Direct ammonium sulfate production from untreated industrial phosphogypsum under mild conditions: process evaluation
Journal of Chemical Technology and Biotechnology, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1002/jctb.70247
- Dergi Adı: Journal of Chemical Technology and Biotechnology
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, BIOSIS, Chemical Abstracts Core, Chimica, Compendex, EMBASE, INSPEC, Natural Science Collection (ProQuest), Biological Science Database (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO), Engineering Source (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Anahtar Kelimeler: ammonium sulfate synthesis, mineral carbonation, phosphogypsum valorization, process evaluation
- Ankara Üniversitesi Adresli: Evet
Özet
BACKGROUND: Industrial phosphogypsum valorization typically requires energy-intensive pretreatments. This study provides a baseline approach by evaluating direct, single-step conversion of raw, untreated phosphogypsum into ammonium sulfate and calcium carbonate under mild laboratory conditions (55 °C, 3 h, atmospheric pressure, 1:4 solid-to-liquid ratio) using 12–14 wt% NH4OH solutions. RESULTS: Untreated phosphogypsum demonstrated sufficient intrinsic reactivity to produce crystalline (NH4)2SO4 with a high purity of 96–98.29%, containing 20.31–20.54 wt% nitrogen and 23.03–23.54 wt% sulfur. The highest reaction efficiency and product purity were achieved using a 13 wt% NH4OH solution. Due to heterogeneous reaction constraints and mass transfer resistance, the overall conversion efficiency remained moderate at 23.13–29.31%, yielding 1.53–1.93 g of product against a theoretical yield of 6.61 g. CONCLUSION: The consistent formation of high-purity (NH4)2SO4 directly from raw, inactivated phosphogypsum validates the technical viability of this simplified waste-to-resource framework. While surface-related and thermodynamic limitations present clear efficiency boundaries that require future process optimization, the elimination of energy-intensive pretreatments represents a significant step toward cost-effective industrial sustainability. This study lays a solid foundation for upcoming pilot-scale validations, comprehensive mass–energy balances, and integrated CO2 sequestration strategies. © 2026 Society of Chemical Industry (SCI).