Theory Of Adsorption Research Articles

Mathematical Expression and Prediction of VOCs Adsorption Capacity and Isotherm.

Adsorption capacity prediction, which needs to be based on the precise structure-capacity relationship, is important for better adsorbent design. However, the precise adsorption contribution coefficients of pores of different sizes for volatile organic compound (VOC) adsorption remain unclear. Herein, a control variable method is employed as a generative model to realize the numerization of the precise structure-capacity relationship. For the first time, a concise equation is proposed that can predict the adsorption capacities/isotherms of unknown adsorbents through their pore structure parameters. Interestingly, practical VOC adsorption amounts aligned with predicted values obtained by simultaneously considering pore volume (which undergoes volume-filling adsorption) and surface area (which undergoes surface-covering adsorption) as input variables. Derivation of the equation is based on classical adsorption theories and mathematical expression of the precise structure-capacity relationship obtained from actual experimental results. Each parameter in the equation has a specific physical meaning. This unprecedented VOC adsorption capacity/isotherm prediction method provides in-depth insight for accurate quantification of VOC adsorption, with great potential for gas adsorption prediction and guidance in the development of adsorption materials and technologies.

Cooperative lattice theory for CO2 adsorption in diamine-appended metal-organic framework at humid direct air capture conditions.

The effect of humidity on the cooperative adsorption of CO2 from the air on amine-appended metal-organic frameworks is studied both experimentally and theoretically. Breakthrough experiments show that, at low relative humidities, there is an anomalous induction effect, where the kinetics at short times are slower than kinetics at long times. The induction effect gradually vanishes as relative humidity is increased, corresponding to an increase in CO2 adsorption rate. A new theory is proposed based on the lattice kinetic theory (LKT), which explains these experimental results. LKT can accurately represent the measured data over the full range of humidities by postulating that the presence of adsorbed water shifts the equilibrium clusters from cooperatively bound chains to non-cooperatively bound CO2. A consequence of this transition is that CO2 exhibits step adsorption isotherm in dry air and a standard Langmuir adsorption isotherm in high humidity air.

Research on the microscopic mechanism and model applicability differences of CH4 and CO2 adsorption based on molecular dynamics

To verify the accuracy and rationality of the molecular simulation model, the microscopic mechanism of gas adsorption was analyzed and clarified from a microscopic perspective. The effect of molecular models created by direct construction and supercell expansion on the adsorption capacities of CH4 and CO2 has been analyzed. Eight coal-based molecular configurations were created to simulate the isothermal adsorption process of CH4 and CO2 using various coal-based molecular configurations. Using physical experiments, the validity of different construction methods for coal-based molecular structures was verified. The direct construction method was chosen to simulate the effect of various coal-based molecular numbers on the adsorption capacity of CH4 and CO2. The results show that the adsorption capacity of CO2 on coal is greater than that of CH4. The isothermal adsorption curves of CH4 and CO2 in coal-based molecular systems constructed using different methods reveal that the adsorption of methane on coal molecules adheres to the Langmuir monolayer adsorption theory. The adsorption sites for methane increase with the rise in free volume. The structure directly constructed and the supercell expansion directly determines the amount of methane adsorbed by each coal based molecule. The adsorption constants of CH4 and CO2 on the supercell extended structure are more volatile than those on the directly constructed structure, and the structure constructed directly for different coal based molecules is better than the supercell extended structure. The simulation using the direct construction method shows that as the number of coal-based molecules in the molecular configuration increases, The isothermal adsorption quantities of CH4 and CO2 increase linearly. The molecular configuration is not affected by the number of anthracite molecules. Molecular configuration is not affected by the number of anthracite molecules. The rationality of model construction has no obvious relationship with the number of coal based molecules.

