High-temperature Pyrolysis Research Articles

Au nanoparticle-sensitized nitrogen-doped carbon applied for localized surface plasmon enhanced hydrogen evolution reaction

Carbon-supported metal nanoparticles are indispensable catalysts to enabling catalytic water splitting technologies because of their unique size-dependent properties and strong metal-support interactions. Herein, we proposed a two-step synthesis strategy, using imine-type covalent organic frameworks (COFs) as a platform to synthesize nitrogen-doped carbon-supported Au with ultra-high specific surface area through the high-temperature pyrolysis. Thanks for the polarity of imine, the growth of Au NPs in Aux/NC are ultrafine, monodispersed, and the size of Au can be precisely controlled by adjusting the amount of the metal precursor during the carbothermal reaction. Such framework structure with numerous active sites provided by the COFs renders Aux/NC ultrahigh catalytic activity and durability for hydrogen evolution reaction (HER) in acid electrolyte. Most significantly, when illumination occurs, Au5nm/NC catalyst presents a reduced HER overpotential from 416 mV to 43 mV and a shrunken charge-transfer resistance from 258 to 17 Ω, making the Au5nm/NC a promising stable catalyst for the LSPR promoted hydrogen evolution reaction.

Immobilization of Heavy Metals in Biochar Derived from Biosolids: Effect of Temperature and Carrier Gas

Slow pyrolysis was carried out in biosolids under three different temperatures (400, 500 and 600 °C) and two different carrier gases (CO2 and N2) on a fluidized bed reactor. The total concentration, chemical fractionation, and plant availability of the heavy metals in biochar were assessed by standard methods. The total concentration of Fe, Zn, Cu, Mn, Cr, Ni and Pb increased with the conversion of biosolids to biochar and with increasing pyrolysis temperature. The community’s Bureau of Reference (BCR) sequential extraction identified the migration of metals from toxic and bioavailable to potentially stable available or non-available forms at higher pyrolysis temperatures. Diethylenetriamine penta-acetic acid (DTPA)-extractable metals (Cu, Zn, Cd, Cu, Fe and Pb) were significantly lower in biochar compared to biosolids. By replacing N2 with CO2, the total metal concentration of heavy metals was significantly different for Mn, Ni, Cd, Pb and As. There were larger amounts of metals in the residual and oxidizable fractions compared to when N2 was used as a carrier gas. Consequently, the biochar produced at higher temperatures (500 and 600 °C) in the N2 environment exhibited lower potential ecological risks than in CO2 environments (69.94 and 52.16, respectively, compared to values from 75.95 to 151.38 for biochars prepared in N2). Overall, the results suggest that the higher temperature biochar can support obtaining environmentally safe biochar and can be effective in attenuating the ecological risks of biosolids.

MnNi@PVP Nanoenzyme Based on Regulating Inflammation and Immune Homeostasis for the Therapy of Inflammatory Bowel Disease.

Nanozymes exhibiting remarkable antioxidant capabilities represent an effective therapeutic approach for ulcerative colitis (UC). This study synthesized the MnNi@PVP nanoenzyme through high-temperature pyrolysis and the NaCl template method, which exhibited multienzyme activity comprising glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). This study investigated the therapeutic effect of MnNi@PVP on colitis caused by sodium dextran sulfate (DSS). The findings indicated that MnNi@PVP notably decreased the disease activity index (DAI) score, which encompasses weight loss, colon shortening, and histopathological changes. MnNi@PVP showed effectiveness in addressing oxidative damage and suppressing the levels of proinflammatory markers, such as tumor necrosis factor (TNF-α), inducible nitric oxide synthase (iNOS), and interleukin (IL)-6, by inactivating the TLR4 pathway and macrophages. In addition, MnNi@PVP demonstrated the ability to repair tight junction proteins (occludin and ZO-1) and restore the intestinal barrier. The transcriptome sequencing demonstrated that MnNi@PVP could regulate inflammatory factor expression pathways and immune processes. Additionally, negatively charged MnNi@PVP can selectively bind to inflamed colonic tissues through electrostatic interactions, endowing it with targeted reparative capabilities at the location of intestinal inflammation. The MnNi@PVP, which possesses the reactive oxygen and nitrogen species (RONS) clearance capability examined in this section, is expected to provide the basis for the targeted repair of intestinal function.

