School of Chemistry and Chemical Engineering, Yangtze Normal University, Chongqing 408100, China.
Key Laboratory of Solid Waste Treatment and Resource Recycle (SWUST), Ministry of Education, Southwest University of Science and Technology, 59 Qinglong Road, Mianyang 621010, China.
Ecotoxicol Environ Saf. 2023 Mar 1;252:114582. doi: 10.1016/j.ecoenv.2023.114582. Epub 2023 Feb 1.
Phosphogypsum (PG) contains a lot of soluble phosphate (PO-P) and fluorine ion (F), which seriously has hindered the sustainable development of the phosphorous chemical industry. In this study, a new burning raw material (BRM) as an intermediate product in the cement production process was used for PO-P and F stabilize in PG. The stabilizing mechanism of PO-P and F were investigated by Fourier Transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), Scanning Electron Microscopy (SEM), X-ray fluorescence (XRF) and X-ray spectroscopy system (XPS). The effect of PG and BRM weight ratio, solid-to-liquid ratio, reaction time, and reaction temperature on the concentrations of PO-P and F were studied. The results showed that the concentration of F in the PG leaching solution was 8.65 mg/L and the stabilizing efficiency of PO-P was 99.78%, as well as the pH of the PG leaching solution was 8.12 when the weight ratio of PG and BRM was 100:2, and the solid to liquid ratio was 4:1, reacting for 24 h at the temperature of 30 ℃. PO-P and F were mostly solidified as Ca(PO)F, CaPO(OH), Ca(PO)(OH), CaPO·2HO, CaSOPO(OH)·4HO, CaF, and CaFPO·2HO. Leaching test results indicated that the concentrations of PO-P, F and heavy metals were less than the integrated wastewater discharge standard (GB8978-1996). This study provides a new harmless treatment method for PG.
磷石膏（PG）中含有大量的可溶性磷酸盐（PO-P）和氟离子（F），这严重阻碍了磷化工的可持续发展。本研究采用水泥生产过程中的中间产物新型燃烧原料（BRM）来稳定 PG 中的 PO-P 和 F。采用傅里叶变换红外光谱（FT-IR）、X 射线衍射仪（XRD）、扫描电子显微镜（SEM）、X 射线荧光（XRF）和 X 射线能谱系统（XPS）研究了 PO-P 和 F 的稳定机制。考察了 PG 和 BRM 重量比、固液比、反应时间和反应温度对 PO-P 和 F 浓度的影响。结果表明，PG 浸出液中 F 的浓度为 8.65mg/L，PO-P 的稳定效率为 99.78%，PG 浸出液的 pH 值为 8.12，当 PG 和 BRM 的重量比为 100:2，固液比为 4:1，在 30℃下反应 24h 时。PO-P 和 F 主要以 Ca(PO)F、CaPO(OH)、Ca(PO)(OH)、CaPO·2HO、CaSOPO(OH)·4HO、CaF 和 CaFPO·2HO 的形式固化。浸出试验结果表明，PO-P、F 和重金属的浓度均低于综合污水排放标准（GB8978-1996）。本研究为 PG 提供了一种新的无害处理方法。
