Circular Economy (CE) aims to achieve sustainability through recycling, refurbishing, reusing, and other similar activities. Even though the concept of CE has gained considerable interest throughout the previous years and yielded significant research contributions, many critics stress the lack of incorporating ethical and social considerations into CE. This thesis researches how to facilitate such embedding of socio-ethical aspects into CE through the support of the Responsible Research and Innovation (RRI) methodology. Thus, this thesis addresses the main research question “How can the RRI methodology complement the CE framework to assess ethical, legal, and social aspects (ELSA)?”. Within this study, a conceptual framework was developed that allows for embedding socio-ethical aspects in terms of assessing ELSA (aspects) that are seen as design points contributing to a socio-ethical responsible and just CE. This framework contains substantial elements of RRI, including its four dimensions (Inclusion, Anticipation, Reflexivity, Responsiveness) suggested by Stilgoe et al. (2013). Furthermore, the conceptual framework is inspired by a draft framework of Purvis et al. (2023) for a responsible CE, claiming their framework as a starting point and suggesting future recommendations for its further refinement. The conceptual framework developed in this thesis allows for an inclusive assessment procedure of (bounded) CE systems by addressing its various components and all involved stakeholders by actively communicating with them. The system’s components, such as of technical or organizational nature, must be thoroughly assessed to recognize potential ELSA risks/impacts that can harm a responsible CE. Defining appropriate design points serve to mitigate such risks.

In order to test and evaluate the conceptualized framework, it got applied to a case study. The Horizon Europe granted project ALICIA represents the case study environment. ALICIA intends to establish a CE for industrial automotive manufacturing equipment (machinery and robots) within Europe. Since circularity for industrial automotive manufacturing equipment constitutes, especially on this scale, an under-researched field, this research also investigates such an automotive CE approach. Through the framework’s demonstration, significant findings could be obtained. First, even though the framework manifested as effective due to the achieved insights, which are subsequently further expressed, future recommendations for further development regarding the framework's recognized limitations are suggested. Another crucial insight the case study provided emphasizes the major challenges that exist in realizing a CE for automotive production equipment. Those challenges were identified by assessing the ELSA risks of ALICIA and the design points to mitigate such. To realize equipment circularity, detailed data must be shared by companies that often contain sensitive corporational information. Originating from the automotive industry’s competitiveness, such data exchange is hard to realize as it can jeopardize companies’ privacy. To overcome this, it requires collaboration between the companies and clearly defined data-sharing policies to enable such data exchange. Such ideal data exchange should ensure that still, sufficient data is shared to realize equipment circularity but simultaneously does not infringe a corporation’s privacy which could harm their market position by disclosing it to competitors.

Additionally, since the automotive industry is a profit-driven one, socio-ethical dimensions must also be incorporated into such equipment CE from the beginning. Compared to the electric mobility transition, which is another sustainability endeavor of the automotive industry, socio-ethical dilemmas that refer to unethical origins of certain parts (e.g., lithium batteries), such as child labor or farm desiccation, are prevalent. To prevent such or similar dilemmas within the sustainability agenda of an automotive CE, it requires the embedding of socio-ethical considerations that were detected throughout the case study. These considerations contain to ensure, inter alia, an ethical origin of parts used for equipment refurbishment. Otherwise, if these socio-ethical issues are neglected from the start, potential drawbacks might be difficult to remedy during an already ongoing CE implementation. These both outlined challenges with their socio-ethical considerations must be more precisely addressed in the future by relevant experts.

Thus, this research's key findings cannot only be seen as beneficial for the methodology of assessing socio-ethical considerations in CE from the context of RRI but also for the circularity of automotive production equipment. Both results constitute fundamental groundwork for further recommended research in these lacking research fields.

When containers are transported on synchromodal bookings from their origin to their destination, the transport supplier can decide which combination of trucks, trains, and ships to use. This gives transport suppliers many options to route the container through the synchromodal network. Current literature on the individual routing of containers assumes that the trucks are always available and they do not consider empty truck kilometers. A model which individually routes both containers and trucks through a synchromodal network is presented in this paper. We study the effect of integrating the route of individual trucks and containers, considering costs, emissions, and empty truck kilometers by creating the Integrated Container and Truck (ICTR) model, and comparing it to the existing assumption in literature that trucks are always available when routing the container through a synchromodal network. Numerical experiments on a simulated, synchromodal, hinterland network are used to illustrate the model's potential.