Heating Rate Research Articles

Assessment of the use of biochar from the slow pyrolysis of walnut and almond shells as an energy carrier

ABSTRACT This study explores the energy applications and combustion kinetics of biochar produced from walnut and almond shells through pyrolysis. Using macro-thermogravimetric analysis at heating rates of 10, 15, and 20 K min−1, a multi-step mechanism involving two parallel reactions was used to model thermal decomposition. Bioenergy indices revealed that walnut shell-based biochar (WSB) produced at 773 K and 873 K displayed superior biofuel potential due to its high energy density and low ash content, while almond shell-based biochar (ASB) at 673 K demonstrated the best overall bioenergy performance. Among the tested heating rates, 15 K min−1 provided optimal results for ignition, combustion, and burnout indices, with WSB showing the highest overall combustion performance. Kinetic analysis using the Coats-Redfern method demonstrated the highest R2 values and minimized RMSE and SSE. The activation energy for the first pseudo-component ranged from 54.91 to 129.84 kJ mol−1 for ASB and from 61.71 to 141.85 kJ mol−1 for WSB. For the second pseudo-component, the activation energy ranged from 25.21 to 159.32 kJ mol−1 for ASB and 25.63 to 96.25 kJ mol−1 for WSB. These findings emphasize the potential of WSB and ASB biochar for bioenergy applications, with WSB exhibiting the best combustion characteristics.

A novel micro ohmic heating cell for microorganism destruction kinetic studies: Performance validation

Ohmic heating cells used for microbial destruction are typically large compared with conventional capillary tubes. Limitations of commonly used large cells include large mass, high come-up-time (CUT), lack of uniform heating, and operation at atmospheric pressure. A new 3 mL Micro Ohmic Cell (MOC) was designed and fabricated for the kinetic study of microbial spore destruction. Two tiny titanium electrodes, mounted horizontally on a T-shaped cylindrical cell with a 3 cm gap, generate a rapid heating rate up to 140 °C. Fibre optic temperature sensors were used for direct temperature monitoring during CUT and holding time. Model solutions were heated under voltage gradients up to 90 V/cm. Uniform heating was achieved under stirring conditions with less than 1 °C variation across the cell volume, and the coldest spot was identified as the liquid-air interface. CUT was evaluated as influenced by both system and product parameters, resulting in less than 50 s comparable to those obtained using capillary tubes. The newly developed MOC was validated for microbial destruction kinetic study under ohmic heating conditions using Clostridium sporogenes spores in buffer and concentrated maple sap. With its small volume, short CUT, and uniform temperature similar to capillary tubes in conventional heating, the MOC has the potential to be considered as a standard device for kinetic studies under ohmic heating.

A many-body quantum model is proposed as the mechanism responsible for accelerating rates of heat uptake by oceans as anthropogenic heat inputs rise

Abstract A recent many-body quantum approach to thermal radiation (1) reveals that the energy capacitance of heated water is about twice its heat capacitance, due to energy stored as local hybrid pairs of photons coupled resonantly to local matter excitations, with pair density weighted by mass density. Energy exchange between photons and localised dipole excitations inside water at steady temperature T, occurs at sites where a hybridisation potential within the Hamiltonian couples local oscillation modes to “free” photon modes. Photon modes in both directions are phase retarded at exit sides of a hybrid site. Optically sharp variations with frequency in the index of refraction n(f) and photon density of states follow. Exit spectral intensities at equilibrium temperature T carry quantum information on the energy density of matter excitations coupled to photons, while occupied hybrid sites are the source of all “free” photons and internal spectral intensities. The matter excitations coupled locally to photons are distinct from those that define specific heat, but in water both arise from molecular oscillations. The energy capacitance CEX(T) of hybrid pairs depends on mass density and is independent of heat capacitance CHT(T) which sets temperature T. CEX(T) is sensitive to T and doubles as a capacitance of energy and of “quantum information”. Expressions for CEX(T) are derived from first principles and applied to water. The density of occupied hybrids is amplified near surfaces by photons reflected off the surface, which create new hybrid pairs, but not extra heat. Energy capacitance CEX(T)+CHT(T) sets dT(t)/dt prior to a new equilibrium state emerging, after input heating rate dQ/dt is switched. Rising atmospheric intensities then raise T, dQ/dt, CEX(T) and CHT(T). The times available to cool overnight are fixed, so that a rising capacitance, adds to energy stored at an accelerating rate. 