Investigation of the impact of micro-nano pore geometry on CH4 adsorption

CH4 is a clean fossil fuel that is widely used in the gas supply of homes and industry, and its energy value is increasingly important. Coal pores provide certain conditions for the storage of CH4. In order to reveal the microscopic adsorption mechanism of CH4 in different pores under high pressure, based on the experimental results, a cross-shaped pore model was proposed, and then molecular simulation was used to construct three kinds of cross-shaped, round and slit pore models for simulation experiment verification. The changes of adsorption parameters, such as adsorption amount, adsorption heat, adsorption energy, adsorption potential and adsorption entropy, were analyzed during the adsorption process. Combined with adsorption and condensation theory, the influence of different geometric pores on the adsorption of CH4 was further verified. The results show that round pore have more adsorption sites, larger adsorption quantity and stronger adsorption capacity, followed by cross pore, while slit pore have the weakest adsorption capacity and least adsorption sites. Under high pressure susaturated adsorption, the interaction force between molecules is stronger, the affinity is higher, the molecules are arranged in order, and the adsorption system is more stable, and the adsorption capacity of slit pore > cross pore > round pore is displayed. This study further verifies the mechanism of the effect of pore geometry on CH4 adsorption, which provides a strong support and theoretical basis for CBM mining engineering.

Supercritical Methane Adsorption Characteristics and Pore Structure Characteristics of Deep Middle Rank Coal

Abstract In order to accurately analyze the adsorption characteristics, pore structure, and fractal law of deep middle rank coal, high-pressure isothermal adsorption tests based on magnetic levitation high-pressure thermobalance and pore structure tests based on mercury intrusion method were carried out on coal samples collected from typical kilometer level deep wells. The fractal law of sponge model was studied. The results showed that: a. The weight method adsorption test showed “excess adsorption” phenomenon with the increase of equilibrium pressure, and the modified Gibbs surface excess adsorption theory was in line with the Langmuir adsorption model; b. The distribution of macropore volume in deep middle rank coal accounts for a dominant proportion of 57.44% to 62.47%, and the proportion of microporous specific surface area reaches 72.96% to 74.27%, indicating that microporous adsorption capacity is the strongest; c. The pore structure parameters and adsorption constants exhibit strong nonlinear characteristics.

Influence of Supercritical Conditions on Isothermal Adsorption Capacity Calculation of Methane and Model Optimization.

The study of isothermal adsorption models for coal and methane under supercritical conditions helps us to understand the gas content distribution in coal seams and improve gas management in coal mines. Coal samples from the Hebi mine and Longshan coal mine were selected for this research. Using the weight method, isothermal adsorption curves of supercritical methane at temperatures of 308, 313, and 318 K were measured. The adsorption phase density of supercritical methane was obtained by using the intercept method and model fitting, and the absolute adsorption capacity of methane was calculated. Simultaneously, the pore volume and specific surface area of the coal samples were tested, and the isothermal adsorption model for supercritical methane was studied and optimized. The results indicate that using mercury intrusion, low-temperature N2, and low-temperature CO2 adsorption methods for testing coal sample pore structures allows for multiscale characterization of the coal pore structure. Based on the Gibbs excess adsorption theory, the phase density of methane obtained from the intercept method and model fitting effectively represent the isothermal adsorption curve of supercritical methane. By combination of the specific surface area and pore volume distribution of the coal with the absolute adsorption capacity of methane, the number of methane adsorption layers on the coal surface was calculated to be between 1.11 and 1.3 layers. This suggests that the isothermal adsorption model for supercritical methane on coal is not solely micropore filling or single molecular layer adsorption but primarily single molecular layer adsorption with concurrent micropore filling adsorption. Based on this adsorption mechanism, an L-DA isothermal adsorption model for supercritical methane on coal was established. The L-DA isothermal model shows good fitting results and effectively explains the adsorption characteristics of supercritical methane on coal.

Kinetics and catalysis: Direct mechanisms, autonomous reaction pathways, and the constitutive rate function

AbstractRate functions of catalytic reactions are derived from direct mechanisms based on an adsorption theory and a kinetic mathematical model. Often, more than one direct mechanism corresponds to an overall chemical reaction. Since each direct mechanism can potentially produce a distinct rate function, it is likely that more than one independent rate function describes the rate of an overall reaction. This appears to be a fundamental property of the structure of the kinetics of heterogeneous catalysis and this article addresses this possibility via an examination of the independent direct mechanisms of the steam methane reforming and ammonia synthesis.

D-BJH: The Intrinsic Model for Characterizing the Pore Size Distribution of Porous Materials.

