Comparative evaluation of carbon capture separation technologies for shipboard applications using multi-criteria decision analysis

Maritime transportation accounts for approximately 3.1% of global anthropogenic CO₂ emissions while enabling nearly 85% of world trade, prompting increasingly stringent regulations to decarbonize the sector. Ship-based carbon capture systems (CCS) have emerged as a promising transitional solution to support regulatory compliance and emission reduction. This study evaluates alternative carbon capture methods and technologies for maritime applications using a multi-criteria decision-making framework. Six evaluation criteria, maturity, efficiency, energy demand, cost, applicability, and safety, were identified based on the literature. Criterion weights were derived using the Analytic Hierarchy Process (AHP) with expert input and complemented by objective entropy weighting. A hybrid AHP–entropy approach was employed to balance subjective judgment with data-driven insights, while sensitivity and bounded perturbation analyses were conducted to assess robustness. The results indicate that post-combustion carbon capture is the most suitable method for shipboard application. Among the evaluated technologies, chemical adsorption ranks highest, followed by chemical looping combustion and membrane separation. The rankings remain stable under reasonable uncertainty in both weighting and performance scoring. Overall, the proposed framework provides a transparent and robust decision-support tool for monitoring CCS configurations in maritime transport.