Effect of the microwave treatment on anti-nutrients of soybeans

BACKGROUND: Soybeans contain anti-nutrients that have to be inactivated before being used as feed for livestock and poultry. AIM: Obtaining the new data on the effect of the heat treatment on soybeans. MATERIALS AND METHODS: Soybeans of the Dongsheng 22 and SK Alta varieties were processed with micronization, autoclaving and microwaves in the developed microwave unit. RESULTS: After micronization, the decrease in total starch was 10–16%, after autoclaving and microwave treatment — 15–17%. The three kinds of treatment did not have a significant effect on total phenolic content. The content of flavonoids increased by 7–9% after autoclaving and micronization and by 16% after microwave treatment. When micronizing and autoclaving soybeans, no changes in antioxidant activity were observed, but with microwave treatment, it increased by 3–5%. The decrease in trypsin inhibitor activity was 80% after microwave treatment and 73–79% after micronization and autoclaving. The tannin content was reduced by 10% with microwave treatment and by 7–9% after micronization and autoclaving. The decrease in phytic acid content was 43–45% and repeated for all kinds of treatment. CONCLUSION: The reduction of antinutrients after micronization, autoclaving and microwave processing ensures the use of soybeans for feed. Milder temperature conditions and cyclic processes of heating and cooling during microwave processing increase the safety of soybeans. The higher heating rate and low energy costs of microwave processing ensure economic feasibility.

Heat and mass flux dynamics of tangent hyperbolic nanofluid flow with unsteady rotatory stretching disk over Darcy-Forchheimer porous medium

Abstract The purpose of the research is to examine a tangent hyperbolic nanofluid flowing in three dimensions (3D) axisymmetrically on an unsteady rotatory stretching disk over a Darcy-Forchheimer porous medium. First order initial value problems (IVPs) are generated from the governing partial differential equations (PDEs) through the use of similarity transformation and linearization. The Runge-Kutta sixth order (RK6) is utilized to solve the IVP system using the shooting technique and the built-in Python program ‘fsolve model10’. Articles that have already been published are used to validate the implemented approach. Graphs are used to examine how various parameters affect velocity, temperature, and concentration. Additionally, the behavior of heat, mass flux, and skin friction in response to different parameters is investigated. The study’s findings showed that as the Forchheimer number and velocity slip parameter increased, the nanofluid’s radial and tangential velocities decreased as well. As temperature and concentration slip parameters increase, correspondingly, thicker and thinner boundary layer structures are seen. The drag force in the tangential and radial direction behaves in the same manner. Both the rates of heat and mass transfers are initiated for an increase Eckert and Prandtl numbers and demotivated for power-law index number. The dissipation effect with radiation and chemical reaction plays a major role in heat and mass fluxes, respectively. The study can be used in various computer storage, coatings, lubricants, and coolants.

Thermal decomposition of wheat straw pellets in a nitrogen environment: Characterization Using Thermogravimetric Analyzer

This experiment used a thermogravimetric (TG) analyzer within a nitrogen environment, investigating the thermal degradation patterns of wheat straw pellets (WSP) under temperatures ranging from 31 to 800°C and varying heating rates (5, 10, and 20 °C/min). Two pellet types were considered: T1 (100% wheat straw) and T2 (70% wheat straw, 10% sawdust, 10% bentonite clay, and 10% biochar). This study comprehensively analyzes WSP’s thermal degradation, emphasizing model selection, composition effects, heating rate, and temperature. Results highlighted higher volatile matter content and calorific value in WSP. Model-free methods were applied to analyze TG/DTG profiles, revealing three distinct zones in WSP thermal decomposition: drying, devolatilization, and carbonization. Devolatilization, especially its 1st and 2nd steps, was extensively examined, with a significant mass loss (approx. 65%) observed between 150 and 550°C. Higher heating rates induced a shift in thermogravimetric profiles to elevated temperatures. Maximum mass loss rates during devolatilization ranged from 4.41 to 16.28%/min for T1 and 4.0 to 15.9% for T2 pellets. Temperature significantly influenced mass loss and reaction rates, whereas heating rates had a negligible impact. Thermodynamic properties indicated equilibrium reactions during pyrolysis for both T1 and T2 pellets. Additionally, increasing heating rates correlated with an upward trend in the reactivity index. The findings contribute valuable knowledge for optimizing biomass utilization in combustion and pyrolysis processes.

