Wu Jianhui, Xu Tong, Chu Hongqiang, Xi Xiang, Zhang Fengchen, Jin Weizhun
College of Mechanics and Materials, Hohai University, Nanjing 211100, China.
Materials (Basel). 2023 Oct 19;16(20):6766. doi: 10.3390/ma16206766.
To address the issues of low strength, poor water stability, and hazardous substance leaching associated with using phosphogypsum (PG) as a direct road-based material, the traditional approach involves employing inorganic cementing materials to stabilize PG, effectively addressing the problems. This study innovatively utilizes the xanthan gum (XG) and sodium methylsiliconate (SM) as curing agents for PG to solve the above problems. An organic curing agent stabilized PG was prepared by dry mixing XG and PG. The unconfined compressive strength, water stability, and leaching behavior of stabilized PG were investigated, the leaching behavior was characterized by ion leaching concentration, and the mechanisms behind the strength development of stabilized PG were explored by SEM and FTIR. The experimental results indicate that the single incorporation of XG reduced the strength and water stability of stabilized PG, while the single incorporation of SM had a limited effect on strength and water stability. In addition, the dual incorporation of XG and SM significantly improved the strength and water stability of stabilized PG. At the same time, the dual incorporation of XG and SM greatly reduced the leaching of hazardous substances from stabilized PG. These results demonstrate the feasibility of using stabilized PG for road base materials.
为解决将磷石膏（PG）用作直接道路基层材料时强度低、水稳定性差和有害物质浸出等问题，传统方法是采用无机胶凝材料来稳定磷石膏，从而有效解决这些问题。本研究创新性地使用黄原胶（XG）和甲基硅酸钠（SM）作为磷石膏的固化剂来解决上述问题。通过将XG与PG干混制备了有机固化剂稳定的PG。研究了稳定化PG的无侧限抗压强度、水稳定性和浸出行为，通过离子浸出浓度表征浸出行为，并通过扫描电子显微镜（SEM）和傅里叶变换红外光谱（FTIR）探究稳定化PG强度发展的机理。实验结果表明，单独掺入XG会降低稳定化PG的强度和水稳定性，而单独掺入SM对强度和水稳定性的影响有限。此外，XG和SM的双重掺入显著提高了稳定化PG的强度和水稳定性。同时，XG和SM的双重掺入大大减少了稳定化PG中有害物质的浸出。这些结果证明了使用稳定化PG作为道路基层材料的可行性。
