Green hydrogen has become a strategic energy vector for global decarbonization, and among the different production pathways, Chemical Looping (CLC, CLH, CLR) stands out for its high efficiency and intrinsic CO₂ capture capacity. This study presents a technological surveillance review of chemical looping processes for hydrogen production, with emphasis on oxygen carrier materials such as alumina (Al₂O₃), under a Life Cycle Assessment (LCA) perspective following ISO 14040/14044 guidelines. The methodology consisted of a systematic literature review covering advances in chemical looping configurations, the role of solid oxygen carriers, and the use of LCA software such as SimaPro, GaBi, OpenLCA, and Aspen Plus to quantify environmental impacts. The results show that chemical looping enables hydrogen generation while inherently separating CO₂, minimizing the need for post-combustion treatments. Alumina-based carriers provide high thermal stability, durability, and reactivity support, yet their industrial production through the Bayer process is energy-intensive and associated with significant environmental burdens, including greenhouse gas emissions and the generation of red mud waste. LCA studies reveal that the choice of oxygen carrier significantly affects global warming potential, fossil resource depletion, and other environmental indicators, highlighting the need to optimize material performance and integrate renewable energy sources. In conclusion, chemical looping technologies represent a promising pathway for sustainable hydrogen production, provided that challenges related to economic scalability, environmental performance of oxygen carriers, and waste management are addressed. Incorporating LCA into process design is essential to ensure that the deployment of chemical looping effectively contributes to the transition towards cleaner energy systems.