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Recycling LiCoO2 with methanesulfonic acid for regeneration of lithium-ion battery electrode materials.
No full textWith the massive consumption of lithium-ion batteries in portable consumer electronics and electric vehicles, proper disposal of spent batteries is of paramount importance for sustainable development. In this study, biodegradable organic methanesulfonic acid (MSA) is investigated for the first time to leach valuable metals from waste LiCoO2 powders for battery material regeneration. Under the optimal conditions, leaching efficiencies of lithium and cobalt are achieved at nearly ∼100% and ∼100%, respectively. Comparison experiment indicates that MSA can achieve better leaching performance than previously reported organic acids (e.g. citric acid, malonic acid, succinic acid, oxalic acid) under the same conditions. Besides, strong leaching capability of MSA at high solid-to-liquid ratios (e.g. 81.2 g L−1 and 163 g L−1) is confirmed with satisfactory leaching efficiencies (ca. 92.4%–100%). Feasibility test of MSA utilization for proper treatment of spent batteries is demonstrated at the optimized conditions. Importantly, regeneration study suggests that the as-obtained leachate can be employed to synthesize Co3O4 anode and LiCoO2 cathode materials with micro/nanostructures. Excellent cycling performance and rate capability of the regenerated electrode materials are demonstrated in the repeated charge-discharge cycles. Overall, the proposed recycling strategy is of great significance for rational resource utilization of spent lithium-ion batteries
Lignin Valorizations with Ni Catalysts for Renewable Chemicals and Fuels Productions
No full textEnergy and fuels derived from biomass pose lesser impact on the environmental carbon footprint than those derived from fossil fuels. In order for the biomass-to-energy and biomass-to-chemicals processes to play their important role in the loop of the circular economy, highly active, selective, and stable catalysts and the related efficient chemical processes are urgently needed. Lignin is the most thermal stable fraction of biomass and a particularly important resource for the production of chemicals and fuels. This mini review mainly focuses on lignin valorizations for renewable chemicals and fuels production and summarizes the recent interest in the lignin valorization over Ni and relevant bimetallic metal catalysts on various supports. Particular attention will be paid to those strategies to convert lignin to chemicals and fuels components, such as pyrolysis, hydrodeoxygenation, and hydrogenolysis. The review is written in a simple and elaborated way in order to draw chemists and engineers’ attention to Ni-based catalysts in lignin valorizations and guide them in designing innovative catalytic materials based on the lignin conversion reaction
Spatial differentiation of heritage trees in the rapidly-urbanizing city of Shenzhen, China
No full textIn China, heritage trees are actively surveyed and reported. Over 300 relevant published articles were reviewed to assess the contents, trends and geographical distributions of the investigations. The majority of the heritage trees studies in China were found in the eastern provinces and published within 2010–2014. Most studies reported surveys on all old trees. For studies focused on single species, Ginkgo (Ginkgo biloba) and Chinese Yew (Taxus chinensis) was most frequently reported. Unlike the champion tree registry in the US and other countries, the tree registry in China emphasized more on the tree age than the size. We then have studied the heritage trees in the rapidly-developed municipality of Shenzhen in South China in details. The species composition, diversity and spatial distribution were investigated using ecological indices and statistical techniques. Most trees were native with domination by Ficus microcarpa. Heritage-tree density was not correlated with land area, population density, green cover, or district development year. The oldest and youngest districts have relatively higher species diversity and tree density. It indicated the preservation of an old town plan and the creation of a new town plan conducive to accommodating pre-urbanization heritage trees. Village and forest habitats with rich tree endowments can be targeted for conservation in new urban areas. The importance of adopting a nature-friendly town plan, and the associated policies that can facilitate it, are instrumental in heritage-tree nurturing and protection. The findings can inform tree preservation and urban green infrastructure provision in fast developing cities in China and beyond
Tool of the Trade 創意廚具
Get PDFThe daily grind
好事多「磨」
When it comes to pounding powders and pastes, nothing beats the mortar and pestle
要把食材磨成粉末和醬蓉，杵臼是不二之
