Abstract
This work recovered Ni or Cu cations from simulated electroplating wastewater to synthesize Ni/Cu nano-catalysts for H2 generation by ethanol steam reforming (ESR). Aluminum lathe waste was used as a framework to prepare the structured catalyst. Li–Al–CO3 layered double hydroxide (LDH) was electrodeposited on the surface of the framework. The LDH was in a platelet-like structure, working as a support for the formation of the precursor of the metal catalysts. The catalytic performance and the coke properties of a 6Cu_6Ni two-stage catalyst configuration herein used for ESR catalytic reaction were studied. The Cu–Ni two-stage catalyst configuration (6Cu_6Ni) yielded more H2 (~10%) than that by using the Ni-based catalyst (6Ni) only. The 6Cu_6Ni catalyst configuration also resulted in a relatively stable H2 generation rate vs. time, with nearly no decline during the 5-h reaction. Through the pre-reaction of ethanol-steam mixture with Cu/LiAlO2 catalyst, the Ni/LiAlO2 catalyst in the 6Cu_6Ni catalyst configuration could steadily decompose acetaldehyde, and rare acetate groups, which would evolve condensed coke, were formed. The Ni nanoparticles were observed to be lifted and separated by the carbon filaments from the support and had no indication of sintering, contributing to the bare deactivation of the Ni/LiAlO2 catalyst in 6Cu_6Ni.
Highlights
Nickel plating and copper plating are often conducted in the preparation of a surface for treatment or as the final treatment of many items in everyday use [1,2]
Huang et al [27] and our previous study [17] suggested that Li–Al4–CofO233 layered double hydroxide (LDH) transferred into mixed metal oxides with low crystallinity after it was heated at 400~500 °C
A coating of Li–Al layered double hydroxide (LDH) with nano-sized platelet structure was successfully electrodeposited on the surface of aluminum lathe waste
Summary
Nickel plating and copper plating are often conducted in the preparation of a surface for treatment or as the final treatment of many items in everyday use [1,2]. Significant quantities of Ni and Cu cations are frequently present in plating wastewater. The authors’ earlier investigation [4] reviewed numerous methods for treating nickel plating and copper plating wastewater, including filtration, membrane separation, ionexchange, precipitation, adsorption, and biosorption. Studies concerning the extraction of Ni2+ and Cu2+ either from the electroplating wastewater or the rinse stream when plated workpieces are washed are very few. This work concerned a new process used to recover metal ions from simulated Ni or Cu electroplating wastewater for use in the synthesis of nano-catalysts. The use of the prepared Ni- and Cu-based catalysts in ethanol steam reforming (ESR) to produce hydrogen was investigated
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have