Supported Nickel Nanoparticles as Catalyst in Direct sp3 C-H Alkylation of 9H-Fluorene Using Alcohols as Alkylating Agent.

Herein, we report an inexpensive first-row transition metal Ni heterogeneous catalytic system for the Csp3-mono alkylation of fluorene using alcohols as alkylating agents via borrowing hydrogen strategy. The catalytic protocol displayed versatility with high yields of the desired products using various types of primary alcohols, including aryl/hetero aryl methanols, and aliphatic alcohols as alkylating agents. The catalyst Ni NPs@N-C was synthesized via high-temperature pyrolysis strategy, using ZIF-8 as the sacrificial template. The Ni NPs@N-C catalyst was characterized by XPS, HR-TEM, HAADF-STEM, XRD and ICP-MS. The catalyst is stable even in the air at room temperature, displayed excellent activity and could be recycled 5 times without appreciable loss in its activity.

Fluorine-Doping Carbon-Modified Si/SiOx to Effectively Achieve High-Performance Anode.

To address the significant challenges encountered by silicon-based anodes in high-performance lithium-ion batteries (LIBs), including poor cycling stability, low initial coulombic efficiency (ICE), and insufficient interface compatibility, this work innovatively prepares high-performance Si/SiOx@F-C composites via in situ coating fluorine-doping carbon layer on Si/SiOx surface through high-temperature pyrolysis. The Si/SiOx@F-C electrodes exhibit superior LIB performance with a high ICE of 79%, exceeding the 71% and 43% demonstrated by Si/SiOx@C and Si/SiOx, respectively. These electrodes also show excellent rate performance, maintaining a capacity of 603 mAhg-1 even under a high current density of 5000 mAg-1. Notably, the Si/SiOx@F-C electrode sustains a high reversible capacity of 829 mAh g-1 at 1000mA g-1 over 1400 cycles, and 588 mAhg-1 at 3000 mAg-1 even over 2400 cycles, capacity retention of up to 82.12%. Comprehensive characterization and analysis of the fluorine-doped carbon layer reveal its role in enhancing electrical conductivity and preventing structural degradation of the material. The abundant fluorine in the coating layer significantly increases the LiF concentration in the solid electrolyte interface (SEI) film, improving interfacial compatibility and overall lithium storage performance. This method is both straightforward and effective, providing a promising blueprint for the broader application of Si-based anodes in advanced lithium batteries.

Precise Synthesis of Dual-Single-Atom Electrocatalysts through Pre-Coordination-Directed in Situ Confinement for CO2 Reduction.

Dual-single-atom catalysts (DSACs) are the next paradigm shift in single-atom catalysts because of the enhanced performance brought about by the synergistic effects between adjacent bimetallic pairs. However, there are few methods for synthesizing DSACs with precise bimetallic structures. Herein, a pre-coordination strategy is proposed to precisely synthesize a library of DSACs. This strategy ensures the selective and effective coordination of two metals via phthalocyanines with specific coordination sites, such as -F- and -OH-. Subsequently, in situ confinement inhibits the migration of metal pairs during high-temperature pyrolysis, and obtains the DSACs with precisely constructed metal pairs. Despite changing synthetic parameters, including transition metal centers, metal pairs, and spatial geometry, the products exhibit similar atomic metal pairs dispersion properties, demonstrating the universality of the strategy. The pre-coordination strategy synthesized DSACs shows significant CO2 reduction reaction performance in both flow-cell and practical rechargeable Zn-CO2 batteries. This work not only provides new insights into the precise synthesis of DSACs, but also offers guidelines for the accelerated discovery of efficient catalysts.

