Green Biosynthesis of Zinc Oxide Nanoparticles for Sustainable Petroleum Applications: A Review
Jian Fu, Jingyi Kou, Yuxiao Han, Zekun Wang, Fan Zhang, Shanshan Sun, Yuehui She
Abstract
Enhanced oil recovery (EOR) technologies are critical for promoting efficient development of petroleum resources, ensuring national energy security, and achieving cleaner production goals. In recent years, green and biocompatible nanomaterials have attracted increasing attention in petroleum engineering due to their environmental compatibility, structural tunability, and interfacial regulation capabilities. This review focuses on recent advances in the green biosynthesis of zinc oxide nanoparticles (ZnO NPs) and their multidimensional applications in enhancing oil recovery. It systematically summarizes and evaluates current biosynthetic strategies based on renewable biological resources, including microorganisms, plant extracts, and algae, and provides an in-depth comparison of how different biosynthetic pathways influence the particle size, morphology, dispersibility, crystallinity, and functional properties of ZnO NPs. The underlying mechanisms of green synthesis are discussed in relation to critical control parameters such as reaction temperature, pH, metal precursor concentration, and reductant characteristics. On this basis, the review comprehensively outlines the mechanisms by which ZnO NPs and their composites with other metals enhance oil recovery, including wettability alteration, interfacial tension reduction, foam and emulsion stabilization, improvement of mobility ratio, catalytic viscosity reduction of heavy oil, and generation of structural disjoining pressure. Recent laboratory investigations and field trials are reviewed to summarize the practical progress of ZnO NPs in drilling fluid performance regulation, fracturing fluid stabilization, corrosion protection in oil and gas transportation systems, and synergistic removal of organic pollutants and heavy metals from produced wastewater. Finally, this review critically analyzes the key challenges facing the industrial application of ZnO NPs, such as scalable green synthesis, long-term stability, environmental risk assessment, and cost-effectiveness. It further highlights future research directions, including structural regulation, multifunctional material integration, reservoir adaptability, and life-cycle sustainability assessment. Overall, this work aims to provide a comprehensive theoretical foundation and technical reference for the deep integration of green ZnO nanomaterials in the petroleum industry, thereby contributing to its green transition and sustainable development.