Supercritical Fluids, vol.166, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 166
  • Publication Date: 2020
  • Doi Number: 10.1016/j.supflu.2020.104998
  • Journal Name: Journal of Supercritical Fluids
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Food Science & Technology Abstracts, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Boric acid, Reactive extraction, Supercritical CO2, Sequestration, Box-Behnken design, DISSOLUTION KINETICS, LEACHING KINETICS, CO2 SEQUESTRATION, COLEMANITE, ORE
  • Süleyman Demirel University Affiliated: Yes


The utilization of carbon dioxide (CO2) in chemical processes is one plausible solution for decreasing greenhouse gases in the atmosphere. Herein, a boric acid extraction process was developed utilizing CO2 as a leaching agent. Three-factor three-level Box-Behnken design model was employed to investigate and optimize process variables of temperature, pressure and reaction time for reactive extraction from ulexite mineral using carbon dioxide. A 91.8 % boric acid extraction yield was obtained at 70 degrees C and 9 MPa with a reaction time of 170 min. At the end of reaction, the heterogeneous mixture was separated by vacuum filtration. The presence of Na (8.72% wt.) in EDX analysis confirmed the crystallized powder has sodium borate. The filter cake was determined as calcium carbonate from the XRD and FTIR analyses. Utilizing supercritical CO2 as a leaching agent is a viable solution to sequester CO2 collected as calcium carbonate while also producing commercially relevant boric acid. (C) 2020 Elsevier B.V. All rights reserved.