文献类型：期刊文献

英文题名：Microstructural evolution and mechanical response mechanism of coal treated with acidified SiO2 nanofluid

作者：Liu, Xianfeng He, Chengyi Nie, Baisheng Zhao, Xun Li, Jialiang Qi, Linfan Jia, Xueqi Han, Han

第一作者：Liu, Xianfeng

通信作者：Nie, BS[1]

机构：[1]Chongqing Univ, Sch Resources & Safety Engn, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing 400044, Peoples R China;[2]Guizhou Inst Technol, Inst Min Engn, Guiyang 550025, Peoples R China;[3]Guizhou Mine Safety Sci Res Inst Co Ltd, Guiyang 550025, Peoples R China

第一机构：Chongqing Univ, Sch Resources & Safety Engn, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing 400044, Peoples R China

通信机构：corresponding author), Chongqing Univ, Sch Resources & Safety Engn, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing 400044, Peoples R China.

年份：2026

卷号：408

外文期刊名：FUEL

收录：;EI(收录号：20254919636011);Scopus(收录号：2-s2.0-105023418364);WOS:【SCI-EXPANDED(收录号:WOS:001631056200001)】；

基金：This work is financially supported by the National Key Research and Development Program of China (2024YFC3013804) , and the National Natural Science Foundation of China (52274173) .

语种：英文

外文关键词：Coal; SiO 2 nanoparticles; Mechanical property; Structure evolution

摘要：To address the challenges of dynamic disasters in deep coal mining caused by high stress and low permeability, this study proposes a novel coal modification technique using acidified SiO2 nanofluid. Nuclear magnetic resonance (NMR) and computed tomography (CT) were employed to quantitatively characterize the evolution of pore-fracture structures in coal samples treated with acidified SiO2 nanofluids at a fixed concentration of 2 wt% and pH values ranging from 2 to 7. Uniaxial compression tests, Brazilian splitting tests, and scanning electron microscopy (SEM) were further conducted to elucidate the mechanical response mechanisms of coal under nanofluid treatment. The results demonstrate that acidified SiO2 nanofluid significantly enhances the pore-fracture structure and modulates the mechanical properties of coal. At pH 4 and pH 2, the modified coal samples exhibited porosities of 5.8468 % and 5.889 %, with CT-derived fracture porosity reaching 24.81 % and 18.63 %, respectively-more than double that of water-soaked samples-indicating a substantial improvement in permeability. Mechanically, samples treated with neutral nanofluid achieved a uniaxial compressive strength of 13.76 MPa and a Brazilian tensile strength of 2.35 MPa, representing increases of 47.05 % and 9.26 %, respectively. However, higher acidity levels gradually reduced the mechanical strength and promoted a transition in fracture morphology from transgranular to intergranular patterns. Notably, at pH 4, the acidified SiO2 nanofluid optimized both structural and mechanical properties simultaneously. The study reveals a competitive mechanism between acid-induced pore propagation and nanoparticle-infilled sealing under the synergistic action of SiO2 nanoparticles and acidic fluid, offering new theoretical and technical pathways for the optimization of deep coal seam structures and enhanced mining safety.