Palm oil clinker (POC), a by-product from palm oil industry, has gained attention as a potential sand replacement in concrete. This study focuses on the grading of palm oil clinker sand (POCS) as a whole replacement of conventional sand in cement and geopolymer mortars. Fly ash (FA) and ground-granulated blast-furnace slag (GGBS) were used as binders and activated with a Na₂SiO₃/NaOH ratio of 1.5 in geopolymer mixes. Four different gradings of POCS with a maximum size of 4.75, 2.36, 1.18, and 0.60 mm, along with a control mix with the utilization of Mining sand (MS), were used to cast a total of 10 mixes for cement and geopolymer mortars. The microstructure of the POCS was analysed, and engineering properties of mortars were investigated through flow table test, compressive and flexural strengths, density, drying shrinkage, water absorption and sorptivity tests, and SEM images. The results revealed that mixes with the incorporation of finer POCS particles produced better compressive, flexural, and water absorption values, while the opposite was experienced in terms of drying shrinkage. Overall, the density of the mixes incorporating POCS was reduced by up to 20% and POCS geopolymer mortars produced higher strengths than those of cement. A 28-day compressive strength of 55–65 MPa was produced with the utilization of POCS in geopolymer mortar under the ambient temperature of 26–28 °C.

棕榈油熟料 (POC) 是棕榈油工业的一种副产品，作为混凝土中潜在的沙子替代品而受到关注。本研究的重点是棕榈油熟料砂 (POCS) 的分级，作为水泥和地质聚合物砂浆中常规砂的整体替代品。粉煤灰 (FA) 和磨碎的高炉矿渣 (GGBS) 用作粘合剂并用 Na ₂ SiO ₃活化地质聚合物混合物中的 /NaOH 比为 1.5。四种不同等级的最大尺寸为 4.75、2.36、1.18 和 0.60 毫米的 POCS 以及使用矿砂 (MS) 的对照混合物被用于浇注总共 10 种用于水泥和地质聚合物砂浆的混合物。分析了 POCS 的微观结构，并通过流动表试验、抗压和抗弯强度、密度、干缩、吸水和吸水率试验以及 SEM 图像研究了砂浆的工程性能。结果表明，掺入更细的 POCS 颗粒的混合物产生了更好的压缩、弯曲和吸水值，而在干燥收缩方面则相反。总体，加入 POCS 的混合物的密度降低了 20%，POCS 地质聚合物砂浆的强度高于水泥。在 26-28 °C 的环境温度下，在地质聚合物砂浆中使用 POCS 产生了 55-65 MPa 的 28 天抗压强度。