With the increasing importance of research into biomass as a feedstock for the chemical industry, new methods to reduce the oxygen content of biomass are required. Here, we present our progress in the field of the dehydration reaction, using various rhenium-based catalysts, with rhenium(VII) oxide as the most active catalyst. A wide range of allylic, aliphatic, and homoallylic alcohols have been used as substrates under relatively mild conditions (100−150°C, 0.5 mol % catalyst loading, technical toluene, ambient atmosphere) as well as various biobased terpene alcohols. Furthermore, we have applied our protocol to tea tree oil as a proof of concept for the catalytic upgrading of essential oils. The reactivity and selectivity of rhenium(VII) oxide is compared with a classical acid catalyst; sulfuric acid; and solid acid catalysts, such as acid resins, zeolites, and mesoporous materials. It was found that rhenium(VII) oxide surpasses all these catalysts in both activity and selectivity and also shows enduring activity after seven recycling runs.

Mononuclear iron(II) complexes with facially coordinating N,N,O-ligands were synthesized as accurate structural mimics of the 2-His-1-carboxylate facial triad found in mononuclear non-heme iron enzymes. Mimicking of the facial triad is achieved by designing sterically demanding ligands providing two histidine-like benzimidazole moieties and a coordinating carboxylate or ester moiety.

Sustainability has become a prominent theme in society and can be considered as an integral part of scientific citizenship. This study investigates to what extent the production, use and re-use of (bio)plastics initiates students’ reasoning and to identify the kind of content knowledge students put forward. The structure of students’ arguments was mapped according to Toulmin's model of argumentation, i.e., claim, data, warrant & backing and qualifier & rebuttals. Students (N = 27, grade 10 & 11) participated in groups of three. The students were introduced to the topic of the production, use and re-use of plastics by watching a video, answering questions, reading articles and having interviews and group discussions. Students were prompted to argue on the sustainability of bioplastics and fossil-based plastics. The results show that students frequently used arguments related to preventing pollution, designing to recycle and designing to degrade. However, themes such as avoiding waste, origin of energy and materials, energy efficiency and costs were rarely used or even absent in students’ reasoning. Overall, the students’ reasoning contained all of Toulmin's categories, and especially the increase in the number of qualifier & rebuttals is interpreted as an indication of awareness of the complexity of the issue at hand. This study underlines that students are able to bring in relevant scientific knowledge when confronted with a suitable sustainability issue, but also more societally oriented arguments enriched their perspective. Implications for the design of interventions aiming to engage students in life cycle analysis (on plastics) are discussed.

This article reports about a lesson series that focuses on engaging students in sustainability, plastics, and life cycle assessment (LCA). The purpose of the lesson series is to give students insights into sustainability in the context of plastics and to foster awareness of and insights into the benefits of the LCA method. The lesson series introduces students to sustainability by enabling them to watch a video, answer questions, read articles, conduct laboratory experiments, and experience the four stages of LCA. In general, the findings reveal that the lesson series evoked in students a more critical view of the life cycle of plastics. The students showed increasing awareness of the complexity of the sustainability issue at hand. In addition, students used their acquired knowledge about LCA and mentioned impact categories in their argumentation. The lesson series evoked predominantly life cycle thinking, and the qualitative part of an LCA, and might thus serve as a stepping stone toward the quantitative assessment. The preliminary results show that the lesson series is effective for evoking life cycle thinking among students and serves as a stepping stone towards life cycle assessment. Future research could focus on setting the goal and scope of the process to be assessed, with emphasis on the functional unit in the context of plastics, and providing students a complete and coherent understanding of the entire cycle of production, use and recycling of plastics.

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Invited for the cover of this issue is the group of Bert Klein Gebbink at Utrecht University, The Netherlands. The cover image shows the structures of the enzyme deacetoxycephalosporin C synthase (DAOCS) and its synthetic analogue.