During 2015, the international community agreed three socio-environmental global development frameworks, the: (i) Sustainable Development Goals, (ii) Sendai Framework for Disaster Risk Reduction, and (iii) Paris Agreement on Climate Change. Each corresponds to important interactions between environmental processes and society. Here we synthesize the role of geoscientists in the delivery of each framework, and explore the meaning of and justification for increased geoscience engagement (active participation). We first demonstrate that geoscience is fundamental to successfully achieving the objectives of each framework. We characterize four types of geoscience engagement (framework design, promotion, implementation, and monitoring and evaluation), with examples within the scope of the geoscience community. In the context of this characterization, we discuss: (i) our ethical responsibility to engage with these frameworks, noting the emphasis on societal cooperation within the Cape Town Statement on Geoethics; and (ii) the need for increased and higher quality engagement, including an improved understanding of the science-policy-practice interface. Facilitating increased engagement is necessary if we are to maximize geoscience's positive impact on global development.

Synthesizing and testing bicomposite adsorbents for the removal of environmentally problematic oxy-anions is high on the agenda of research-led universities.Here we present a laboratory module successfully developed at Imperial College London that introduces the advanced undergraduate student in engineering (chemical, civil, earth) and science (chemistry, materials, earth science) to several fundamental principles associated with this research area in a simple, engaging and safe way. This includes (i) the synthesis of inorganic bicomposite sorbents, (ii) the evaluation of the adsorption−removal process, and (iii) the analysis of the sorbate; all underpinned by theory. We devise an experiment using phosphate oxyanions and an iron−titanium oxide bicomposite sorbent, which is simple to synthesize. The adsorption of phosphate solutions of varying concentration is tested and assessed at pH 5 and 9. Phosphate concentrations at equilibrium are analyzed using UV−vis spectroscopy to plot adsorption isotherms and compare the Langmuir and Freundlich models. This topical introduction to environmental engineering is an excellent opportunity to investigate adsorption processes. The complexity of data interpretation can be tailored to a range of abilities, and the topics addressed in the experiment are relevant starting points for further exploration of environmental geochemistry, pollution control, element transport, and adsorption. We present ready-to-use spreadsheets for the students to facilitate data analysis.

The impact of Sb(III) on the removal of As(III) from solution with activated alumina (AA), a widely employed low cost sorbent for various types of water treatments, was assessed. Adsorption isotherms were determined for binary element systems with As/Sb concentration ratios of 5:1, 9:1, and 12:1 to mimic conditions in water treatment facilities. These were compared to those established for single element systems. There was an increase in Sb(III) adsorption in the binary system compared to the Sb(III) only system. Conversely, in binary systems, As(III) adsorption decreased compared to the As(III) only system. These effects were similar at low and high As(III) concentrations (20 and 240 µg/mL, respectively) and at low and high pH (7.2 and 9.2). Adsorption in single element systems was well-modeled using Freundlich theory (R 2 g 0.92). For As: log q e ) 0.521 log C e -0.064; K f ) 1.066, 1/n ) 0.52. For Sb: log q e ) 0.703 log C e -0.258; K f ) 0.552, 1/n ) 0.70. The equation and constants determined for As(III) agree well with previous work, while those determined for Sb(III) are the first published. However, these equations do not fit for the binary systems, suggesting that other processes become important. This may be explained by the higher pH of As-containing solutions, leading to changes in both the speciation of the As and Sb and the surface charge of the AA, and possible competitive behavior between Sb(III) and As(III). We suggest that the concentration of Sb in waters treated for As should be monitored and further research is required to quantify and understand the impact of low concentrations of Sb on the removal of As through adsorption.

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Naturally occurring goethites often show Al for Fe substitution approaching 33 mol% Al. This substitution has potential to influence the rate of goethite dissolution and therefore the supply of bioavailable Fe. Siderophores such as ferrichrome and enterobactin have considerable potential to dissolve Fe from Fe 3? rich minerals, including Al-substituted goethites. Here, we show that Al substitution in synthetic goethites (0.021 C x C 0.098) gives rise to a significant increase in both ferrichrome-and enterobactin-mediated dissolution rates. In the presence of ferrichrome, Al-goethite (x = 0.033) yields a dissolution rate of 19.0 9 10 -3 lmol m -2 h -1 , nearly twice that of pure goethite, whereas dissolution of the most highly substituted Al-goethite (x = 0.098) is 36.9 9 10 -3 lmol m -2 h -1, more than threefold greater than the pure mineral. Similarly, in the presence of enterobactin, the dissolution rate of Al-goethite increases with increasing Al substitution. Ferrichrome is a less effective ligand than enterobactin in its dissolution of both pure goethite and the range of Al-goethites, an observation we ascribe to the lower affinity of the hydroxamate functional groups of ferrichrome for both Fe 3? and Al 3? . Despite greater affinity of both ferrichrome and enterobactin for Fe 3? over Al 3? , we observe a broadly congruent dissolution of all our Al-goethites.

New methods of analysis for water quality monitoring to detect inorganic substances are required to meet the demands of determining concentration, particularly at low detection limits, analysing speciation and even identifying the pollution source. Such information is essential to inform public health decisions and to comply with more stringent legislation. This paper concentrates on two case studies, reviewing the development in monitoring methods, and predicting future trends. Arsenic and nitrates detection was selected as these pollutants are particularly problematic from a human health perspective. Additionally, the challenges faced in developing monitoring methods for these chemicals are relevant to a wide range of other inorganics. The current state of the art in detection approaches for these chemicals are discussed along with recommendations for future research to further improve the methods.

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