Water permeability and chloride-ion penetration resistance of eco-friendly concrete from ground palm oil fuel ash

High energy consumption in cement production leads to emissions of greenhouse gases, such as carbon dioxide. In this study, palm oil fuel ash (POFA) was utilised as partial cement replacement at 0%, 15%, 25%, and 35% to evaluate compressive strength, water permeability and chloride resistance of concrete up to 90 days. Rapid chloride-ion penetration and chloride diffusion were assessed using standard chloride permeability tests. The compressive strength of POFA concretes ranged from 90–98% of control concrete at 28 days. At 25% POFA, water permeability was lower than that of control concrete, despite slightly lower strength. Chloride resistance improved with higher POFA levels, with 35% POFA reducing charge passed by 73% at 28 days. Empirical models based on power law regression were developed using POFA content, compressive strength and curing age. The models showed high predictive accuracy, particularly for chloride resistance (R2 = 0.98), and revealed key links between transport properties and mixture factors. Ground POFA up to 35% is suitable for marine applications with high chloride exposure. The use of ground POFA as a supplementary cementitious material supports sustainable concrete production by reducing cement consumption and enhancing long-term durability, contributing to UN SDGs 9, 12 and 13.