Spectral reconstruction for radiation hydrodynamic simulations of galaxy evolution

Radiation from stars and active galactic nuclei (AGN) plays an important role in galaxy formation and evolution, and profoundly transforms the intergalactic, circumgalactic, and interstellar medium (IGM, CGM, and ISM). On-the-fly radiative transfer (RT) has started being incorporated in cosmological simulations, but the complex evolving radiation spectra are often crudely approximated with a small number of broad bands with piece-wise constant intensity and a fixed photo-ionisation cross-section. Such a treatment is unable to capture the changes to the spectrum as light is absorbed while it propagates through a medium with non-zero opacity. This can lead to large errors in photo-ionisation and heating rates. In this work we present a novel approach of discretising the radiation field at discrete photon energies, at the edges of the typically used photo-ionising bands, in order to capture the power-law slope of the radiation field. In combination with power-law approximations for the photo-ionisation cross-sections, this model allows us to self-consistently combine radiation from sources with different spectra and accurately follow the ionisation states of primordial and metal species through time. The method is implemented in GASOLINE2 in connection with TREVR2, a fast reverse ray tracing algorithm with 𝒪(Nactive log2 N) scaling. We compare our new piece-wise power-law reconstruction to the piece-wise constant method in calculating the primordial chemistry photo-ionisation and heating rates under an evolving UV background (UVB) and stellar spectrum, and find that our method reduces errors significantly, by up to two orders of magnitude in the case of HeII ionisation. We apply our new spectral reconstruction method in RT post-processing of a cosmological zoom-in simulation, MUGS2 g1536, including radiation from stars and a live UVB, and find a significant increase in total neutral hydrogen (HI) mass in the ISM and the CGM due to shielding of the UVB and a low escape fraction of the stellar radiation. This demonstrates the importance of RT and an accurate spectral approximation in simulating the CGM-galaxy ecosystem.

Optimizing pyrolysis and Co-Pyrolysis of plastic and biomass using Artificial Intelligence

The rapid increase in biomass and plastic waste poses significant environmental challenges. Co-pyrolysis of biomass with plastic wastes offers a promising avenue for sustainable waste management and renewable energy generation. This study covers several novel aspects: First, it investigates the impacts of feedstock composition and operating conditions in pyrolysis (individual feedstock) and co-pyrolysis (biomass and plastic wastes). The study reveals that synergistic effects, specifically improved yields and optimized temperature, exist in the co-pyrolysis of biomass and plastic wastes compared to individual feedstock. Secondly, a suitable blended machine learning predictive model (with Random Forest, Gradient Boosting Regressor, and XGBoost) and robust optimization framework are developed to address model accuracy, non-linear interactions, and uncertainties in pyrolysis such as temperature, heating rate, and biomass-to-plastic ratio. This study predicts the bio-oil yield quantitatively (amount) and qualitatively (composition) with high accuracy (R2 > 0.97). Thirdly, key factors contributing to yield include plastic content (18 %) and biomass type (13 %) have been identified through Gini feature importance and Shapley Additive Explanation (SHAP) analysis. Furthermore, multi-objective optimization techniques reveal the most optimal bio-oil yield under specific conditions, supported by uncertainty analysis, which confines bio-oil yield to a range of 30–50 %. Finally, it also demonstrates a case study to find the optimal bio-oil yield and quality conditions using co-pyrolysis of local resources, i.e., biomass (wood and bagasse) and plastic wastes. The case study suggests optimal conditions like > 50 °C heating rate, <50 min pyrolysis time, and > 60 % plastic content in a blend of wood and HDPE. This study assists industries and policymakers to assess and understand the viability of co-pyrolysis, optimal design parameters, and process impacts.

Impact of Dose and Heating Rate on Thermoluminescence Kinetics in Aquamarine (Be3Al2(SiO3)6:Fe)

Impact of Dose and Heating Rate on Thermoluminescence Kinetics in Aquamarine (Be3Al2(SiO3)6:Fe)

Undoped and Eu doped LaCa₄O(BO₃)₃ phosphors: Thermoluminescence characteristics with a focus on kinetic parameters, anomalous heating rate, and dose response

