Felaous Khadija, Aziz Ayoub, Achab Mohammed
Geo-Biodiversity and Natural Patrimony Laboratory (GEOBIO), Scientific Institute, "Geophysics, Natural Patrimony and Green Chemistry" Research Center (GEOPAC), Mohammed V University in Rabat, Avenue Ibn Batouta, P.B. 703, 10106, Rabat-Agdal, Morocco.
Environ Sci Pollut Res Int. 2023 Jan;30(2):3549-3561. doi: 10.1007/s11356-022-22461-7. Epub 2022 Aug 10.
Natural diatomite, an amorphous siliceous rock, was used as a source of silica for the synthesis of a silicate gel to replace commercial sodium silicate gel in the synthesis of geopolymers from blast furnace slag at room temperature. Nine diatomite gels were synthesized by varying the diatomite content in the gel by 0, 10, and 15% and the NaOH molarity by 6 M, 8 M, and 10 M. The chemico-mineralogical and microstructural characterization results of the elaborated geopolymers showed that the blast furnace slag activation by diatomite gel under optimal conditions (8 M NaOH molarity and 10% diatomite) leads to a good dissolution and polycondensation of the precursor by forming amorphous gels of C-A-S-H type, as well as the mineral phase hydrotalcite, which are the same geopolymerization products detected in the case of the use of conventional silicate gel, and consequently, the obtaining of a geopolymer with interesting physical-mechanical characteristics: compressive strength of 42 MPa, density of 1. 61 g/cm, ultrasonic pulse velocity of 3855 m/s. Thus, this new approach used in this work proved to be successful in reducing the cost and environmental impact of geopolymers.
天然硅藻土是一种无定形硅质岩，被用作二氧化硅的来源，用于合成硅酸盐凝胶，以在室温下从高炉矿渣合成地质聚合物时替代商业硅酸钠凝胶。通过将凝胶中的硅藻土含量分别设置为0%、10%和15%，以及将氢氧化钠摩尔浓度分别设置为6M、8M和10M，合成了九种硅藻土凝胶。对制备的地质聚合物进行的化学矿物学和微观结构表征结果表明，在最佳条件下（8M氢氧化钠摩尔浓度和10%硅藻土），用硅藻土凝胶对高炉矿渣进行活化，会使前驱体发生良好的溶解和缩聚，形成C-A-S-H型无定形凝胶以及矿物相水滑石，这些与使用传统硅酸盐凝胶时检测到的地质聚合产物相同，因此，获得了具有令人感兴趣的物理力学特性的地质聚合物：抗压强度为42MPa，密度为1.61g/cm，超声脉冲速度为3855m/s。因此，这项工作中使用的这种新方法在降低地质聚合物的成本和环境影响方面被证明是成功的。