Advanced nano-composite coatings of ZrB₂/ZrC/SiC on carbon fibers via eco-friendly precursor synthesis

This study presents a comprehensive investigation into the synthesis and characterization of ZrB2/ZrC/SiC composite coatings on carbon fiber substrates via a solution-based process followed by high-temperature pyrolysis. The precursor solution was prepared using Gum Ghatti (GG), zirconyl chloride, tetraethyl orthosilicate, and boric acid. Optimization of precursor concentration and molar ratios was performed to achieve suitable viscosity and composition. The pyrolysis process was conducted in an argon atmosphere, resulting in the formation of well-defined ZrB2, ZrC, and SiC phases. XRD analysis confirmed the phase composition, while SEM imaging revealed spheroidal particle aggregates with a uniform distribution of composite phases. TG-DTA analysis reveals the thermal decomposition behavior, highlighting distinct stages of mass loss and phase transformations. Coated carbon fibers exhibited enhanced oxidation resistance, as evidenced by TGA analysis. SEM analysis confirmed the uniform distribution and adhesion of the composite matrix on the carbon fiber substrate. This study demonstrates the successful synthesis of ZrB2/ZrC/SiC composite coatings with promising thermal properties for advanced applications.

Formation mechanism of soot in pyrolysis of 2-methylfuran under high temperature based on ReaxFF molecular dynamics simulation

In this study, the detailed mechanism of soot formation under high temperature pyrolysis of 2-methylfuran (2-MF) has been investigated by using Reactive force field molecular dynamics (ReaxFF MD) simulation. The MD analysis shows that 2-MF undergoes ring cleavage and the removal of CO/HCO/CH2CO/CH3CO, which results in the production of the C2-C4 species, promoting the formation of the initial ring molecules. The clustering of hydrocarbons by radical-chain reaction (CHRCR) mechanism plays a significant role in the mass growth of both polycyclic aromatic hydrocarbons (PAHs) and initial soot particles. The main contributors to this process are C2H2 and resonance-stabilized free radicals of C3 and C4. The H-abstraction-C2H2-addition (HACA) mechanism is important for the formation of surface active sites for PAHs and initial soot to some extent. In addition, the soot formation capacity of 2,5-dimethylfuran (25DMF) and 2-MF are compared. Under the same simulation conditions, 25DMF exhibits a higher capacity to form soot. Compared with 2-MF, 25DMF pyrolysis forms more ring-containing species at the initial stage, particularly cyclopentadiene and its derivatives. These compounds have the ability to promote the formation of PAHs, thus providing further support to the experimental-based theory.

Deep Eutectic Solvent and Molten Salt-Assisted Construction of Wheat Straw-Derived N/O Co-Doped Porous Carbon for Flexible Zinc-Air Batteries.

As a common biomass resource, wheat straw is gradually being derived as carbon materials for oxygen reduction reaction (ORR) in zinc-air batteries (ZABs). Herein, the wheat straw-derived carbon was prepared by ball milling and pyrolysis using deep eutectic solvent (DES) as the medium, which avoided the cumbersome procedures. The hydrogen bond of DES was utilized to reconstructed into a hydrogen bond network structure between DES and lignin/cellulose/hemicellulose of wheat straw. The hydrogen bond network structure was converted into N/O co-doped porous carbon (N/O-WSPC) with abundant N/O co-doped sites after high-temperature pyrolysis. Meanwhile, KHCO3 was employed to further generate hierarchical pore structures and increase the specific surface area of the N/O-WSPC. The N/O co-doped sites provided intrinsic ORR activity, while the porous structure facilitates the mass transfer effect. Therefore, the N/O-WSPC exhibited a half-wave potential of 0.87 V (vs. RHE) and a limiting current density of 5.98 mA cm-2 for ORR. The N/O-WSPC-based flexible ZAB displayed an energy density of 652.23 Wh kg-1 and a charging-discharging cycle duration for over 19 h. The DES-assisted strategy facilitates the sustainable and efficient application of wheat straw-derived carbon materials in energy storage and conversion devices.