The thermoluminescence (TL) properties of LaCa₄O(BO₃)₃ (LACOB) phosphors, both undoped and doped with 0.5 % Eu³⁺, were synthesized using a microwave-assisted sol-gel method and analysed under beta irradiation doses ranging from 0.1 Gy to 700 Gy. The TL glow curves revealed prominent peaks at 100 °C and 285 °C for the Eu-doped sample. Activation energy values were calculated using the Hoogenstraaten and Booth-Bohun-Parfianovitch methods, yielding 1.52 eV and 1.48 eV for the undoped sample, and 2.07 eV and 2.01 eV for the Eu-doped sample, respectively. Eu³⁺ ions introduced deeper traps and enhanced the thermal stability of the material. Anomalous increases in TL intensity with rising heating rates were observed, deviating from typical thermal quenching behaviour; this phenomenon was explained using a semi-localized transition (SLT) model. The TL reusability measurements demonstrated a standard deviation of less than 5 %, indicating consistent and reliable performance across multiple cycles. The TL glow curve deconvolution identified six distinct peaks in the undoped sample, while the Eu-doped sample showed a more complex trap structure with eight peaks, indicating the introduction of additional or modified trapping sites by Eu doping. The figure of merit (FOM) values obtained from the deconvolution analysis were all below 2.5 %, indicating a good fit between the observed and fitted TL signals. These findings suggest that Eu³⁺-doped LACOB is a robust material for radiation dosimetry, with its enhanced sensitivity, stability, and versatility across various dosimetric applications.

Spectroscopic Study of Heating Distributions and Mechanisms Using Hinode/EIS

Heating distributions along coronal loops are obtained from spectroscopic data with the Hinode/EUV Imaging Spectrometer. The loop half-lengths L half are in the range of 24–107 Mm for our analysis of 18 loops. By using the analytical approximations to 1D hydrostatic numerical calculations of electron temperature T e (s) and density distributions n e (s) along a loop, the heating distribution that decreases with a heating scale height s H toward the loop top with a heating rate E 0 at the height of the transition region is estimated by applying a Bayesian analysis to the observed T e (s) and n e (s) derived by emission line ratios. We obtain s H = 10 ± 4 Mm increasing with L half, E 0 = 10−2.0±0.5 erg cm−3 s−1 decreasing with L half, and the heating flux F H = 107.0±0.4 erg cm−2 s−1. These loops show s H /L half = 0.21 ± 0.07, suggesting the concentration of the heating near the lower part. Compared to the previous study using imaging data, s H is comparable, while E 0 and F H are about an order of magnitude larger. We find that using the imaging data leads to the underestimation of the electron density and consequently the underestimation of E 0 and F H . We examine heating mechanisms using the power-law relation for F H , the field strength B base and L half: FH∝BbaseβLhalfλ . We find β=1.04−0.36+0.18 and λ=−0.99−0.05+0.04 , which show that the reconnection heating model is the most plausible.

Study on pyrolysis process and mechanism of organic coating of waste polyesterimide enameled wire based on density functional theory

The pyrolysis treatment of waste polyesterimide enameled wire offers significant advantages such as continuous processing, non-hazardous nature, and high resource recovery rate. However, research on its pyrolysis process and mechanism remains insufficiently explored. In this study, techniques including thermogravimetry (TG), Fourier transform infrared spectroscopy(FT-IR), pyrolysis–gas chromatography-mass spectrometry(Py-GC/MS) were employed to investigate pyrolysis temperature, weight loss rate, pyrolysis and kinetic parameters, composition and distribution of pyrolysis products, and changes in functional groups under different temperatures and heating rates. The pyrolysis of polyesterimide enameled wire can be divided into three stages: volatilization of specific components (314.8 °C,1.6 %), rapid decomposition of polyesterimide (435.2 °C, 44.7 %), and generation of small organic molecules with the fixation of pyrolytic carbon (750 °C, 9.0 %). The main components of the pyrolysis gas products include aromatic compounds, ethers, aromatics, ketones, and carbon dioxide. At 400 °C, a substantial amount of pyrolysis gas products and free radicals are produced, with an increase in aromatic hydrocarbons. The carbon distribution in the pyrolysis products mainly focuses on C6-C10 and C11-C15, and many organic compounds such as benzoic acid, phenol, and aniline are generated. Based on density functional theory, the bond dissociation energies in the polyesterimide were calculated. This clarified the possible thermal decomposition pathways of the polyesterimide and provided the energy barrier values, elucidating the generation mechanism of pyrolysis products during thermal decomposition. The copper atom in specific location reduces the negative ESP of O and increases the positive ESP of H in EPI, which makes H more likely to attach to O. The presence of Cu increases the ESP range and promote the pyrolysis process. This study provides a theoretical basis for the high-value recycling of waste polyesterimide enamelled wire.

