A valuable approach for sustainable phosphogypsum management: optimisation and economic analysis of K2SO4 fertiliser production

Çelik E., ERTUNÇ S.

International Journal of Environmental Studies, cilt.82, sa.4, ss.1670-1686, 2025 (Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 82 Sayı: 4
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1080/00207233.2025.2507447
  • Dergi Adı: International Journal of Environmental Studies
  • Derginin Tarandığı İndeksler: Scopus, Academic Search Premier, PASCAL, ABI/INFORM, Aerospace Database, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, Communication Abstracts, Compendex, Environment Index, Greenfile, Metadex, Pollution Abstracts, Public Affairs Index, Veterinary Science Database, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.1670-1686
  • Anahtar Kelimeler: fertiliser, Phosphogypsum, potassium sulphate, wet conversion
  • Ankara Üniversitesi Adresli: Evet

Özet

Phosphogypsum (PG), a by-product in the phosphate fertiliser industry, can pose significant environmental and health risks. Converting PG into valuable products provides both ecological and economic benefits. This study investigates the production of potassium sulphate (K2SO4), a widely used fertiliser through the reaction of PG with potassium hydroxide (KOH) in an aqueous sulphuric acid (H2SO4) solution. Different concentrations of H2SO4 were tested to optimise the sulphur content in the final product. Characterisation techniques, including XRF, XRD, FTIR and SEM-EDX confirmed the successful formation of K2SO4. The optimal conditions were found to be a stoichiometric PG/KOH ratio in 100 mL of aqueous solution containing 1.5 vol.% H2SO4 with a reaction time of 90 min under a stirring speed of 170 rpm at 25 °C. The resulting K2SO4 contained 40.36% potassium and 17.96% sulphur with 97.9% purity and an 83% yield. This method offers an effective and sustainable approach to the valorisation of PG waste.