Cu-NC single-atom nanozymes with peroxidase-like activity for colorimetric detection of d-penicillamine

Most conventional nanozymes have poor specificity and low activity, and designing high-performance nanozymes remains a challenge. In contrast, single-atom nanozymes have high atom utilization and high reactivity. Here, we prepared Cu single-atom nanozymes (Cu-NC) with excellent peroxidase-like activity by high-temperature pyrolysis using Cu as a transition metal source. The introduction of Cu formed the Cu-Nx active site, which accelerated charge transfer between the reactants and the active site and was the key for improving the activity. With Cu-NC as a catalyst, H2O2 rapidly oxidized 3,3′,5,5′-tetramethylbenzidine (TMB) to oxTMB, and the solution turned blue with strong absorption at 652 nm. Because d-penicillamine (D-PA) can reduce oxTMB or react with reactive oxygen species radicals to inhibit the color reaction, we built a colorimetric sensing platform around Cu-NC for the determination of D-PA and successfully used it for the determination of D-PA in urine samples. This work provides new ideas for the design of high-performance nanozymes and the detection of D-PA in real environments.

Assessment of heavy metals distribution and environmental risks in biochar from co-pyrolysis of sewage sludge and mixed municipal waste.

The substantial heavy metal concentrations in sewage sludge (SS) from wastewater treatment pose environmental risks and limit its practical applications. To mitigate this, SS was co-pyrolyzed with mixed municipal waste (MMW), and the heavy metals (HMs) distribution in the resulting biochar and leachate was analyzed through ICP-MS. Ecological risk (Er) and geological accumulation index (Igeo) were evaluated for various blending ratio. Results showed that MMW biochar exhibited high carbon and low sulfur content, indicating potential for carbon sequestration and soil enhancement. Both biochar showed intricate pore structures, with a slight increase in surface area, and greater aromaticity observed with the addition of MMW. Pyrolysis concentrated HMs in SS biochar, but enhanced stability reduced their leachate levels. Adding MMW decrease the level of HMs in biochar and leachate, notably reducing Se leaching from 1.54% to 0.12% and slightly lowering Hg and Cu levels. Co-pyrolysis stabilized Se by combining it with organic matter. Er analysis indicated a reduction in Hg and Cd risks by 86.6 and 41.23, respectively, with cumulative ecological risk (RI) dropping from 339.7 to 175.7. Higher MMW ratios reduced Igeo values for Zn, Cd, and Cu, shifting risks from strong to moderate and improving biochar’s agricultural suitability. High Cu and Zn levels in SS, originating from zinc and copper pipes in water treatment, were mitigated by MMW blending. Hence, the optimal co-pyrolysis ratio for HMs immobilization and SS disposal is 50% MMW. These results emphasize the importance of co-pyrolysis to produce safe biochar with reduced ecological risks. However, further research is required to optimize co-pyrolysis for various sludge types at higher pyrolysis temperatures (beyond 400℃) with the application of acid leaching agents.

Effect of pyrolysis temperature on the physical and chemical characteristics of pine wood biochar

Biochar is a useful bioproduct with a wide range of promising applications. The main objective of this study is to investigate the effect of pyrolysis temperatures on the physicochemical properties of biochar produced from pine wood using a slow pyrolysis methodology. Fourier transfer infrared (FTIR) spectroscopy analysis uncovered that the biochar synthesized at the different temperatures selected possessed distinct functional groups. The elemental analysis confirmed that an increase in pyrolysis temperature led to a rise in the carbon (C) concentration, whereas conversely there is a reciprocal decrease in the levels of oxygen (O) and hydrogen (H). Consequently, biochar produced at high temperatures showed low (O/C) and (H/C) fractions. Surface area (gas adsorption) studies indicated that the biochar surface area and pore volume increase at higher pyrolysis temperature. In contrast, the pore size was found to decrease at high temperatures. It was found that increased pyrolysis temperature resulted in reduced biochar yield. Biochar for use in specific applications like as an adsorbent material is ultimately influenced by the pyrolysis temperature. Therefore, it can be concluded that the results of the current study enhances the understanding on the effect of pyrolysis temperature on biochar synthesis and how different parameters can be used to tailor the material characteristics for specific applications.

