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Organizing undergraduates in chemistry, energy engineering, and chemical engineering specialties to participate in an energy transformation experiment can encourage them to think about the impact of human activities on nature and stimulate them to learn more about the topic. This laboratory experiment demonstrates a general approach to the methanation of syngas in a fixed bed reactor with online chromatographic monitoring. Undergraduates gain the opportunity to operate temperature controllers, mass flowmeters, fixed bed reactors, gas chromatography, and cold traps as well as broaden their knowledge of renewable CO/CO[subscript 2] conversion. The experiment also offers a discussion about the chemical principles in catalytic conversion of syngas to methane, viable alternatives to green fuel sources, and the catalytic reaction process.

Graphitic‐carbon nitride (g‐C3N4), a metal‐free two‐dimensional layered semiconductor material, holds great potential for energy conversion, environmental remediation, and sensing. However, the limited solubility of g‐C3N4 in conventional solvents hinders its widespread application. Improving the dissolution of g‐C3N4 in the liquid phase is highly desired but challenging. Herein, we report an innovative approach to dissolve g‐C3N4 using ZnCl2 molten salt hydrates. The solubility of g‐C3N4 in the solution reaches up to 200 mg mL−1. Density functional theory (DFT) results suggest that ZnCl+H2O is the key species that leads to charge redistribution on g‐C3N4 surface and promotes the dissolution of carbon nitride in the solution. Furthermore, through dilution, the dissolved carbon nitride can be effectively recovered while maintaining its intrinsic chemical structure. The resultant regenerated C3N4 (r‐C3N4) exhibits nanobelt morphology and demonstrates a substantially improved photocatalytic activity in H2O2 production. The rate of H2O2 production over the r‐C3N4 reaches 20,228 μmol g−1 h−1, which is 6.2 times higher than that of pristine g‐C3N4. This green and efficient dissolution route of g‐C3N4 offers an effective approach for its diverse applications. [ABSTRACT FROM AUTHOR]

Conductometric gas sensors made of gas permeable metal oxide ultrathin membranes can combine the functions of a selective filter, preconcentrator, and sensing element and thus can be particularly promising for the active sampling of diluted analytes. Here we report a case study of the electron transport and gas sensing properties of such a membrane made of nanoporous Ta2O5. These membranes demonstrated a noticeable chemical sensitivity toward ammonia, ethanol, and acetone at high temperatures above 400 °C. Different from traditional thin films, such gas permeable, ultrathin gas sensing elements can be made suspended enabling advanced architectures of ultrasensitive analytical systems operating at high temperatures and in harsh environments. [ABSTRACT FROM AUTHOR]

In this paper, photocatalytic production of dihydroxyacetone (DHA) from glycerol in acetonitrile on TiO 2 was investigated. HPLC-MS analysis showed that glycerol was converted to DHA, glyceraldehyde (GAD), glyceric acid and several other chemicals. Using acetonitrile as the reaction medium instead of water not only provided a more selective process for production of DHA but also increased the glycerol conversion. After 300 min, with 1 g L -1 catalyst loading and 4 mM initial glycerol concentration, glycerol conversion and DHA selectivity were 96.8% and 17.8% in acetonitrile compared to 36.1% and 14.7% in water, respectively. The half-life of glycerol decreased by a factor of 6.2, from 467 min to 75 min, by changing the solvent from water to acetonitrile. Experiments using biodiesel-derived crude glycerol verified the effectiveness of the proposed process for the photocatalytic production of DHA from crude glycerol. A mechanism was proposed to explain the higher selectivity towards DHA over GAD in this process., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)