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This study demonstrates the fabrication of high-strength, lightweight polymer-derived ceramics (PDCs) using silicon oxycarbide (SiOC)-precursor formulations with liquid crystal display (LCD) vat photopolymerization (VPP) technology. Complex geometries, such as gyroids and stochastic lattices, are successfully 3D-printed and evaluated under varying feature thicknesses and pyrolysis temperatures (800 °C and 1200 °C). Photorheology and thermogravimetric analysis (TGA) validated the efficient curing and pyrolysis characteristics of a printable precursor formulation based on vinyl methoxysiloxane homopolymer (VMM-010), which demonstrated rapid curing, low viscosity, and compatibility with LCD 3D printing, ensuring precise layering and efficient resin removal. Micro-CT scans confirmed its structural integrity and absence of voids, even in relatively thick components (≈3 mm). The VMM-based PDC lattices achieved specific compressive strengths up to 9.4 MPa g⁻¹ cm3, a 50-fold improvement over comparable lattices produced with a high-porosity SiOC PDC, and exceptional high-temperature stability, maintaining structural integrity after 2 h at 1500 °C. Compositional analysis revealed lower free carbon content and improved ceramic phase formation, driving the enhanced mechanical and thermal performance of the VMM-based ceramic. These findings underscore the scalability, reliability, and superior performance of VMM formulations for LCD 3D printing, offering new possibilities for high-performance ceramic applications in aerospace, automotive, and biomedical industries.

Metal–organic framework (MOF)-derived carbon, which contains metal nanoparticles embedded in a carbon matrix, is becoming an important group of catalysts. We report the synthesis of tungsten carbide–carbon nanocomposites using a similar concept, i.e., by pyrolysis of organotungsten compounds under high-temperature and high-pressure conditions. We characterized the product using various analytical techniques and examined its electrocatalytic activity. Two precursors, Bis(cyclopentadienyl)tungsten (IV) dichloride (Cp2WCl2) and Bis(cyclopentadienyl)tungsten (IV) dihydride (Cp2WH2) were pyrolyzed at 4.5 GPa and 600 °C. Tungsten carbide (β-WC1−x) crystals with a size of 2 nm embedded in graphitic carbon were formed from Cp2WH2-derived samples. Electrochemical measurements showed that all samples were active in the oxygen reduction reaction (ORR), with the Cp2WH2-derived sample having the best catalytic performance.

Introducing oxygen-vacancy into the surface of the non-enzymatic sensor is supposed to be an effective way to improve inherently low catalytic activity and specificity of non-enzymatic sensors. In this work, CuO/C was synthesized at different temperatures using metal-organic frameworks as sacrificial templates to receive additional content of oxygen-vacancy. The product with the highest oxygen vacancy was found at 400 °C (named CuO/C-400 °C), which increased catalytically active sites and enhanced the charge-transfer efficiency. The sensing performance was afterward explored by amperometry under an optimal applied potential at 0.5 V (vs. SCE), presenting a broad detection range from 5.0 µM to 25.325 mM (R 2  = 0.9998) with a sensitivity of 244.71 µA mM − 1  cm − 2 , and a detection limit of 1 µM. Furthermore, the reliability and selectivity of CuO/C-400 °C sensors were extensively explored in the presence of artificial serum/saliva samples with gradient glucose concentrations. The human blood samples were also detected with high recoveries compared with the clinical Hexokinase method. Hence, the prepared CuO/C-400 °C sensor with a broad detection range and high selectivity can be applied for the diabetes diagnosis ex vivo without further dilution for real-time analysis in practical applications.

Biosolids generated as byproducts of wastewater treatment processes are widely used as fertilizer supplements to improve soil condition and ultimately agricultural products yields and quality. However, biosolids may contain toxic compounds, i.e., per- and polyfluoroalkyl substances (PFAS), which can end up in soils, groundwater, and surface water, causing adverse environmental and health effects. The purpose of this study was to investigate the application of High-Temperature Pyrolysis (HTP) treatment for biosolids management, and its efficacy in eliminating PFAS from the solid fraction. Biosolid samples were pyrolyzed at two different temperatures, 500 and 700 °C, in a continuous bench-scale pyrolysis unit. The major finding is that the treatment process at higher pyrolysis temperatures can remarkably reduce or eliminate the level of PFAS (by ~97–100 wt%) in the resulting biochar samples.

This study systematically investigates the formation of NOx in the thermal decomposition of N2O, focusing on the impact of Kelvin–Helmholtz (K-H) instability in combustion environments. Using premixed CH4 co-flow flames and an electric furnace as distinct heat sources, we explored NOx emission dynamics under varying conditions, including reaction temperature, residence time, and N2O dilution rates (XN2O). Our findings demonstrate that diluting N2O around a premixed flame increases flame length and decreases flame propagation velocity, inducing K-H instability. This instability was quantitatively characterized using Richardson and Strouhal numbers, highlighting N2O’s role in augmenting oxygen supply within the flame and significantly altering flame dynamics. The study reveals that higher XN2O consistently led to increased NO formation independently of nozzle exit velocity (ujet) or co-flow rate, emphasizing the influence of N2O concentration on NO production. In scenarios without K-H instability, particularly at lower ujet, an exponential rise in NO2 formation rates was observed, due to the reduced residence time of N2O near the flame surface, limiting pyrolysis effectiveness. Conversely, at higher ujet where K-H instability occurs, the formation rate of NO2 drastically decreased. This suggests that K-H instability is crucial in optimizing N2O decomposition for minimal NOx production.