Pyrrolic and pyridinic nitrogen-rich carbon microspheres derived from polydopamine as advanced anodes for sodium ion batteries

This study presents an efficient approach for designing hard carbon electrodes through the synthesis of nitrogen-doped carbon microspheres (NCS) via an eco-friendly high-temperature pyrolysis of polydopamine. By precisely modulating the pyrolysis temperature, the nitrogen content and bonding configurations are carefully optimized. NCS treated at 1000 °C demonstrate exceptional electrochemical performance, including an initial Coulombic efficiency of 73.4 %, a reversible capacity of 386.6 mA h g−1, a rate capability of 180.1 mA h g−1 at 10 A g−1, and 75.3 % capacity retention after 1500 cycles. The abundant pyrrolic-N dopants effectively expand interlayer spacing, facilitating efficient and reversible Na⁺ intercalation. Additionally, pyridinic-N and pyrrolic-N functionalities significantly increase surface defect density, promoting rapid electron and ion transport. The spherical morphology, characterized by a low surface area, further reduces irreversible Na⁺ consumption during solid electrolyte interphase (SEI) formation, thereby ensuring high initial coulombic efficiency (ICE).

Ball Milling and Magnetic Modification Boosted Methylene Blue Removal by Biochar Obtained from Water Hyacinth: Efficiency, Mechanism, and Application.

Ball milling is a feasible and promising method of biochar modification that can significantly increase its adsorption ability to methylene blue (MB). This study synthesized nine biochars derived from water hyacinth under different pyrolysis temperatures and modified with ball milling and Fe3O4. The structural properties of the pristine and ball-milled magnetic biochars were investigated and employed to adsorb MB. The results showed that ball milling significantly enhanced the specific surface area, total pore volume, and C-, N-, and O-containing groups of biochars, especially in low-temperature pyrolysis biochars. The Langmuir isotherm and the pseudo-secondary kinetic model fitted well with the MB adsorption process on biochars. After ball-milled magnetic modification, the adsorption capacity of biochar at 350 °C for MB was increased to 244.6 mg g-1 (8-fold increase), owing to an increase in accessible functional groups. MB removal efficiencies by low-temperature pyrolysis biochars were easily affected by pH, whereas high-temperature pyrolysis biochars could effectively remove MB in a wide pH range. WQM1, with the high adsorption capacity and stability, provided the potential to serve as an adsorbent for MB removal. Based on DFT calculations, the chemisorption and electrostatic interactions were the primary mechanism for enhancing MB removal with ball-milled magnetic biochar at low-temperature pyrolysis, followed by H-bonding, π-π interaction, hydrophobic interaction, and pore filling.

Metal-modified biochars prepared from blue algae and their ability of adsorbing phosphates from water and utilization as soil amendment

