Cr(VI) is a common wastewater pollutant. Various adsorbents including carbon-based materials are used for the removal of Cr(VI) owing to their high adsorption capacity. Chemical activation is an effective method to increase the specific surface area of adsorbents and, thus, further improve their adsorption capacity. However, research on the adsorption and removal of Cr(VI) from aqueous solutions by chemically activated carbon spheres is limited. Here, glucose and sodium dodecylbenzene sulfonate were used to produce carbon spheres (CSs) via hydrothermal synthesis. Activated carbon spheres (ACSs) were then derived using KOH. The adsorption of Cr(VI) in solution by CS and ACS was investigated through batch experiments. The results indicate that the specific surface area of the ACS was 1491.21 m g, which was much higher than that of the CS. The adsorption kinetics of the sorbent was consistent with the pseudo-second-order kinetic model and the adsorption isotherm followed the Langmuir model. This indicated that the adsorption process of the ACS with respect to Cr(VI) was mainly via single molecular layer adsorption and chemisorption. In a 200 mg L Cr(VI) solution, the maximum amount of Cr(VI) adsorbed by the ACS was 230.15 mg g, and some of these adsorbed Cr(VI) were reduced to Cr(III). These results show that ACSs have strong potential for application in the removal of Cr(VI) from aqueous solutions.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.scitotenv.2020.143457 | DOI Listing |
RSC Adv
January 2025
College of Environment and Chemical Engineering, Dalian University Dalian 116622 Liaoning P. R. China
Photocatalytic technology for removing organic dye pollutants has gained considerable attention because of its ability to harness abundant solar energy without requiring additional chemical reagents. In this context, YF spheres doped with Yb, Er, Tm (YF) are synthesized using a hydrothermal method and are subsequently coated with a layer of graphitic carbon nitride (g-CN) with Au nanoparticles (NPs) adsorbed onto the surface to create a core-shell structure, designated as YF: Yb, Er, Tm@CN-Au (abbreviated as YF@CN-Au). The core-shell composites demonstrate remarkable stability, broadband absorption, and exceptional photocatalytic activity across the ultraviolet (UV) to near-infrared (NIR) spectral range.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
College of Physics and Electronic Information, Yunnan Normal University, 650500 Kunming, China. Electronic address:
Rational design of effective cathode host materials is an effective way to solve the problems of serious shuttle and slow conversion of polysulfides in lithium-sulfur batteries (LSBs). However, the redox reaction of sulfur differs from conventional "Rocking chair" type batteries and involves a cumbersome phase transition process, so a single-component catalyst cannot consistently and steadily enhance the reaction rate throughout the redox process. In this work, a hybrid composed of magnetopyrite FeS catalyst-modified with N/S-doped porous carbon spheres (FeS@NSC) is proposed as a novel sulfur host to synergistically promote the adsorption and redox catalysis conversion of polysulfides.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, Institute for Advanced Materials and Manufacturing, University of Tennessee, Knoxville, Tennessee 37996, United States.
Porous liquids have traditionally been designed with sterically hindered solvents. Alternatively, recent efforts rely on dispersing microporous frameworks in simpler solvents like water. Here we report a unique strategy to construct macroporous water by selectively incorporating hydrophilicity on the surfaces of hydrophobic hollow carbon spheres (HCS).
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Department of Chemistry, Western University, 1151 Richmond Street, London, ON, N8K 3G6, Canada.
This work addresses fundamental questions that deepen our understanding of secondary coordination sphere effects on carbon dioxide (CO) reduction using derivatized hydride analogues of the type, [Cp*Fe(diphosphine)H] (Cp* = CMe ) - a well-studied family of organometallic complex - as models. More precisely, we describe the general reactivity of [(Cp*-BR)Fe(diphosphine)H], which contains an intramolecularly positioned Lewis acid, and its cooperative reactivity with CO. Control experiments underscore the critical nature of borane incorporation for transforming CO to reduced products, a reaction that does not occur for unfunctionalized [Cp*Fe(diphosphine)H].
View Article and Find Full Text PDFFEMS Microbiol Ecol
January 2025
Center for Pan-third Pole Environment, Lanzhou University, Lanzhou, China.
In polar and alpine regions, global warming and landform changes are draining lakes, transforming them into permafrost with altered microbial communities and element cycling. In this study, we investigated bacterial and archaeal (prokaryotic) community changes in the newly exposed sediment of Zonag Lake (Tibetan Plateau), focusing on prokaryotic diversity, community structure, and genes involved in carbon fixation and nitrogen cycling across lateral (up to 800 m) and vertical (up to 80 cm) horizons. The results showed that prokaryotic richness decreased across the lateral horizons, coinciding with reductions in carbon concentrations.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!