A novel approach, the differential Barrett-Joyner-Halenda model (D-BJH), is proposed to address the limitations of the traditional BJH model in determining the pore size distribution (PSD). This method integrates multilayer adsorption and capillary condensation processes using advanced numerical techniques, notably, a Galerkin-based framework for solving the differential BJH equations. The D-BJH model offers a precise analytical framework, establishing itself as a benchmark in adsorption theory. It enables accurate PSD calculations and provides robust theoretical support for interpreting adsorption isotherms. Additionally, a simplified D-BJH method allows for direct point-by-point PSD calculation, reducing computational complexity and eliminating cumulative errors inherent in traditional methods like BJH, DH, CI, and VBS. The D-BJH model demonstrates that PSD is directly related to the differential function of the isotherm and pore size concerning relative pressure. Comparative analyses with BJH, DH, and NLDFT models show that D-BJH effectively explains fundamental adsorption mechanisms, such as the "spurious peak" observed in desorption branches. This work expands the applicability of the BJH model, proving that both the D-BJH model and its simplified method are accurate and comprehensive for characterizing the pore structures of microporous and mesoporous materials.

Chitosan grafted with gallic acid and cerium dioxide hybrid nanocomposites as environmentally friendly corrosion inhibitors for mild steel: An experimental and computational study

Chitosan grafted with gallic acid (CS-GA), along with CS-GA doped with CeO2 nanoparticles (CS-GA-CeO2) were synthesized as novel environmentally friendly mild steel corrosion inhibitors. The formation of these derivatives was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), hydrogen nuclear magnetic resonance spectroscopy (1H NMR), and thermal analysis (TGA). Based on potentiodynamic polarization curves (PDP) measurements, the inhibitors acted primarily as hybrid inhibitors, while following the Langmuir adsorption theory model. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy(XPS) and 3D surface profiles, confirmed that CS-GA-CeO2 adsorbed on the mild steel forming a protective layer thus preventing the invasion of corrosive media. The corrosion protection mechanism of chitosan derivatives was investigated by molecular dynamics simulations. Electrochemical measurements were used to investigate the corrosion inhibition by CS-GA and CS-GA-CeO2 on mild steel in a 3.5 % NaCl solution. At room temperature, the highest inhibition efficiency (93.58 %) was achieved at 200 ppm CS-GA-CeO2. Modified chitosan nanocomposites were confirmed as promising corrosion inhibitors.

Semiconductive Tendency of the Passive Film Formed on Super Austenitic Stainless Steel SR-50A in Acidic or Alkaline Chloride Solutions

Stainless steel is widely used in various industrial fields due to its excellent corrosion resistance and mechanical properties. The key to this corrosion resistance is the thin passive film that naturally forms on the metal surface. Passive films are characterized by oxide film theory and adsorption theory, each uniquely explaining the structure and mechanism of the protective film on the metal surface. Research on the semiconductive properties of passive films on stainless steel offers diverse viewpoints, classifying theories into the point defect model and the bipolar fixed charge-induced passivity. Specific changes in passive film attributes that lead to degradation, however, are not fully understood. In this study, we analyzed the inner and outer layers of the passive film on super austenitic stainless steel SR-50A under various conditions in acidic and alkaline chloride environments. The interpretations of these results were based on the point defect model and the bipolar model for the passivation mechanism, and correlations between p-type and n-type semiconductor properties and passivation behavior were examined. The surface of the stainless steel forms a passive film comprising two layers with p-type and n-type semiconductive properties, independent of the pH of the solutions. The corrosion resistance increases as the p-type and n-type semiconductive tendencies become more balanced, consequently enhancing the properties of the passive film.

Controllable synthesis of porous boron nitride fibers modified by cobalt and nickel oxides for efficient ceftriaxone sodium adsorption from aqueous solution.

Antibiotics can easily enter the water environment through direct or indirect approach, causing environmental pollution and endangering the health of organisms. Therefore, development of highly efficient adsorbent materials to adsorb and remove antibiotics is necessary. Here, cobalt oxide and nickel oxide are uniformly and tightly bonded on the surface of porous boron nitride fibers (PBNFs-NiCo), significantly increasing the number of functional groups (B-O and N-H) and hydrogen bond receptors within PBNFs. The total pore volume and specific surface area of resulting PBNFs-NiCo can reach up to 0.48 cm3/g and 720.3 m2/g, respectively. Encouraged by the unique micromorphology and chemical composition mentioned above, PBNFs-NiCo exhibits excellent ceftriaxone sodium (CS) adsorption ability, showing the adsorption capacity and removal efficiency up to 410.9 mg/g and 96.5%, respectively. Chemical adsorption plays an important role in their adsorption behavior, abiding by Langmuir adsorption theory and pseudo-second-order kinetic equation. Importantly, PBNFs-NiCo exhibits fascinating adsorption effects in surroundings with pH ranging from 4 to 6, 25 °C and varying salt concentrations. This work would establish a practical and feasible foundation for the practical application of PBNFs-NiCo for CS adsorption in aqueous solution.