The problem of blue algae accumulation can be alleviated by utilizing blue algae as biomass for resource utilization, which can remove excess phosphates from water to alleviate eutrophication. Herein, Magnesium (Mg) and/or lanthanum (La) were used to modify biochar via high-temperature slow pyrolysis with blue algae as the raw biomass. These modified biochars exhibited abundant carbon (18.0 %-50.3 %), oxygen content (17.4 %-49.1 %), along with a high specific surface area (82.26–233.80 m2/g). The surface of metal-modified biochar was enriched with hydroxyl and carboxyl groups and metal elements were efficiently incorporated into biochars. Adsorption kinetic and isotherm experiments were conducted under the optimal pyrolysis temperature of 600 °C, pH of 6.0, and adsorbent dosage of 2.0 g/L. The adsorption kinetics studies by metal-modified biochars for phosphate fitted well pseudo-second-order model Redlich-Peterson isotherm model. Biochar modified by Mg and La exhibited the highest removal efficiency (97.8 %) for phosphate at adsorption equilibrium. The adsorption mechanism involved the electrostatic interaction between hydroxylated metal oxides and negatively charged phosphate ions and the precipitation of phosphate ions through chemical reactions with metal oxides in the solution. After phosphate adsorption, the pristine and metal-modified biochars derived from blue algae were applied as the soil amendment. Biochar adsorbed phosphate apparently improved the germination rate of seeds facilitated the height, width, weight, and chlorophyll content of vegetable seedlings, and induced oxidative stress, which proved that the biochar recovered after adsorption was a high-quality soil amendment. This study provides a new approach for the treatment of phosphate wastewater and the algae application.

MoS2/N-doped hollow carbon foam for thermal insulation and broadband electromagnetic wave absorption

In this study, we demonstrated the synthesis of MoS2/N-doped hollow carbon foam (MoS2/NCF) for high performance of electromagnetic wave absorption (EMA), through high-temperature pyrolysis melamine foam and hydrothermal reaction. By adjusting the electromagnetic parameters of N-doped hollow carbon foam (NCF) through MoS2 nanosheets, the effective absorption bandwidth of MoS2/NCF reached 9.62 GHz at the matching thickness was 2.3 mm. Radar cross section (RCS) simulation results demonstrated that MoS2/NCF exhibited a strong reduction ability of RCS. At room temperature, the composite MoS2/NCF could block radiation temperature of around 110 ℃ in the case of a thickness of only 7 mm and a heating plate at 200 ℃. Moreover MoS2/NCF exhibited thermal stability and a certain flame retardants ability. The result indicated that the composite MoS2/NCF was beneficial for its application in the fields of thermal insulation and electromagnetic wave absorption.

High temperature pyrolysis of sewage sludge: Synergistic effects of co-pyrolysis with rice straw and composite plastics wastes

The synergistic effect of co-pyrolysis for the mixtures of sewage sludge (SS), rice straw (RS) and composite plastic wastes (PE&PP) has been investigated with the aim of high gas yields and hydrogen generation. In this context, the applicability of high temperature pyrolysis technology was evaluated at both rotary type batch reactor and rotating screw type continuous reactor operating under the industrially relevant conditions. Gas yields have been improved at increasing the operating temperatures up to 850 °C. The gas yield of 75.06 % with its H2 portion of 32.35 % has been achieved as the best results for continuous pyrolysis unit at pilot scale. Secondary reactions such as steam de-alkylation, steam cracking, water gas shift and so on were regarded as being responsible for the high gas yields when the primary products of pyrolysis, i.e. condensable vapors, were much exposed to the hot zones inside the reactor. The dehydration of organic components involving the loss of water may supply steam to create a reactive pyrolysis atmosphere. While the pyrolysis of sewage sludge and rice straw favors CO and CO2 formation due to the high oxygen contents of these feedstocks, more methane and light olefins were produced when the plastics were added to the feedstock blends. This was ascribed to the initially generated radicals from the decomposition of sewage sludge and/or rice straw that might promote the scission reactions of plastics towards volatiles. It was shown that high temperature pyrolysis can be applied to a variety of organic wastes such as rice straw, sewage sludge and waste plastics. Conversion of wastes to hydrogen fosters the circular economy by putting the disposal costs down and creates a new route on renewable hydrogen generation.

Biomass-Derived-Carbon-Supported Spinel Cobalt Molybdate as High-Efficiency Electrocatalyst for Oxygen Evolution Reaction.

