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The accelerated weathering of limestone (AWL) process is an inexpensive and eco-friendly carbon dioxide (CO 2) capture process with comparable performance to amine-based systems. However, the generated calcium bicarbonate (Ca(HCO 3) 2) solution lacks an effective utilization alternative. Aside from that, the current solid waste utilization alternatives (i.e., carbon mineralization and partial replacement of conventional binders) lack the capability to effectively curb the tremendous production rate of solid waste (i.e., cement kiln dust (CKD)). To address both gaps, this study developed a novel Ca(HCO 3) 2 solution utilization alternative with CKD as the sole binder to produce a building material termed CKD-bicarbonate lime mortar (BLM). This work aims to identify the optimal mix ratio for CKD-BLM to achieve maximum compressive strength via a series of studies; (i) liquid medium, (ii) Ca(HCO 3) 2 solution volume, and (iii) sand:CKD mix ratio. From the findings, it was found that CKD-BLM at the optimal CKD:sand:Ca(HCO 3) 2 mix ratio of 1:0.45:0.29 exhibits the highest compressive strength of 2.09 MPa, surpassing the compressive strength standard of 1.70 MPa set by the ASTM C141 while having acceptable workability of 118 % which is within the standard workability range of 105–155 % set by ASTM C270. However, the CKD-BLM sample exhibits high leaching of Ca, Si, Na and Cl which does not meet the environmental regulation. This was resolved by applying a waterproof coating that effectively curbed the leaching by 28.84–99 %. Overall, this study successfully developed a building material with industrial wastes (i.e., Ca(HCO 3) 2 solution and CKD) that surpasses the performance of conventional lime mortar while utilizing up to 0.22 kg CO 2.kg CKD-BLM_1:0.45:0.29−1. [Display omitted] • Cement kiln dust is used as feedstock for bicarbonate mortar production. • CKD-BLM_1:0.45:0.29 was able to achieve a strength of 2.09 MPa. • Generated CKD-BLM are able to meet ASTM standard requirements. • Able to achieve a CO 2 storage capacity of 0.22 kg CO 2.kg CKD-BLM. • Encapsulation with waterproof coating can curb heavy metals leaching up to 99.17 %. [ABSTRACT FROM AUTHOR]

Significant effects of organoclay and poly(melamine-co-formaldehyde)- methylated (PMFM) impregnation on the mechanical, morphological, and thermal characteristics of raw pulai wood were investigated in this work. The material’s modulus of elasticity (MOE) as well as the maximum compression force (MCF) of the impregnated organoclay/PMFM pulai wood samples were optimized using a designed experiment. The MOE and MCF models had R2 values of 0.9228 and 0.8340, respectively. After the impregnation of organoclay/PMFM pulai wood samples, the MOE and MCF increased considerably, indicating that the pulai wood's mechanical characteristics had improved. The compositional analysis verified the polymerization and dispersion of organoclay and PMFM. Using Fourier transform infrared spectroscopy, reduction in the hydroxyl groups was detected. The impregnated organoclay/PMFM pulai wood samples had successfully filled the pores and cell cavities, as seen by scanning electron microscopy. The thermal stability of the impregnated organoclay/PMFM pulai wood samples was better than that of the raw pulai wood, with a higher glass transition temperature as determined by differential scanning calorimetry. The thermogravimetric study revealed that the impregnated organoclay/PMFM pulai wood samples had higher decomposition temperatures than the raw pulai wood sample. [ABSTRACT FROM AUTHOR]