Industrial and mining wastewater, along with copper tailings, are typically highly acidic and contain copper and other heavy metals, which may contaminate and damage the environment. Copper (Cu) is, however, a valuable metal, making its removal and recovery from such wastewater and tailings environmentally and economically advantageous. Chelating ion exchange resins featuring bis-picolylamine functional groups are especially suitable for application requiring selective recovery of Cu(II) from highly acidic media.
View Article and Find Full Text PDFA wide array of carbon materials finds extensive utility across various industrial applications today. Nonetheless, the production processes for these materials continue to entail elevated temperatures, necessitate the use of inert atmospheres, and often involve the handling of aggressive and toxic chemicals. The prevalent method for large-scale carbon material production, namely the pyrolysis of waste biomass and polymers, typically unfolds within the temperature range of 500-700 °C under a nitrogen (N) atmosphere.
View Article and Find Full Text PDFThe conversion of biomass and natural wastes into carbon-based materials for various applications such as catalysts and energy-related materials is a fascinating and sustainable approach emerged during recent years. Precursor nature and characteristics are complex, hence, their effect on the properties of resulting materials is still unclear. In this work, we have investigated the effect of different precursors and pyrolysis temperature on the properties of produced carbon materials and their potential application as negative electrode materials in Li-ion batteries.
View Article and Find Full Text PDFUsing a set of microscopic, spectroscopic, and electrochemical methods, a detailed study of the interrelation between the structural and electrochemical properties of the as-prepared nitrogen-containing multi-walled carbon nanotubes (N-MWCNTs) and their modified derivatives is carried out. It was found that after treatment of nanotubes with hydrochloric acid, their structure is improved by removing amorphous carbon from the outer layers of N-MWCNTs. On the contrary, ion bombardment leads to the formation of vacancy-type structural defects both on the surface and in the bulk of N-MWCNTs.
View Article and Find Full Text PDFBecause the C-ON bond homolysis rate constant is an essential parameter of alkoxyamine reactivity, it is especially important to tune without a major alteration of the structure of the molecule. Recently, several approaches have become known, , protonation of functional groups and formation of metal complexes. In this paper, coordination reactions of [Zn(hfac)(HO)] with a series of new SG1-based alkoxyamines affording complexes with different structures are presented.
View Article and Find Full Text PDFAn alkoxyamine was prepared from a cyclic aldonitrone nitroxide. The resulting alkoxyamine containing an aldonitrone functional substituent is relatively stable but can react readily with vinyl monomers to form a cycloadduct that has a much higher C-ON homolysis rate. This type of in situ activation converts the aldonitrone alkoxyamine into an efficient controlling agent for nitroxide-mediated polymerization.
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