Ananas comosus leaves were converted to a porous graphitized carbon (GPLC) material via a high-temperature pyrolysis method by employing iron salt as a catalyst. A cobalt molybdate (CoMoO4)-and-GPLC composite (CoMoO4/GPLC) was then prepared by engineering CoMoO4 nanorods in situ, grown on GPLC. N2 adsorption-desorption isothermal curves and a pore size distribution curve verify that the proposed composite possesses a porous structure and a large specific surface area, which are favorable for charge and reactant transport and the rapid escape of O2 bubbles. Consequently, the as-synthesized CoMoO4/GPLC shows low overpotentials of 289 mV and 399 mV to afford the current densities of 10 mA cm-2 and 100 mA cm-2 towards the oxygen evolution reaction (OER), which is superior to many CoMoO4-based catalysts in previous studies. In addition, the decrease in current density is particularly small, with a reduction rate of 3.2% after a continuous OER procedure for 30 h, indicating its good stability. The excellent performance of the CoMoO4/GPLC composite proves that the GPLC carrier can obviously impel the catalytic activity of CoMoO4 by improving electrical conductivity, enhancing mass transport and exposing more active sites of the composite. This work provides an effective strategy for the efficient conversion of waste ananas comosus leaves to a biomass-derived-carbon-supported Co-Mo-based OER electrocatalyst with good performance, which may represent a potential approach to the development of new catalysts for OER, as well as the treatment of waste biomass.

A recyclable and high porosity vinasse-based biochar with enhanced superficial active sites for antibiotics recovery

Antibiotic pollution in water bodies is a global environmental issue. For adsorbing antibiotic residues, biochar produced by direct high temperature pyrolysis faces challenges in balancing adsorption capacity and recyclability due to limited active sites. Thus, a recyclable and high-porosity vinasse-based biochar was developed via co-pyrolysis of K2FeO4 one-pot method. The co-pyrolysis biochar's surface area was augmented by 143 times, from 3.4 m²/g to 490.9 m²/g. The maximum theoretical adsorption capacity of the co-pyrolysis biochar for norfloxacin (NOR) increased from 4.4 mg/g to 364.9 mg/g, an approximate 83-fold enhancement. The surface of the biochar was rich in active groups (C-O, C-Fe, and -OH), which acted as the active sites to enhance the adsorption of NOR. The adsorption mechanism involved a variety of interactions, including pore-filling, hydrogen bond, π-π interactions, surface complexation, and electrostatic interactions. Importantly, the biochar is magnetic and can be recycled attributed to the generation of ferriferous oxides during the carbonization. After three cycles of reuse, the adsorption efficiency of vinasse-based biochar for NOR still exceeded 70 %. Such biochar prepared by this facile and feasible co-pyrolysis method show the potential to enhance active sites for removal of antibiotic from aquatic systems.

Removal of cefuroxime from aqueous solution by biochars derived from antibiotic mycelial residue.

In China, antibiotic mycelial residue is categorized as hazardous waste. To achieve the harmless and resourceful disposal of cephalosporin, three types of biochars from cephalosporin mycelia residues, namely non-activated carbon (BC1), ZnCl2-activated carbon (BC2), and KOH-activated carbon (BC3), were respectively fabricated by high-temperature pyrolysis carbonization technology. These three kinds of biochars were characterized via iodine value, FTIR, and SEM, and the adsorption performance of the prepared biochars was investigated using cefuroxime (CXM) as the adsorption target. The results indicated that BC3 biochar possesses the most well-developed pores and the highest iodine value of 1367.41 mg/g; The most suitable dosage is 1.6 g/L, and the lower the pH, the more favorable the adsorption effect. The investigation of adsorption kinetics revealed that it conformed to the kinetic model of pseudo-second order, as well as the process of adsorption was governed by the chemical adsorption mechanism, the rate of adsorption was affected by the collective impact of the quantity of active sites present and the interaction strength between the CXM molecules and the biochar. The exploration of adsorption thermodynamics revealed that it aligned with the Langmuir model, the surface of biochar was relatively uniform, and the adsorption was mainly of low coverage; The calculation of thermodynamic parameters demonstrated that the adsorption was exothermic and spontaneous.