<p>Sustainability has become a critical strategy for mitigating the adverse impacts of global warming. Within this context, remanufacturing under a circular economy framework contributes to energy and resource conservation while simultaneously promoting economic growth and employment generation. This necessitates the development of efficient decision-support systems that enhance resource utilization, maximize product value, and minimize total system costs. The circular economy provides a viable and innovative approach to addressing industrial challenges by encouraging the prudent use of limited natural resources and reducing environmental degradation. This study develops a profit-maximizing inventory model for non-instantaneously deteriorating items by incorporating preservation technology within a circular economy framework. Circular economy practices, as an emerging mechanism for sustainable development, effectively reduce waste generation and environmental pollution while significantly improving profitability. Demand is modeled as a linear function of the circularity index and the logistics unit profit. An optimization algorithm is employed to determine the optimal order quantity and circularity index that maximize the total average profit. Numerical results demonstrate that the non-instantaneous packaging industry can achieve higher profitability while maintaining an optimal level of circularity. Furthermore, sensitivity analysis and managerial insights are provided to examine the effects of key system parameters on operational and economic performance.</p>