Effect of PTFE content on the laser-induced ignition and combustion characteristics of Al@PTFE composite fuels

This paper prepared aluminum@polytetrafluoroethylene (Al@PTFE) composite fuels with different PTFE contents and evaluated the effect of PTFE content on the thermal and combustion characteristics via multiple characterization methods. The scanning electron microscopy (SEM) and thermogravimetry–differential scanning calorimetry (TG-DSC) results showed that the PTFE was well coated on the surface, and the higher the PTFE content, the faster the oxidation reaction rate. Al@PTFE_8% fuel demonstrated more stable thermal performance and higher weight gain. Al@PTFE_15% had a weak endothermic peak at 337.2 °C, while the other two fuels did not appear. The nanosecond pulsed laser-induced plasma ignition (LIPI) test showed that compared to pure Al counterpart, Al@PTFE fuels could effectively shorten the ignition delay and promote the energy release, for Al@PTFE_8% with a reduction of 41.9% in ignition delay and an increase by 17.1 % in combustion temperature. The self-sustaining burn time decreased as the PTFE content increased. The gas-phase combustion of Al@PTFE fuels were more pronounced, and their AlO spectral signal intensity were stronger. The Al@PTFE combustion residues showed lots of cracks and holes, and the mass fraction of O was increased from 22.96 % (Al) to 30.53 % (Al@PTFE_8%). The proposed combustion mechanism reveals that PTFE destroyed the alumina film that hindered combustion, significantly promoting the combustion of Al particles. This study provides guidance for laser-induced plasma ignition of this material under ultrahigh heating rates.

Modeling the Energy-dependent Broadband Variability in the Black Hole Transient GX 339–4 Using AstroSat and NICER

We present a spectro-timing analysis of the black hole X-ray transient GX 339–4 using simultaneous observations from AstroSat and the Neutron Star Interior Composition Explorer (NICER) during the 2021 outburst period. The combined spectrum obtained from NICER, Large Area X-ray Proportional Counter and SXT data is effectively described by a model comprising a thermal disk component, hard Comptonization component, and reflection component with an edge. Our analysis of the AstroSat and NICER spectra indicates the source to be in a low/hard state, with a photon index of ∼1.64. The power density spectra obtained from both AstroSat and NICER observations exhibit two prominent broad features at 0.22 Hz and 2.94 Hz. We generated energy-dependent time lag and fractional root mean square (frms) at both frequencies in a broad energy range of 0.5–30 keV and found the presence of hard lags along with a decrease in variability at higher energy levels. Additionally, we discovered that the correlated variations in accretion rate, inner disk radius, coronal heating rate, and the scattering fraction, along with a delay between them, can explain the observed frms and lag spectra for both features.

Combustion phases of magnesium alloys based on predicted heating rate using machine learning

Combustion phases of magnesium alloys based on predicted heating rate using machine learning

A Simple Model for the Emergence of Relaxation‐Oscillator Convection

AbstractEarth's tropics are characterized by quasi‐steady precipitation with small oscillations about a mean value, which has led to the hypothesis that moist convection is in a state of quasi‐equilibrium (QE). In contrast, very warm simulations of Earth's tropical convection are characterized by relaxation‐oscillator‐like (RO) precipitation, with short‐lived convective storms and torrential rainfall forming and dissipating at regular intervals with little to no precipitation in between. We develop a model of moist convection by combining a zero‐buoyancy model of bulk‐plume convection with a QE heat engine model, and we use it to show that QE is violated at high surface temperatures. We hypothesize that the RO state emerges when the equilibrium condition of the convective heat engine is violated, that is, when the heating rate times a thermodynamic efficiency exceeds the rate at which work can be performed. We test our hypothesis against one‐ and three‐dimensional numerical simulations and find that it accurately predicts the onset of RO convection. The proposed mechanism for RO emergence from QE breakdown is agnostic of the condensable, and can be applied to any planetary atmosphere undergoing moist convection. To date, RO states have only been demonstrated in three‐dimensional convection‐resolving simulations, which has made it seem that the physics of the RO state requires simulations that can explicitly resolve the three‐dimensional interaction of cloudy plumes and their environment. We demonstrate that RO states also exist in single‐column simulations of radiative‐convective equilibrium with parameterized convection, albeit in a different surface temperature range and with much longer storm‐free intervals.

