Zain-Ul-Abdein Muhammad, Ahmed Furqan, Channa Iftikhar Ahmed, Makhdoom Muhammad Atif, Ali Raza, Ehsan Muhammad, Aamir Abdullah, Ul Haq Ehsan, Nadeem Muhammad, Shafi Hafiz Zahid, Shar Muhammad Ali, Alhazaa Abdulaziz
Department of Metallurgical and Materials Engineering (MME), Faculty of Chemical, Metallurgical and Polymer Engineering, University of Engineering and Technology (UET), Lahore 54890, Pakistan.
Department of Metallurgical Engineering, NED University of Engineering and Technology, Off University Road, Karachi 75270, Pakistan.
Materials (Basel). 2022 Nov 3;15(21):7757. doi: 10.3390/ma15217757.
Natural soil (NS)-based geopolymers (GPs) have shown promise as environmentally friendly construction materials. The production of ordinary Portland cement is known to release significant amounts of greenhouse gas (CO) into the atmosphere. The main objective of this work is to synthesize a geopolymer (GP) from an uncommon aluminosilicate-based NS and a sodium silicate (SS) activating solution that would not only minimize the emission of harmful gases, but also offer improved mechanical strength. Samples of different compositions were produced by varying the wt.% of NS from 50% to 80% and adding a balancing amount of SS solution. The drying and curing of the samples were carried out in an electric oven at specific temperatures. The degree of geopolymerization in the samples was measured by Fourier transform infrared spectroscopy, and microstructural analysis was performed using a scanning electron microscope. Mechanical tests were conducted to evaluate the range of compressive strength values of the prepared GP samples. A minimum compressive strength of 10.93 MPa at a maximum porosity of 37.56% was observed in a sample with an NS to SS ratio of 1:1; while a ratio of 3:1 led to the maximum compressive strength of 26.39 MPa and the minimum porosity of 24.60%. The maximum strength (26.39 MPa) was found to be more than the reported strength values for similar systems. Moreover, an improvement in strength by a factor of three has been observed relative to previously developed NS-based GPs. It may be inferred from the findings that for the given NS, with almost 90% aluminosilicate content, the extent of geopolymerization increases significantly with its increasing proportions, yielding better mechanical strength.
基于天然土壤（NS）的地质聚合物（GP）已显示出作为环境友好型建筑材料的潜力。众所周知，普通硅酸盐水泥的生产会向大气中释放大量温室气体（CO）。这项工作的主要目标是由一种不常见的铝硅酸盐基天然土壤和硅酸钠（SS）活化溶液合成一种地质聚合物（GP），这不仅能将有害气体的排放降至最低，还能提供更高的机械强度。通过将天然土壤的重量百分比从50%变化到80%并添加等量的硅酸钠溶液，制备了不同成分的样品。样品在特定温度的电炉中进行干燥和养护。通过傅里叶变换红外光谱法测量样品中的地质聚合程度，并使用扫描电子显微镜进行微观结构分析。进行力学测试以评估制备的地质聚合物样品的抗压强度值范围。在天然土壤与硅酸钠比例为1:1的样品中，观察到最大孔隙率为37.56%时的最小抗压强度为10.93MPa；而比例为3:1时导致最大抗压强度为26.39MPa和最小孔隙率为24.60%。发现最大强度（26.39MPa）超过了类似体系报道的强度值。此外，相对于先前开发的基于天然土壤的地质聚合物，强度提高了三倍。从这些发现可以推断，对于给定的天然土壤，其铝硅酸盐含量近90%，地质聚合程度随着其比例的增加而显著增加，从而产生更好的机械强度。
