Hybrid Nanofluids for Carbon Capture

The growing urgency of climate change, driven primarily by anthropogenic carbon dioxide ( https://www.w3.org/1998/Math/MathML" display="inline"> CO 2 https://www.w3.org/1999/xlink" xlink:href=" https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003628071/4cf83c91-4355-4be6-ba21-1579c8f56e0b/content/ieq0128.tif "/> ) emissions, necessitates innovative and sustainable capture technologies beyond conventional solvents. Hybrid nanofluids are engineered suspensions of nanoparticles in base liquids. Nanofluids have emerged as promising alternatives for enhancing https://www.w3.org/1998/Math/MathML" display="inline"> CO 2 https://www.w3.org/1999/xlink" xlink:href=" https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003628071/4cf83c91-4355-4be6-ba21-1579c8f56e0b/content/ieq0129.tif "/> absorption through synergistic improvements in thermal, mass transfer, and interfacial properties. This chapter explores the fundamental role of nanofluids in carbon capture, detailing mechanisms such as enhanced thermal conductivity, increased specific heat, micro-convection-driven mass transfer, and tunable viscosity and surface tension. Both physical and chemical absorption pathways are discussed, highlighting the catalytic roles of nanoparticles in accelerating reaction kinetics, stabilizing solvents, and reducing regeneration energy. The potential of diverse nanoparticle classes consisting of metal oxides, carbon-based nanostructures, and multifunctional hybrids is critically evaluated alongside base fluids such as water, amines, and ionic liquids. Modeling approaches ranging from reaction-diffusion and Sherwood number correlations to emerging machine learning and multiscale simulations provide predictive insights into absorption performance. Despite these advances, challenges persist, particularly in terms of nanofluid stability, agglomeration, scale-up economics, and environmental safety. Strategies for overcoming these barriers, such as surface functionalization, smart nanofluids, predictive maintenance via digital twins, and circular economy approaches, are discussed to pave the way for industrial deployment. By integrating materials science, process engineering, and sustainability frameworks, hybrid nanofluids represent a transformative pathway toward efficient, scalable, and eco-friendly https://www.w3.org/1998/Math/MathML" display="inline"> CO 2 https://www.w3.org/1999/xlink" xlink:href=" https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003628071/4cf83c91-4355-4be6-ba21-1579c8f56e0b/content/ieq0130.tif "/> capture systems, offering vital contributions to global carbon neutrality goals.