Elimination Of Volatile Organic Compounds Research Articles

Mechanistic effects of graphitization and oxygen functional groups on benzene competitive adsorption of porous carbon under high humidity conditions

Porous carbon is an ideal adsorbent for the elimination of volatile organic compounds (VOCs) attributed to their price, availability and excellent adsorption capacity. However, there are significant variation in the adsorption capacity and adsorption selectivity of different precursors for VOCs under humid conditions after modification because of the differences in their own structural properties. In this study, graphitized hydrophobic porous carbon with excellent specific surface area was successfully synthesized by selecting bamboo fiber, maize, coconut husk and coal as precursors and potassium hydroxide as an activator. Among them, the dynamic adsorption capacity of benzene in the sample with bamboo fiber as precursor was maintained at 74.7% under the high humidity condition (RH90%) compared with the dry state (RH0%). Grand Canonical Monte Carlo (GCMC) simulations and weak interaction force analyses showed that enhanced dispersion attraction between graphitized carbon surfaces and benzene molecules in comparison to disordered carbon surfaces. The existence of oxygen functional groups enhanced the interaction between porous carbon and water through hydrogen bonding leading to preferential adsorption of water molecules, which resulting in the decrease of their adsorption performance in wet condition. This research provided theoretical and experimental views of the effects of graphitization and oxygen functional groups on the competitive adsorption capture of benzene and water by porous carbon, which further provided a reliable approach to synthesizing porous carbon with high adsorption capture for benzene removal in high humidity environments.

Selective activation of dioxygen to singlet oxygen over La-Si co-doped TiO2 microspheres for photocatalytic degradation of formaldehyde

Volatile Organic Compounds (VOCs) are highly harmful to human beings and other organisms, and thus the elimination of VOCs is extremely urgent. Here, La-Si co-doped TiO2 microsphere photocatalysts, which were prepared by a hydrothermal method, exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO2. The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers, as verified by the electrochemical results in combination with density functional theory calculations. In addition, the Si dopant changed the microstructure and surface acidity, while the addition of La promoted the separation efficiency of charge carriers. More interestingly, it was found that singlet oxygen was the key species in the activation of molecular dioxygen, and it played a pivotal role in the photocatalytic decomposition of formaldehyde. This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.

Characterization and elimination efficiency of volatile organic compounds in mechanically recycled polyethylene terephthalate at various recycling stages

The recycling of polyethylene terephthalate (PET) stands as an effective strategy for mitigating plastic pollution and reducing resource waste. The study aimed to investigate the characterization and elimination efficiency of volatile organic compounds (VOCs) present in rPET at various recycling stages using comprehensive two-dimensional gas chromatography-quadrupole-time-of-flight-mass spectrometry coupled with chemometrics. The results revealed that 52, 135, 95, 44, and 33 VOCs, mostly classified into three chemical groups, were tentatively identified in virgin − PET (v-PET), cold water washed − rPET (C-rPET), decontaminated − rPET (D-rPET), melt-extruded − rPET (M-rPET), and solid-state polycondensation − rPET (S-rPET), respectively. Regarding the VOCs with high and median detection frequencies, fatty acyls showed the highest elimination efficiency (100 % and 92 %), followed by organooxygen compounds (81 % and 99 %), others (97 % and 95 %), and benzene and substituted derivatives (82 % and 95 %) in term of HS-SPME. Following the recycling process, there was a general decrease in the concentration of almost all VOCs, as evidenced by the substantial reduction of o-Xylene, hexanoic acid, octanal, and D-limonene from 18.11, 22.43, 30.74, and 7.41 mg/kg to 0, 0, 3.97, and 0 mg/kg, respectively. However, it was noteworthy that the VOCs identified in the samples were not completely extracted, owing to the limitations of HS-SPME. Furthermore, chemometrics analysis indicated significant discrimination among VOCs from vPET, C-rPET, D-rPET, and M-rPET, while indistinct differences were observed between M-rPET and S-rPET. This study contributes to the enhancement of the recycling process and emphasizes the importance of safeguarding consumer health in terms of elimination of VOCs.

