We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Coconut shell activated carbon engineered for triphasic adsorption and multimechanistic removal of emerging contaminant F-53B
AI summary Read the abstract
Researchers found that coconut shell activated carbon can remove the PFAS substitute F-53B with a maximum adsorption capacity of 261.64 mg/g, achieving 99.9% removal of low concentrations within 8 hours through a combination of electrostatic interactions, hydrogen bonding, and hydrophobic forces.
A novel substitute for perfluorooctane sulfonate (PFOS), 6:2 Chlorinated polyfluoroalkyl ether acid (6:2 Cl-PFAES, F-53B), has been widely used in the electroplating and firefighting industries, raising concerns due to increasing environmental prevalence. This study systematically investigated the adsorption characteristics of F-53B by coconut shell activated carbon (CSAC) and elucidated the underlying mechanisms through adsorption kinetics, isotherm modeling, and multi-scale characterization. Results show that the maximum adsorption capacity of CSAC for F-53B reached 261.64 mg/g, with the process best described by the pseudo-second-order kinetic model (R2 > 0.97) and the Langmuir isotherm (R2 > 0.94). Intraparticle diffusion modeling revealed a three-stage adsorption sequence: surface adsorption (0-2 h), pore diffusion (2-8 h), and dynamic equilibrium (8-48 h). Solution pH influenced adsorption efficiency by regulating surface charge. Under acidic conditions (pH < point of zero charge, pHzpc = 4.49), strong electrostatic interactions between protonated CSAC surfaces and anionic F-53B resulted in an 85% removal efficiency. In contrast, alkaline conditions (pH > 7) led to a 70% reduction in adsorption efficiency (p < 0.05) due to electric repulsion. The microporous-dominated structure of CSAC (specific surface area: 857.69 m2/g; pore volume: 0.34 cm3/g) facilitated synergistic adsorption mechanisms. Oxygen-containing functional groups (C-O, -OH) promoted hydrogen bonding and hydrophobic interactions, enhancing F-53B adsorption. Besides, CSAC is optimized for emergency scenarios, it achieves 99.9% removal efficiency for 1 mg/L F-53B within 8 h at room temperature, with a maximum capacity of 261.64 mg/g; also, it maintains > 85% removal efficiency under wide pH conditions and tolerates coexisting ions (e.g., Cl-, SO42-, Ca2+).This study highlights the multi-mechanistic synergy of CSAC in theremoval of F-53B, providing theoretical foundations and technical insights for biochar-based remediation of emerging contaminants.
More Papers Like This
Effective Adsorption of Chlorinated Polyfluoroalkyl Ether Sulfonates from Wastewater by Nano-Activated Carbon: Performance and Mechanisms
AI summary Read the abstract
Three nano-activated carbons were evaluated for adsorption of chlorinated polyfluoroalkyl ether sulfonates (F-53B) from electroplating wastewater, with the best-performing carbon achieving high removal efficiency for these persistent toxic compounds.
Adsorption of Forever Chemical Pollutants: The Physical Chemistry of PFAS near Surfaces
AI summary Read the abstract
This review provides a comprehensive analysis of the physical chemistry governing how per- and polyfluoroalkyl substances (PFAS) adsorb onto solid surfaces, covering molecular interactions, thermodynamics, kinetics, and the influence of environmental variables like pH and salinity. The authors identify critical knowledge gaps that currently limit the development of effective adsorption-based remediation strategies for these persistent 'forever chemical' pollutants.
Sewage sludge biochars as effective PFAS-sorbents
AI summary Read the abstract
Researchers found sewage sludge biochars perform comparably to commercial activated carbon for PFAS removal, though competitive sorption between congeners significantly reduces effectiveness in mixed-contaminant scenarios.
Enhanced Adsorption of Bisphenol a on Lignin-Derived Biochars: Role of Thermal and Phosphoric Acid Activation in Surface Functionalization and Mechanism
AI summary Read the abstract
Researchers compared thermally and phosphoric acid-activated lignin-derived biochars for bisphenol A adsorption, finding that acid activation substantially increases surface area and introduces functional groups that enhance BPA uptake through a combination of pore filling and hydrogen bonding mechanisms.
Magnetic Biochar Adsorbent for Adsorptive Removal of Microplastics
AI summary Read the abstract
This study surveyed macro-litter on the seafloor of Montenegro's Adriatic coastal waters, documenting debris type, density, and spatial distribution through underwater observation methods. The findings contribute to Mediterranean seafloor litter monitoring efforts under EU Marine Strategy Framework Directive requirements.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.