The composites were prepared by modifying silicon carbide fiber with particles of zirconium carbide (ZrC) and boron carbide (B 4 C) and incorporating them into a phenolic resin matrix. The influence of ZrC and B 4 C on the mechanical performance of SiC f /phenolic composites after high-temperature pyrolysis was studied through flexural performance test. The results show that the composite material has good thermal stability and high-temperature mechanical properties. After static ablation at 1 400 °C for 15 minutes, the flexural strength of the composite material reaches 286 MPa, which is still 7.3% higher than at room temperature, indicating that the composite material still has good mechanical properties even after heat treatment at 1 400 °C.

Carbonaceous reductants for pyrometallurgical applications are usually obtained from fossil-based sources. The most important properties of the reductants greatly depend on the application and the feeding of the reductant into the process. However, the mechanical strength, calorific value, fixed carbon content, and reactivity of the reductant are the properties that usually define the applicability of the reductant for different processes. The reactivity of the biochars is usually high in comparison to metallurgical coke, which may restrict the applicability of the biochar in reduction processes. One cause of the higher reactivity is the higher surface area of the biochars, which can be suppressed with agglomeration treatment, e.g., briquetting. In this work, hydrolysis lignin was used for slow pyrolysis experiments to produce biochars. The biochars were pyrolyzed in briquetted form and in as-received form at various temperatures. The reactivity values of the biochars were tested in dynamic reactivity tests in a CO-CO2-N2 gas atmosphere at temperatures of up to 1350 °C. It was found that the yield of the hydrolysis lignin char only decreased by 3.36 wt% when the pyrolysis temperature was elevated from 600 to 1200 °C, while a decrease in yield of 4.88 wt% occurred when the pyrolysis temperature was elevated from 450 to 600 °C. The mass loss of hydrolysis lignin biochar in the reactivity experiment in CO-CO2-N2 atmosphere was significantly decreased from 79.41 wt% to 56.80 wt% when the hydrolysis lignin was briquetted before the slow pyrolysis process and the temperature of the pyrolysis process was elevated from 600 to 1200 °C. This means that the mass loss of the material was suppressed by 22.61 wt% due to the higher pyrolysis temperature and briquetting process.

The reaction performance of producing acetylene by light cycle oil (LCO) high temperature pyrolysis was investigated with a self-made electromagnetic induction heating device. The results showed that the reaction temperature and residence time were the main factors restricting the production of acetylene during LCO high temperature cracking. When the reaction temperature was 1800 °C and the residence time was 8.24 ms, the yield of acetylene reached 7.90%. At the same time, the comparative study of different raw materials shows that Yangzhou heavy cycle oil (YZHCO) with a higher content of chain alkanes, cycloalkanes, and tetrahydro-naphthalene aromatics was beneficial to the formation of acetylene, and the highest yield of acetylene reached to 12.7%. The preliminary characterization of byproduct carbon black showed it had a good structure and could be used for lithium electron conductive agent.

This Note aims at clarifying the alternative mechanisms of carbon formation from gases at temperatures above 550 °C. Both the growth of carbon nanotubes (CNTs) by a hybrid route, and of graphene layers deposition by a pyrolytic route are analyzed: the transition had no influence in apparent kinetics, but the carbon structure was totally different. The transition temperature from hybrid to pyrolytic growth varies with the gas pressure: higher temperature transition was possible using lower active gas pressures. The rate-determining step concept is essential to understanding the behavior. In catalytic and hybrid carbon formation, the slower step controls and determines kinetics. In the pyrolytic region, the faster step dominates, and carbon bulk diffusion is blocked: layers of graphene cover the external catalyst surface. It is easier to optimize CNTs growth (rate, shape, properties) knowing the details of the alternative mechanisms operating.

We established a model for the chemical reaction kinetics of biomass pyrolysis via the high-temperature thermal cracking of liquid products. We divided the condensable volatiles into two groups, based on the characteristics of the liquid prdoducts., tar and biomass oil. The effects of temperature, residence time, particle size, velocity, pressure, and other parameters on biomass pyrolysis and high-temperature tar cracking were investigated numerically, and the results were compared with experimental data. The simulation results showed a large endothermic pyrolysis reaction effect on temperature and the reaction process. The pyrolysis reaction zone had a constant temperature period in several layers near the center of large biomass particles. A purely physical heating process was observed before and after this period, according to the temperature index curve.