Ultra-fast green synthesis of a defective TiO photocatalyst towards hydrogen production.

An ultra-fast green synthesis of defective titanium dioxide (TiO) photocatalysts was conducted by the microwave-assisted method using l-ascorbic acid (l-As) as a reducing agent. Effect of l-As concentrations on the chemical-, optical- and photoelectrochemical properties as well as the photocatalytic performance towards the hydrogen (H) production was explored. The obtained TiO nanoparticles (NPs) illustrated the brown fine powders with different brownness levels depending on the concentrations of l-As.

Highly efficient ZnO/WO nanocomposites towards photocatalytic gold recovery from industrial cyanide-based gold plating wastewater.

Discharging the gold-contained wastewater is an economic loss. In this work, a set of ZnO/WO was facile synthesized by hydrothermal method in order to recover gold from the industrial cyanide-based gold plating wastewater by photocatalytic process. Effect of ZnO contents coupled with WO was first explored.

Innovative metal oxides (CaO, SrO, MgO) impregnated waste-derived activated carbon for biohydrogen purification.

In this work, a series of innovative metal oxide impregnated waste-derived activated carbons (MO/AC) was synthesized and used to purify the simulated biohydrogen based on the concept of CO removal from the gas stream. Effects of metal oxide types (CaO, SrO and MgO) and contents of the best metal oxides on the morphology and the CO adsorption capacity from the biohydrogen were investigated. It was found that both metal oxide types and contents played an important role on the adsorbent textural property and surface chemistry as well as the CO adsorption capacity.

Photosynthesis of Au/TiO nanoparticles for photocatalytic gold recovery from industrial gold-cyanide plating wastewater.

A series of Au/TiO nanoparticles (NPs) with different gold loadings (x = 0.1-1.0 wt%) was synthesized by the photodeposition and then employed as photocatalysts to recover precious component from the industrial gold-cyanide plating wastewater.

Valorization of spent disposable wooden chopstick as the CO adsorbent for a CO/H mixed gas purification.

A series of activated carbons (ACs) derived from spent disposable wooden chopsticks was prepared via steam activation and used to separate carbon dioxide (CO) from a CO/hydrogen (H) mixed gas at atmospheric pressure. A factorial design was employed to investigate the effects of the activation temperature and time as well as their interactions on the production yield of ACs and their CO adsorption capacity. The activation temperature exhibited a much higher impact on both the production yield and the CO adsorption capacity of ACs than the activation time.

Photocatalytic Recovery of Gold from a Non-Cyanide Gold Plating Solution as Au Nanoparticle-Decorated Semiconductors.

In this work, a photocatalytic process was carried out to recover gold (Au) from the simulated non-cyanide plating bath solution. Effects of semiconductor types (TiO, WO, NbO, CeO, and BiO), initial pH of the solution (3-10), and type of complexing agents (NaSO and NaSO) and their concentrations (1-4 mM each) on Au recovery were explored. Among all employed semiconductors, TiO exhibited the highest photocatalytic activity to recover Au from the simulated spent plating bath solution both in the absence and presence of complexing agents, in which Au was completely recovered within 15 min at a pH of 6.

Application of magnetic field to CO hydrogenation using a confined-space catalyst: effect on reactant gas diffusivity and reactivity.

An external magnetic field has recently been applied in reaction processes to promote movement and avoid agglomeration of magnetic particles, and also reduce the activation energy through improving the gas-solid contact. In this work, the effect of an external magnetic field on reactant gas diffusivity and reactivity in CO hydrogenation within a confined-space catalyst was investigated for the first time using a conventional reactor packed with a bimetallic 5Fe-5Co/ZSM-5 molecular sieve catalyst. The synergistic effect between magnetic field and limited mass transfer within zeolite cavities improved the mass transfer ability and reaction phenomena of the reactant molecules, leading to enhancement of catalytic activity with tailored reaction pathways.