Adsorption of Pb(II) from aqueous environment on artificially synthesized mordenite and its biochar composite

Biochar was used to enrobe artificially synthesized mordenite by co-pyrolysis, and the performance of the composite in removing lead from dilute solutions was compared with that of the mordenite alone. The optimal parameters for the hydrothermal synthesis of mordenite were as follows: crystallization temperature of 180℃, crystallization time of 4 days, pH value of 11, and aging time of 24 h. The optimal mass ratio of mordenite to biochar was 20:1, and the pyrolysis temperature was 500℃. Adsorption equilibrium was reached within 3 h, yielding a total average lead removal of 78.9 % for mordenite alone and 98.6 % for the composite. Pseudo-second-order kinetics and Langmuir isotherms adequately described the data. The predicted maximum adsorption capacities were 156.6 mg/g for the mordenite alone and 283.4 mg/g for the composite. When the initial concentration of Pb(Ⅱ) was 80 mg/L, the optimum doses were determined to be 6–7 g/L for the mordenite and 5–6 g/L for the composite. At pH less than 7, mordenite removed up to 80 % of the lead and the composite removed between 90 % and 100 %. Coexisting ions had little effect on mordenite, but K(I), Ca(II), and Mg(II) could significantly increase the adsorption efficiency by up to 5.7 % for the composite. Furthermore, tannic acid and fulvic acid showed a promoting effect. Adsorption mechanisms were proposed based on the characterization results of the materials before and after adsorption, batch experiments, and density functional theory calculations. Specifically, mordenite adsorption was found to be based primarily on electrostatic attraction, surface complexation and ion exchange. Adsorption by the composite also involved π-electronic interaction and coprecipitation. In general, the composite exhibited better adsorption performance than mordenite alone.

CO2 Adsorption by CMK-3 at Low Temperatures and High Pressure to Reduce the Greenhouse Effect.

In this study, the maximum CO2 capture capacity of an ordered mesoporous carbon (CMK-3) was evaluated at high pressure (35 atm) and several temperatures (0, 10, 20, and 35 °C). CMK-3 was synthesized with the hard template method (silica SBA-15) using furfuryl alcohol and toluene as carbon sources. The CO2 adsorption isotherms were fitted to the following adsorption theories: Freundlich, Langmuir, Sips, Toth, Dubinin-Radushkevich, and Temkin. The maximum capture capacity (726.7 mg·g-1) was achieved at 0 °C and 34 atm. The results of the study of successive adsorption-desorption cycles showed that multi-cycle reversible gas capture processes could be used in optimal temperature and pressure conditions. It was determined that 0.478 g of CMK-3 would be required to reduce the CO2 concentration in 1 m3 of air to pre-industrial levels (280 ppm). The obtained results may contribute to technological developments for the mitigation of human impacts on the environment through the capture of atmospheric CO2.

Rational utilization of the size and electronic effect of inhibitors enabling high polishing rate with minimum corrosion in copper chemical mechanical polishing

Chemical mechanical polishing (CMP) relies on corrosion to remove excess materials, while also on corrosion inhibitors to ensure post-polished surface quality. The robust adsorption of inhibitors onto metal surfaces typically improves inhibition effectiveness but significantly reduces the polishing rate. In this study, we propose and validate a novel strategy that focuses on the utilization of large-sized physisorption-type inhibitors to address this inherent conflict. By incorporating disproportionated rosin (DR) as the inhibitor, the developed slurry facilely obtained a balance between polishing efficiency and quality for copper CMP. The inhibition mechanism of DR was elucidated through electrochemical characterization, adsorption isotherms, and reactive forcefield molecular dynamics (ReaxFF MD) simulations. The weak physisorption of the inhibitors facilitated their easy removal, resulting in minimal impact on the polishing rate. Additionally, the large-size structure of DR effectively hindered corrosive substances from reaching concave areas not under external force, thereby demonstrating superior inhibition efficacy. The adsorption mode of DR on copper was simultaneously determined through adsorption isotherms and ReaxFF MD simulations, marking the first instance of linking classic adsorption theory with MD simulations. The advantage of the ReaxFF MD simulations over classic MD simulations and density-functional-theory calculations for the metal-inhibitor adsorption systems was also discussed and demonstrated.

