This study examines key technologies in the circular economy through patent mining and expert evaluations. We identified eleven distinct technology clusters, including Smart Fluid Management Systems, Circular Chemical Processing, and Structural Design for Circularity. Using the S-curve model, we analyzed the maturity stages of these technologies, revealing a mix of mature and emerging technologies. For example, Energy Storage and Electrical Systems have reached maturity, while Circular Chemical Processing and Waste Treatment are still in the growth phase. These findings highlight the varying levels of technological development and the potential for targeted research and investment. To assess sustainability, we used the TOPSIS method, which ranks technologies based on their alignment with the Sustainable Development Goals (SDGs). Our results indicate that Circular Chemical Processing, Thermal Management, and Structural Design for Circularity are key areas for innovation, offering significant potential to contribute to global sustainability goals. The study emphasizes the need for integrated solutions, suggesting that technological progress will be driven by synergies between different technology clusters. It calls for cross-sector collaboration to maximize the impact of these technologies. By combining insights on technological maturity and sustainability alignment, this research provides a strategic roadmap for advancing circular economy practices. It offers guidance for industry stakeholders and policymakers on prioritizing investments in technologies that support long-term sustainability and resource efficiency. In conclusion, this study provides a comprehensive framework for understanding and advancing circular economy technologies, offering valuable insights for accelerating the transition toward a sustainable, circular economy.