Problem: The demand of beverages in PET bottles is constantly increasing. In this context, environmental, technological and regulatory aspects set a stronger focus on recycling. Generally, the reuse of recycled material from post-consumer PET bottles in bottle-to-bottle applications is seen as least environmentally harmful. However, closed-loop systems are not widely implemented in Europe. Previous research mainly focuses on open-loop recycling systems and generally lacks discussion about the current German and Swedish systems and their challenges. Furthermore, previous studies lack theoretical and practical enhancements for bottle-to-bottle recycling from a managerial perspective. Purpose: The purpose of this study is to compare the PET bottle recycling systems in Germany and Sweden, analyse the main barriers and develop enhancements for closed-loop systems. Method: This qualitative study employs a case study strategy about the two cases of Germany and Sweden. In total, 14 semi-structured interviews are conducted with respondents from different industry sectors within the PET bottle recycling systems. The empirical data is categorised and then analysed by pattern matching with the developed theoretical framework. Conclusion: Due to the theoretical and practical commitment to closed-loop recycling, the Swedish PET bottle recycling system outperforms the Germany system. In Germany, bottle-to-bottle recycling is currently performed on a smaller scale without a unified system. The main barriers for bottle-to-bottle recycling are distinguished into (1) quality and material factors, (2) regulatory and legal factors, (3) economic and market factors and (4) factors influenced by consumers. The enhancements for the systems are (1) quality and material factors, (2) regulatory and legal factors, (3) recollection factors and (4) expanding factors. Lastly, the authors provide further recommendations, which are (1) a recycling content symbol on bottle labels, (2) a council for bottle quality in Germany, (3) a quality seal for the holistic systems, (4) a reduction of transportation in Sweden and (5) an increase of consumer awareness on PET bottle consumption.

Two relatively new EPA policies encourage the inclusion of pollution prevention in regulatory enforcement settlements. The advantages to a firm include reduction or elimination of environmental problems at the source (thus decreasing reliance on end-of-pipe controls), enhanced prospects for future compliance, and a potential for a reduction in the assessed penalty. We discuss the factors that influence both EPA and firms to include pollution prevention in enforcement settlements, characterize the process in a few exemplary cases, and recommend ways to enhance and expand these activities. The research presented focused on case study analysis of 10 recent EPA-negotiated enforcement settlements that included chemical substitutions, process changes, or closed-loop recycling

The process of assembling metal nanoparticles at the interface of two liquids has received a great interest over the past few years due to a wide range of important applications and their unusual properties compared to bulk materials. The work in this thesis presents a low cost, simple and cheap synthesis of metal nanoparticles, core/shell structures and semiconductors followed by assembly of these particles between immiscible liquids. The aim of this thesis is divided to three parts (Summary of the experimental work of this thesis is in Table A1):1) To achieve a closed loop recycling for producing cadmium sulfide as powders and/or nanostructured thin films for solar cells or other optoelectronic devices applications. A series of bis(dialkyldithiocarbamato)cadmium(II) were used for this approach. Bis(dioctyldithiocarbamato)cadmium(II) complexes proved to be the optimal alkyl chain for this process. The approach can be extended to other metal sulfides such as those of Zn, Pb, Cu, or Fe and many transition metals and oxides.2) To explore the phenomena of exchange bias in very small size particles (5 nm) of Ni/NiO (core/shell structure) obtained by solution phase synthesis. Ferromagnetism (FM) due to exchange bias is well established in the case of larger particles with diameters over 10 nm. However, sub 10 nm magnetic structures synthesized by solution phase have never been found to be ferromagnetic at room temperature. These Ni/NiO nanocrystals with ferromagnetic properties at room temperature were among the smallest and strongest magnets made in solution. Similar magnets can be obtained using a rare class of high anisotropy materials nearly all of which feature precious metals. This work would lead to significantly cheaper magnetic particles suited for the mass market. The applications of this work can be applied to produce viable storage devices and the other possibility is to disperse these nanocrystals in solution and use it to make ferrofluids which have a number of mature applications. Functional device architectures of these particles were rapidly and inexpensively produced as thin films using self-assembly of liquid/liquid interface process at room temperature by using octylamine as a surfactant.3) To synthesise and assemble submicron particles of silver, cobalt and nickel by using polyol methods and liquid/liquid interface, respectively. The effect of reaction conditions (solvent, precursor concentration, temperature, etc.) on synthesis and assembly of the particles was studied. Assembled cobalt and nickel as films are promising materials for spintronics, magnetic and magneto-electronics and biomedics. The nature and characteristics of the particles and their films were studied by a number of techniques such as SEM, EDX, TEM, p-XRD, UV-Vis, PL, FTIR, DLS and SQUID for magnetic measurements.

Resource scarcity and increasing environmental pressure have raised the stakes for rethinking material efficiency and textile recycling potential. As current practices fail to feed a closed loop recycling system, this research aims to contribute to the improvement of prevailing practices regarding denim as one of the most popular apparel materials worldwide while focusing on the issue of increasing amounts of discarded post-consumer textiles. The superordinate objective to define the optimum point for denim recycling to retain the value of the cotton fibre as long as possible in a closed loop system, thereby elevating the recycling efficiency, can be considered a key driver for the present research. The following data acquisition is constructed and executed along a mixed method research, in which a qualitative approach based on expert interviews informs and builds up on the quantitative counter part of laboratory use simulation testing on two different denim fabrics and vice versa, leading to an embedded research design. A subjective assessment of potential alterations of the denim fabrics’ visual and tactile characteristics, caused by the use simulation, provides quantitative data through an employed expert panel, which is enhanced by objectively recorded results from the conducted tear strength test and comparative weight investigation to inform changes regarding the physical properties. The applied research methods provide parameters to monitor the decomposition and weakening of the overall fabric structure throughout the experiment. The analysis of the data allowed to assign the number of washing and drying cycles, that a denim garment has undergone, to a corresponding degree of degradation. The presented findings are a valuable resource for developing and innovating current open-end recycling options. The maintenance of the raw material value throughout various reprocessing cycles can counteract the elevated natural fibre scarcity. The insights on the material and process level build a fundament for the successful operationalisation and management of sustainable recycling practices. Further research in this field can pave the way towards value retaining circularity.