Polydopamine coating for enhanced electrostatic adsorption of methylene blue by multiwalled carbon nanotubes in alkaline environments

The removal of dye molecules in alkaline environments is an issue that should receive increased attention. In this study, the interaction mechanism between polydopamine-modified multiwalled carbon nanotubes (P-MWCNTs) and multiwalled carbon nanotubes (MWCNTs) with the cationic dye methylene blue (MB) in alkaline environments was explained in depth by adsorption, spectroscopy, and density functional theory (DFT). The mechanism of action and dominant forces between the adsorbent and adsorbate were analyzed graphically by introducing energy decomposition analysis (EDA) and an independent gradient model (IGM) into the DFT calculations. In addition, the force distribution was investigated through an isosurface. Moreover, batch adsorption studies were conducted to evaluate the performance of MWCNTs and P-MWCNTs for MB removal in alkaline environments. The maximum MB adsorption capacities of the MWCNTs and P-MWCNTs in solution were 113.3 mg‧g−1 and 230.4 mg‧g−1, respectively, at pH 9. The IGM and EDA showed that the better adsorption capacity of the P-MWCNTs originated from the enhancement of the electrostatic effect by the proton dissociation of polydopamine. Moreover, the adsorption of MB by MWCNTs and P-MWCNTs in alkaline environments was governed by dispersion and electrostatic effects, respectively. Through this study, it is hoped that progress will be made in the use of DFT to explore the mechanism of adsorbent-adsorbate interactions.

Green synthesis of copper nanoparticles using white tea leaf extract: Characterization, adsorption behavior, and antibacterial applications

Biosynthesis of metal nanoparticles is a cost-effective and environmentally friendly technology. In the present study, copper nanoparticles (CuNPs) were synthesized using white tea leaf extracts. They were then characterized for their chemical structure and evaluated ability for the methylene blue (MB) degradation in the adsorption system with H2O2. XRD and FTIR analyses revealed that the CuNPs were present as an amorphous phase, with the O-H polyphenol compound bound to the Cu ion. The XPS deconvolution indicated the presence of Cu2+ and Cu+ in the CuNPs. TEM images revealed that the average particle size was less than 10 nm. The CuNPs synthesized using different precursors exhibited effective ability for the MB degradation in the adsorption system. Based on the adsorption theory, the pseudo-second-order model fitted well with the experimental data, and the thermodynamic calculation suggested that the reaction was endothermic, and spontaneous. The CuNPs synthesized using the CuSO4 precursor exhibited higher antibacterial activity compared to those synthesized using Cu(NO3)2. In conclusion, white tea leaf extract is an inexpensive and easily available precursor for the biosynthesis of copper nanoparticles. Further analysis based on an assumed degradation work will be considered in future work.

Analysis of the influence of temperature on the adsorption characteristics of coal: Insights into low-temperature outburst prevention

To investigate the impact of temperature reduction on the adsorption characteristics of coal gas, isothermal adsorption experiments were conducted with environmental temperature and moisture content as variables. The changing patterns of coal gas adsorption characteristics, adsorption theories, and the temperature response of gas expansion were analyzed. Furthermore, engineering measures for preventing gas outbursts in low-temperature frozen coal seams were discussed. The research findings indicate that the gas adsorption capacity of coal samples increases with decreasing temperature. When the temperature decreases from 20 to −20 °C, the gas adsorption capacity decreases from 34.48 to 19.90 cm3/g. At the same pressure, the adsorption capacity of coal is negatively correlated with temperature. The Langmuir theoretical model better reflects the adsorption law of coal gas under different environmental temperature conditions, wherein the adsorption constant “a” gradually decreases with the increase in environmental temperature. In a closed space, the gas pressure decreases with the decrease in coal sample temperature. Under the new adsorption equilibrium, the gas pressure in the coal sample tank decreases linearly with temperature. Coal samples with different moisture contents exhibit varying degrees of decrease in gas pressure at the same temperature, with higher moisture content resulting in a smaller decrease in gas pressure. Gas expansion energy decreases linearly with the decrease in coal temperature, indicating a proportional relationship between gas expansion energy and coal gas release pressure. As the temperature decreases, the gas pressure decreases. Based on the experimental results, a synergistic approach for preventing gas outbursts through low-temperature freezing is proposed.

