Boosting acetaminophen degradation in water by peracetic acid activation: A novel approach using chestnut shell-derived biochar at varied pyrolysis temperatures.

In this study, biochar derived from chestnut shells was synthesized through pyrolysis at varying temperatures from 300 °C to 900 °C. The study unveiled that the pyrolysis temperature is pivotal in defining the physical and chemical attributes of biochar, notably its adsorption capabilities and its role in activating peracetic acid (PAA) for the efficient removal of acetaminophen (APAP) from aquatic environments. Notably, the biochar processed at 900 °C, referred to as CN900, demonstrated an exceptional adsorption efficiency of 55.8 mg g-1, significantly outperforming its counterparts produced at lower temperatures (CN300, CN500, and CN700). This enhanced performance of CN900 is attributed to its increased surface area, improved micro-porosity, and a greater abundance of oxygen-containing functional groups, which are a consequence of the elevated pyrolysis temperature. These oxygen-rich functional groups, such as carbonyls, play a crucial role in facilitating the decomposition of the O-O bond in PAA, leading to the generation of reactive oxygen species (ROS) through electron transfer mechanisms. This investigation contributes to the development of sustainable and cost-effective materials for water purification, underscoring the potential of chestnut shell-derived biochar as an efficient adsorbent and catalyst for PAA activation, thereby offering a viable solution for environmental cleanup efforts.

Kumquat peel-derived biochar to support zeolitic imidazole framework-67 (ZIF-67) for enhancing peracetic acid activation to remove acetaminophen from aqueous solution.

This study presents the synthesis of a novel composite catalyst, ZIF-67, doped on sodium bicarbonate-modified biochar derived from kumquat peels (ZIF-67@KSB3), for the enhanced activation of peracetic acid (PAA) in the degradation of acetaminophen (APAP) in aqueous solutions. The composite demonstrated a high degradation efficiency, achieving 94.3% elimination of APAP at an optimal condition of 200 mg L-1 catalyst dosage and 0.4 mM PAA concentration at pH 7. The degradation mechanism was elucidated, revealing that superoxide anion (O2•-) played a dominant role, while singlet oxygen (1O2) and alkoxyl radicals (R-O•) also contributed significantly. The degradation pathways of APAP were proposed based on LC-MS analyses and molecular electrostatic potential calculations, identifying three primary routes of transformation. Stability tests confirmed that the ZIF-67@KSB3 catalyst retained an 86% efficiency in APAP removal after five successive cycles, underscoring its durability and potential for application in pharmaceutical wastewater treatment.

Hydrothermal and pyrolytic conversion of sunflower seed husk into novel porous biochar for efficient adsorption of tetracycline.

In this study, sunflower seed husk biochar prepared by ZnCl2-activated and hydrothermal carbonization (HZSF) was studied for its effectiveness in removing tetracycline (TC) from an aqueous solution. The physical and chemical properties of materials were characterized by different methods of surface analysis. The specific surface area of HZSF is significantly enhanced over 1200 times compared with non-modified biochar (HZSF: 1578.3 m2·g-1, SF-700: 1.3 m2·g-1), which has an enhancement effect on the TC adsorption capacity. The HZSF showed that the Langmuir isotherm and pseudo-second-order kinetic models could properly characterize the adsorption processes. In the Langmuir isotherm model, HZSF exhibited effective adsorption performance with qmax of 673.0 mg·g-1 at 298 K for 24 h. The possible mechanisms for the adsorption process were the monolayer, chemical adsorption, and the participation of strong intermolecular forces. In general, HZSF has the potential to be a useful adsorbent for the elimination of antibiotics from water-based solutions.

NiCo2O4-loaded sunflower husk-derived biochar as efficient peroxymonosulfate activator for tetracycline removal in water.

