How do theories serve as foundational pillars in chemical engineering? Discuss the indispensable role of theoretical frameworks in elucidating complex phenomena, optimizing processes, and innovating technologies within chemical engineering. Analyze the significance of theories in providing a fundamental understanding of chemical reactions, thermodynamics, fluid mechanics, and transport phenomena. Explore how theoretical models facilitate the design and operation of chemical processes, enabling engineers to predict system behavior, troubleshoot issues, and enhance efficiency. Consider the interdisciplinary nature of chemical engineering and how theories from chemistry, physics, mathematics, and other fields converge to form a cohesive understanding of chemical processes. Investigate the evolution of theoretical frameworks over time and their adaptation to address contemporary challenges, such as sustainability, renewable energy, and advanced materials. Evaluate the limitations of existing theories and the ongoing quest for novel theoretical approaches to tackle emerging complexities in chemical engineering.