New insight into CH4 adsorption mechanism in coal based on modeling analysis of different adsorption theories

Based on the principle of Gibbs excess adsorption measurement, high-pressure isothermal adsorption and desorption experiments of CH4 were performed on fractured coal samples, and CH4 adsorption phase density was obtained by the intercept method according to the experimental data. The Langmuir model, BET model, DA model, and their corrected model, the supercritical adsorption models were used for the fitting analysis of CH4 excess adsorption capacity. A hybrid model of different adsorption theories was developed based on CH4 adsorption phase density and theoretical adsorption capacity predicted by the intercept method. The transition in the occurrence pattern and control mechanism of CH4 in coal were investigated. The fitting of the Langmuir model, BET model, DA model, and their corrected models, the SBET model, the SDA model, and the SDA-L model to the CH4 excess adsorption capacity in coal shows that all multilayer adsorption theory model is not suitable for fitting the CH4 excess adsorption capacity in coal. The uncorrected Langmuir model and DA model are only suitable for fitting the CH4 excess adsorption capacity in coal in the low-pressure stage (pressure below 10 MPa). The corrected Langmuir model, the corrected DA model, the SDA model, and the SDA-L model can be used to fit the CH4 excess adsorption capacity in coal, but they show some bias in predicting the theoretical CH4 adsorption capacity and the CH4 adsorption phase density. The fitting of the three main adsorption theory models suggests that there may be simultaneous monolayer adsorption and microporous filling adsorption. The fitting results of the hybrid model based on monolayer adsorption and microporous filling adsorption theory depend on showing that with the increase of temperature, the occurrence of CH4 in coal gradually changes from mainly monolayer adsorption to mainly microporous filling adsorption, and the transformation of occurrence mode is related to temperature and the development of pores in coal.

Gas Sorption Characterization of Porous Materials Employing a Statistical Theory for Bethe Lattices.

In the present work, a recently developed statistical theory for adsorption and desorption processes in mesoporous solids, modeled by random Bethe lattices, has been applied to obtain pore size distributions and interpore connectivity from sorption isotherms in real random porous materials, employing a robust and validated methodology. Using the experimental adsorption-desorption N2 isotherms at 77.4 K on Vycor glass, a porous material with random pore structure, we demonstrate the solution of the inverse problem resulting in extracted pore size distribution and interpore connectivity, notably different from the predictions of earlier theories. The results presented are corroborated by the analysis of 3D digital images of reconstructed Vycor porous glass, showing excellent agreement between the predictions of geometric analysis and the new statistical theory.

Quantifying pore structure heterogeneity of shale samples after solvent extraction following anhydrous and hydrous pyrolysis

Heterogeneity is an important pore structure characteristic of shale formations that can impact reservoir transport properties. To better understand the heterogeneity intrinsic to the shale pore structure, gas adsorption and multifractal theory were combined to analyze data from artificially matured shale samples under both anhydrous and hydrous pyrolysis conditions. We compared two sets of samples: one that was kept intact (not treated with organic solvent), and the other set that was treated with an organic solvent to remove any liquid petroleum that was produced during the pyrolysis process. The results revealed differences in the pore structure parameters of the aliquots under these two pyrolysis conditions as well as treated vs. intact. Furthermore, at the same pyrolysis temperature, the disparity in surface area and pore volume before and after extraction of petroleum was found to be greater with anhydrous compared to hydrous pyrolysis conditions. Regardless of the pyrolysis conditions, when the pyrolysis temperature is under 400 °C, pore structural heterogeneity following extraction of petroleum is often small compared to the situation when yield is still present in the pores. As a result, the movable oil under both maturity routes can increase pore structure heterogeneity. Considering the results, when analyzing shale adsorption data for pore structure heterogeneity, experimental design would have an impact on the final outcome and data interpretation. This is the first study that investigates the effect of the movable oil and solvent extraction process on pore structure heterogeneity in relation to the thermal evolution of shale in the presence and absence of water.