Shawn D. Lin

Sustainable Hydrogen Production by Ethanol Steam Reforming using a Partially Reduced Copper–Nickel Oxide Catalyst

Hydrogen production through the use of renewable raw materials and renewable energy is crucial for advancing its applications as an energy carrier. In this study, we fabricated a solid oxide solution of Cu and Ni within a confined pore space, followed by a partial reduction, to produce a highly efficient catalyst for ethanol steam reforming (ESR). At 300 °C, EtOH is completely converted, a H2 yield of approximately 5 mol per mol is achieved, and CO2 is the main carbon-containing product. This demonstrates that H2 production from bioethanol is an efficient and sustainable approach. Such a highly efficient ESR catalyst is attributed to the ability of the metal-oxide interface to facilitate the transformation of CHx adspecies from acetaldehyde decomposition into methoxy-like adspecies, which are reformed readily to produce H2 and consequently reduce CH4 formation.

Preparation of highly dispersed catalytic Cu from rod-like CuO–CeO2 mixed metal oxides: suitable for applications in high performance methanol steam reforming

A space-confined synthesis method, using a mesoporous template to produce nano-sized copper particles (∼2 nm diameter) by the thermal hydrogen reduction (THR) of high surface area (∼105 m2 g−1) rod-like CuO–CeO2 calcined at 700 °C, is described. X-Ray diffraction (XRD) and temperature program reduction (TPR) results showed the CeO2 to be doped with Cu, thereby creating more oxygen vacancies. The excess Cu has a high degree of dispersion around 60%. Here we have used the steam reforming of methanol as a model reaction to demonstrate the capability of the materials formed and have used this as a basis of comparison with the impregnation method (carried out at 400 °C) using the same weight loading of Cu. Turnover frequency (TOF) analysis showed the rod-like CuO–CeO2 mixed oxides to have a 3 fold better catalytic performance compared to analogous materials made by the impregnation method. Additionally, we show that the incorporation of Cu atom into the surface, i.e. non-particulate, structure of CeO2 provides additional activity sites that are useful in augmenting catalytic performance.

Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst.

Summary The light irradiation parameters, including the wavelength spectrum and intensity of light source, can significantly influence a photocatalytic reaction. This study examines the propylene photo-epoxidation over V-Ti/MCM-41 photocatalyst by using artificial sunlight (Xe lamp with/without an Air Mass 1.5 Global Filter at 1.6/18.5 mW·cm−2) and ultraviolet light (Mercury Arc lamp with different filters in the range of 0.1–0.8 mW·cm−2). This is the first report of using artificial sunlight to drive the photo-epoxidation of propylene. Over V-Ti/MCM-41 photocatalyst, the propylene oxide (PO) formation rate is 193.0 and 112.1 µmol·gcat −1·h−1 with a PO selectivity of 35.0 and 53.7% under UV light and artificial sunlight, respectively. A normalized light utilization (NLU) index is defined and found to correlate well with the rate of both PO formation and C3H6 consumption in log–log scale. The light utilization with a mercury arc lamp is better than with a xenon lamp. The selectivity to PO remains practically unchanged with respect to NLU, suggesting that the photo-epoxidation occurs through the same mechanism under the conditions tested in this study.