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The heterogeneous oxidation of olefins to vicinal diols was investigated using an Os-Zn-Al hydrotalcite-like catalyst (HTlc). The Os-Zn-Al HTlc was synthesised by the co-precipitation method and characterised fully using XRD, FT-IR, TEM, SEM, ICP-OES and BET surface area measurements. The ability of the synthesised Os-Zn-Al HTlc to catalytically dihydroxylate olefins to vicinal diols using various co-oxidants (air, NMO, K3Fe(CN)6, H2O2 and t-BuOOH) was investigated. The focus was mostly on N-methylmorpholine N-oxide (NMO) and K3Fe(CN)6 since they are well established co-oxidants for osmium catalysed dihydroxylation. When NMO was used, 100 % olefin conversion was achieved for all olefins tested. While, 100% conversion was only achieved with electron rich olefins when K3Fe(CN)6 was used as co-oxidant. Recyclability and leaching tests were done, and it was found that the catalyst could be recycled at least 3 times in the NMO system and the K3Fe(CN)6-K2CO3 system was found to be truly heterogeneous.

In the face of mounting water supply challenges, Cape Town has increasingly turned to alternative sources, like groundwater. However, the utilisation of groundwater carries inherent risks, particularly the contamination stemming from land-based activities, such as fuel stations. Leaks from underground tanks at these stations represent a major global cause of groundwater pollution, and Cape Town is no exception. To safeguard public health and mitigate potential harm, it is imperative to examine the legal regulations governing fuel station development, assess measures for controlling their environmental impacts and evaluate strategies for managing the associated risks. This study aims to provide an exhaustive review of the regulatory framework concerning the environmental impacts of fuel stations, focusing on groundwater protection in Cape Town. A combination of desk research and interviews was employed to gather and analyse data. The findings show a deficiency in precautionary measures for safeguarding groundwater near fuel stations. Consequently, through this study, the existing legal framework's effectiveness is called into question, with this study suggesting actions to address these identified shortcomings. [ABSTRACT FROM AUTHOR]

The neutron activation of stable isotopes in environmental matrices, such as soil and groundwater, is a critical aspect of assessing the impact of radionuclide production facilities on the surrounding ecosystem. The envisioned Low-Energy Radioactive Ion Beams (LERIB) facility at the iThemba LABS, South Africa is anticipated to generate significant sources of ionising radiation. The study investigated the possible repercussions of neutron irradiation stemming from the facility, focusing on the activation of stable isotopic compositions in the environment. The investigation employed a combination of experimental and analytical techniques to characterize the neutron activation products in soil and groundwater samples collected from the vicinity. Samples were collected from designated areas for background radiological measurements and were irradiated with neutrons for a period of 1 h. The induced radioactivity measured by the High Purity Germanium detector included 24 Na, 22 Na, 54 Mn, 52 Mn, and 46 Sc. The application of Darcy's law for groundwater velocity suggests that radionuclides in groundwater will migrate at an average flow velocity of 0.8 m/day. The isotopes with longer half-lives have count rates at background concentrations; therefore, environmental impacts on the site and surrounding communities might be minimal., Competing Interests: The authors declare there is no conflict., (© 2024 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).)