In this study, biochar produced from sunflower seeds husk was activated through ZnCl2 to support the NiCo2O4 nanoparticles (NiCo2O4@ZSF) in catalytic activation of peroxymonosulfate (PMS) toward tetracycline (TC) removal from aqueous solution. The good dispersion of NiCo2O4 NPs on the ZSF surface provided sufficient active sites and abundant functional groups for the adsorption and catalytic reaction. The NiCo2O4@ZSF activating PMS showed high removal efficiency up to 99% after 30 min under optimal condition ([NiCo2O4@ZSF] = 25 mg L-1, [PMS] = 0.04 mM, [TC] = 0.02 mM and pH = 7). The catalyst also exhibited good adsorption performance with a maximum adsorption capacity of 322.58 mg g-1. Sulfate radicals (SO4•-), superoxide radical (O2•-), and singlet oxygen (1O2) played a decisive role in the NiCo2O4@ZSF/PMS system. In conclusion, our research elucidated the production of highly efficient carbon-based catalysts for environmental remediation, and also emphasized the potential application of NiCo2O4 doped biochar.

Phosphoric acid-activated biochar derived from sunflower seed husk: Selective antibiotic adsorption behavior and mechanism.

In recent years, the unnecessary overuse of antibiotics has increased globally, resulting in antibiotic contamination of water, which has become a significant environmental concern. This study aims to examine the adsorption behavior of antibiotics (Tetracycline TC, Ciprofloxacin CIP, Ibuprofen IBP, and Sulfamethoxazole SMX) onto H3PO4-activated sunflower seed husk biochar (PSF). The results demonstrated that H3PO4 could enhance the specific surface area (378.8 m2/g) and create a mesoporous structure of biochar. The adsorption mechanism was investigated using kinetic models, isotherms, and thermodynamics. The maximum adsorption capacities (qmax) of TC, CIP, SMX, and IBP are 429.3, 361.6, 251.3, and 251.1 mg g-1, respectively. The adsorption mechanism of antibiotics on PSF was governed by complex mechanisms, including chemisorption, external diffusion, and intraparticle diffusion. This research provides an environmentally friendly method for utilizing one of the agricultural wastes for the removal of a variety of antibiotics from the aquatic environment.

A Clinically Oriented antimicrobial Resistance surveillance Network (ACORN): pilot implementation in three countries in Southeast Asia, 2019-2020.

Background: Case-based surveillance of antimicrobial resistance (AMR) provides more actionable data than isolate- or sample-based surveillance. We developed A Clinically Oriented antimicrobial Resistance surveillance Network (ACORN) as a lightweight but comprehensive platform, in which we combine clinical data collection with diagnostic stewardship, microbiological data collection and visualisation of the linked clinical-microbiology dataset. Data are compatible with WHO GLASS surveillance and can be stratified by syndrome and other metadata. Summary metrics can be visualised and fed back directly for clinical decision-making and to inform local treatment guidelines and national policy. Methods: An ACORN pilot was implemented in three hospitals in Southeast Asia (1 paediatric, 2 general) to collect clinical and microbiological data from patients with community- or hospital-acquired pneumonia, sepsis, or meningitis. The implementation package included tools to capture site and laboratory capacity information, guidelines on diagnostic stewardship, and a web-based data visualisation and analysis platform. Results: Between December 2019 and October 2020, 2294 patients were enrolled with 2464 discrete infection episodes (1786 community-acquired, 518 healthcare-associated and 160 hospital-acquired). Overall, 28-day mortality was 8.7%. Third generation cephalosporin resistance was identified in 54.2% (39/72) of E. coli and 38.7% (12/31) of K. pneumoniae isolates . Almost a quarter of S. aureus isolates were methicillin resistant (23.0%, 14/61). 290/2464 episodes could be linked to a pathogen, highlighting the level of enrolment required to achieve an acceptable volume of isolate data. However, the combination with clinical metadata allowed for more nuanced interpretation and immediate feedback of results. Conclusions: ACORN was technically feasible to implement and acceptable at site level. With minor changes from lessons learned during the pilot ACORN is now being scaled up and implemented in 15 hospitals in 9 low- and middle-income countries to generate sufficient case-based data to determine incidence, outcomes, and susceptibility of target pathogens among patients with infectious syndromes.