Direct Ink Writing and Rapid Microwave Sintering of Alumina

The additive manufacturing of ceramics is gaining attention due to difficulties in fabricating complex ceramic parts because of its hard and brittle nature. Direct ink writing (DIW) is a unique process in which solid-loaded slurry is extruded to print complex-shaped ceramic parts directly. In the present work, a new composition of high-solid loaded (76 wt.%) alumina ink is prepared for printing ceramic parts with complex structures. The rheology of ink is optimized to ensure the shear thinning behavior of the ink, while thermogravimetric analysis (TGA) of the printed part was carried out to optimize the debinding temperature. The printed alumina part is sintered using the conventional furnace and rapid microwave sintering process, and a comparison has been made. Microwave, a rapid sintering method with a high heating rate, produced >97% dense specimen, while the hardness and flexural strength values of 15.18 ± 0.6 GPa and 148.87 ± 2.14 MPa were achieved, respectively. Rapid microwave sintering of additively manufactured ceramic parts can reduce the energy consumption and overall production time needed to manufacture ceramic parts.

Non-isothermal kinetic analysis of phase transformations in Fe-Co-V-Mo semi-hard magnetic alloy

In this study, the non-isothermal kinetics and phase transformations within the Fe-Co-V-Mo alloy were investigated. Four distinct transformations were identified: disorder → order (T1), first-stage polymorphic (T2), order → disorder (T3), and second-stage polymorphic (T4). The activation energy (E) for each transformation was determined using isoconversional methods. Fitting model were employed to calculate the kinetic triplets, confirming that all transformations follow the Avrami model. The Johnson-Mehl-Avrami (JMA) and Šesták-Berggren (SB) models were used to determine other kinetic parameters (n, M, and N). The findings suggest that the growth mechanisms for transformations T3 and T4 are interface-controlled, whereas transformation T2 is diffusion-controlled. Consequently, the A3/2 and A3 mechanisms were identified as predominant mechanisms for transformations T2 and T4, respectively. Additionally, transformation T3 follows the A3 mechanism at heating rates of 10 and 20 K/min, and the A2 mechanism at 30 K/min. Kinetic analysis revealed that the addition of Mo in Fe-Co-V alloys, acting as a ferrite (α) stabilizer, decreases the onset temperatures of transformations T1 and T3. Conversely, it increases those of transformations T2 and T4. Furthermore, Mo influences the reduction of E associated with transformation T3.

Thermal and Dielectric Properties of EuF3: Gd @ Tryptophan

Abstract EuF3: Gd @ tryptophan was synthesized via aqueous solution route at room temperature. The XRD studies shows hexagonal phase of synthesized nanoparticles with lattice parameters a = b = 6.966 (A°), c = 7.322 (A°). The lattice parameter values are in good agreement with (JCPDS card no 32-0373). The particle size of nanoparticles was calculated using Debye-Scherer formula and it is found to be 73.54 nm. Nanoparticles has flake like morphology having size of the order of 56 nm – 71 nm with nanoparticles has average size of 13 nm. The TEM image shows globular aggregates with assorted size were also seen with diameter 56 nm – 71 nm from which the flower like star structures originates. The TGA/DTA analyses of synthesized sample were studied up to 1500°C at heating rate of 0.01°C – 100°C/min. The variation in dielectric constant ε′, dielectric loss ε″ and tangent loss (tan δ) with frequency (100 Hz – 5 MHz) was studied at room temperature. The dielectric constant and dielectric loss are found to decrease exponentially with frequency. The low value of dielectric loss at higher frequencies indicates its use in electronic industry.

Ultrasound-assisted Adsorptive Desulfurization of Dibenzothiophene from Model Fuel on K2CO3-Activated Biochar

A novel mesoporous activated biochar (ABC) was developed from an equal mix of date and olive stones and implemented in the ultrasound-assisted adsorptive desulfurization (USADS) of model gasoline (300 ppm DBT/n-hexane) and model kerosene (300 ppm DBT/cyclohexane). The biowaste blend was carbonized at 450°C for 75 min at a 10°C/min heating rate, followed by K2CO3-activation. The superior ABC was synthesized at 750°C for 1h using an impregnation ratio of 1:1 K2CO3: biochar. The BET surface area and average pore diameter of the resulting ABC were 1099.70 m2/g and 5.14 nm, respectively. The USADS of both models was achieved at relatively mild experimental conditions (0.20 g of the ABC 30°C, 40 min, and 120 W US power). At these conditions, the USADS of model gasoline amounted to 97.32 % compared to 99.39 % for model kerosene. The USADS process of both models followed the Langmuir model of the adsorption isotherms and the pseudo-2nd-order kinetics model. The ABC was recoverable and effective until the 5th regeneration cycle and reused reasonably. The maximum USADS of real gasoline (88.12 %) was achieved using 1.0 g of the ABC at 30°C for 120 min.