A B S T R A C TThe use of Ni-Fe catalysts for the catalytic pyrolysis of real-world waste plastics to produce hydrogen and high value carbon nanotubes (CNT), and the influence of catalyst composition and support materials has been investigated. Experiments were conducted in a two stage fixed bed reactor, where plastics were pyrolysed in the first stage followed by reaction of the evolved volatiles over the catalyst in the second stage. Different catalyst temperatures (700, 800, 900°C) and steam to plastic ratios (0, 0.3, 1, 2.6) were explored to optimize the product hydrogen and the yield of carbon nanotubes deposited on the catalyst. The results showed that the growth of carbon nanotubes and hydrogen were highly dependent on the catalyst type and the operational parameters. Fe/ γ-Al 2 O 3 produced the highest hydrogen yield (22.9 mmol H 2 /g plastic ) and carbon nanotubes yield (195 mg g −1 plastic ) among the monometallic catalysts, followed by Fe/α-Al 2 O 3 , Ni/γ-Al 2 O 3 and Ni/α-Al 2 O 3 . The bimetallic Ni-Fe catalyst showed higher catalytic activity in relation to H 2 yield than the monometallic Ni or Fe catalysts because of the optimum interaction between metal and support. Further investigation of the influence of steam input and catalyst temperature on product yields found that the optimum simultaneous production of CNTs (287 mg g −1 plastic ) and hydrogen production (31.8 mmol H 2 /g plastic ) were obtained at 800°C in the absence of steam and in the presence of the bimetallic Ni-Fe/γ-Al 2 O 3 catalyst.

10To explore the mechanism of the influence of Ni-Fe bimetallic catalyst for the 11 producing high-value carbon nanotubes (CNTs) with clean hydrogen from waste 12 plastic pyrolysis, the pyrolysis-catalysis of plastics were performed using a two stage

Lithium‐ion battery manufacturing chain is extremely complex with many controllable parameters especially for the drying process. These processes affect the porous structure and properties of these electrode films and influence the final cell performance properties. However, there is limited available drying information and the dynamics are poorly understood due to the limitation of the existing metrology. There is an emerging need to develop new methodologies to understand the drying dynamics to achieve improved quality control of the electrode coatings. A comprehensive summary of the parameters and variables relevant to the wet electrode film drying process is presented, and its consequences/effects on the finished electrode/final cell properties are mapped. The development of the drying mechanism is critically discussed according to existing modeling studies. Then, the existing and potential metrology techniques, either in situ or ex situ in the drying process are reviewed. This work is intended to develop new perspectives on the application of advanced techniques to enable a more predictive approach to identify optimum lithium‐ion battery manufacturing conditions, with a focus upon the critical drying process.

The production of high-value carbon nanotubes and hydrogen from the two-stage pyrolysis catalytic-steam reforming/gasification of waste tires have been investigated. The catalysts used were Co/Al2O3, Cu/Al2O3, Fe/Al2O3 and Ni/Al2O3. The pyrolysis temperature and catalyst temperature were 600 °C and 800 °C, respectively. The fresh catalysts were analysed by temperature programmed reduction and X-ray diffraction. The product gases, including hydrogen were analysed by gas chromatography and the carbon nanotubes characterized by scanning and transmission electron microscopy and Raman spectrometry. The results showed that the Ni/Al2O3 catalyst produced high quality multiwalled carbon nanotubes along with the highest H2 yield of 18.14 mmol g -1 tire, compared with the other catalysts, while the Co/Al2O3 and Cu/Al2O3 catalysts produced lower hydrogen yield, which is suggested to be associated with the formation of amorphous type carbons on the surface of the Co/Al2O3 and Cu/Al2O3 catalysts.

A range of process conditions have been investigated to maximise the production of carbon nanotubes (CNTs) and/or hydrogen from waste tyres. A two-stage pyrolysis-catalytic reactor system was used and the influence of catalyst temperature (700, 800 and 900 °C), tyre: catalyst ratio (1:0.5, 1:1 and 1:2) and steam input (water injection 0, 2 and 5 ml h -1 ) to the second catalyst stage were investigated. The catalyst used was a Ni/Al2O3 catalyst prepared by a wetness impregnation technique. Carbon was deposited on the catalyst surface during pyrolysis-catalysis increasing with increasing catalyst temperature and also increasing as the tyre: catalyst ratio was raised. Examination of the carbon showed it to be composed of largely filamentous type carbons, producing 253.7 mg g -1 tyre of filamentous carbons at a tyre: catalyst ratio of 1:1 and catalyst temperature of 900 °C. A significant proportion of the deposited filamentous carbons were multi-walled carbon nanotubes as shown by transmission electron microscopy characterisation. The introduction of steam to the process enhanced hydrogen production, producing a maximum of 34.69 mmol g -1 tyre at a water injection rate of 5 ml h -1 .4

Aqueous zinc-ion batteries with Zn metal anodes are promising candidates for future electrochemical energy storage devices. However, Zn dendrite growth greatly limits their practical application. Many recent studies have developed...

The electrode drying process is a crucial step in the manufacturing of lithium-ion batteries and can significantly affect the performance of an electrode once stacked in a cell. High drying rates may induce binder migration, which is largely governed by the temperature. Additionally, elevated drying rates will result in a heterogeneous distribution of the soluble and dispersed binder throughout the electrode, potentially accumulating at the surface. The optimized drying rate during the electrode manufacturing process will promote balanced homogeneous binder distribution throughout the electrode film; however, there is a need to develop more informative in situ metrologies to better understand the dynamics of the drying process. Here, ultrasound acoustic-based techniques were developed as an in situ tool to study the electrode drying process using NMC622-based cathodes and graphite-based anodes. The drying dynamic evolution for cathodes dried at 40 and 60 °C and anodes dried at 60 °C were investigated, with the attenuation of the reflective acoustic signals used to indicate the evolution of the physical properties of the electrode-coating film. The drying-induced acoustic signal shifts were discussed critically and correlated to the reported three-stage drying mechanism, offering a new mode for investigating the dynamic drying process. Ultrasound acoustic-based measurements have been successfully shown to be a novel in situ metrology to acquire dynamic drying profiles of lithium-ion battery electrodes. The findings would potentially fulfil the research gaps between acquiring dynamic data continuously for a drying mechanism study and the existing research metrology, as most of the published drying mechanism research studies are based on simulated drying processes. It shows great potential for further development and understanding of the drying process to achieve a more controllable electrode manufacturing process.

Thermo-chemical conversion of carbonaceous wastes such as tyres, plastics, biomass and crude glycerol is a promising technology compared to traditional waste treatment options (e.g. incineration and landfill). The process promotes...