A theoretical study on toluene oxidization by OH radical

Toluene, a prominent member of volatile organic compounds (VOCs), exerts a substantial adverse influence on both human life and the environment. In the context of advanced oxidation processes, the ·OH radical emerges as a highly efficient oxidant, pivotal in the elimination of VOCs. This study employs computational quantum chemistry methods (G4MP2//B3LYP/6-311++G(d,p)) to systematically investigate the degradation of toluene by ·OH radicals in an implicit solvent model, and validates the rationale of choosing a single-reference method using T1 diagnostics. Our results suggest three possible reaction mechanisms for the oxidation of toluene by ·OH: firstly, the phenyl ring undergoes a hydrogen abstraction reaction followed by direct combination with ·OH to form cresol; secondly, ·OH directly adds to the phenyl ring, leading to ring opening; thirdly, oxidation of sidechain to benzoic acid followed by further addition and ring opening. The last two oxidation pathways involve the ring opening of toluene via the addition of ·OH, significantly facilitating the process. Therefore, both pathways are considered feasible for the degradation of toluene. Subsequently, the UV-H2O2 system was designed to induce the formation of ·OH for toluene degradation and to identify the optimal reaction conditions. It was demonstrated that ·OH and 1O2 are the primary active species for degrading toluene, with their contribution ranking as ·OH > 1O2. The intermediates in the mixture solution after reactions were characterized using GC–MS, demonstrating the validity of theoretical predictions. A comparative study of the toluene consumption rate revealed an experimental comprehensive activation energy of 10.33 kJ/mol, which is consistent with the preliminary activation energies obtained via theoretical analysis of these three mechanisms (0.56 kJ/mol to 13.66 kJ/mol), indicating that this theoretical method can provide a theoretical basis for experimental studies on the oxidation of toluene by ·OH.

Engineering lattice oxygen mobility and optimizing reaction pathway via tuning Cu-Co interactions for efficient elimination of volatile organic compounds: A metal–organic framework template approach

Incorporating a secondary metal into individual cobalt oxides has been viewed as an efficacious approach in creating intermetallic interactions. Nonetheless, the processes involved in the construction of intermetallic interactions, as well as the underlying mechanisms that contribute to catalytic activity, remain largely elusive in current scientific understanding. In this work, a range of Cu-Co bimetallic oxides were synthesized through various preparation methods, employing MOFs as templates. Notably, the hydrothermally-synthesized Cu/Co-HT catalyst exhibited impressive catalytic qualities for toluene combustion, with T50 = 229 °C and T90 = 239 °C, alongside exceptional stability and moisture resistance (under 10 vol. % of water) for at least 100 h. The optimal catalyst Cu/Co-HT is attributed to the stronger Cu-Co interaction, which leading to larger specific surface area and weaker Co-O bond strength. And it also affects the chemical properties, such as get more Co3+ and lattice oxygen species by a redox (Co2++Cu2+→Co3++Cu+), better electron transfer performance and low-temperature reducibility. In addition, the reaction mechanism of toluene over the surface of Cu/Co-HT was also revealed by in-situ DRIFTS. It was observed that the bimetallic catalyst, characterized by robust Cu-Co interactions, optimized the reaction pathway for toluene oxidation compared to pure Co3O4. This facilitation led to the direct conversion of benzyl alcohol into benzoate and carboxylate, thereby bypassing the intermediate step involving benzaldehyde, which enhancing the reaction speed, yielding a long-term stable and efficient operational performance. This study reveals that optimize the physicochemical properties of catalytic by enhancing bimetallic interactions is an effective strategy for improving catalytic behavior.

From Design to Applications: A Comprehensive Review on Porous Frameworks for Photocatalytic Volatile Organic Compounds (VOCs) Removal

AbstractVolatile organic compounds (VOCs) present significant and irreversible risks to both human health and the environment. Therefore, there is an urgent and important need for extensive research aimed at identifying suitable materials and effective technical approaches for VOC removal. Metal‐ and covalent organic frameworks (MOFs, COFs), along with covalent triazine frameworks (CTFs), represent an attractive class of porous materials characterized by adjustable structures, high porosity, and high specific surface areas. In recent years, these materials have rapidly advanced across various fields, including gas adsorption and separation, drug delivery, sensing, and heterogeneous catalysis. Notably, MOFs, COFs, and CTFs exhibit immense potential for the photocatalytic elimination of VOCs, since they behave as semiconductors with adjustable properties. This review offers an overview of the synthesis and structural relationships of MOFs, COFs, and CTFs while discussing the recent progress in photocatalytic VOC removal. Additionally, a comprehensive overview of the photocatalytic mechanism is presented. Finally, the current limitations and prospective future developments are discussed.

Synthesis and application of Al trimesate-based metal-organic framework: a critical review

This review comprehensively explores the synthesis and diverse applications of the Al trimesate-based metal-organic framework, MIL-96 (Al). It begins with an introduction to the structure and properties of MIL-96 (Al), followed by an in-depth discussion of various synthesis strategies, including hydrothermal, microwave irradiation, electrochemical, mechanochemical, and sonochemical methods. The paper then delves into environmental remediation applications, highlighting MIL-96 (Al)’s effectiveness in fluoride and heavy metal removal, as well as in the elimination of volatile organic compounds (VOCs) and CO2. The review further examines the role of MIL-96 (Al) in catalysis and its emerging significance in battery technology, showcasing its versatility and potential in sustainable energy solutions. Finally, the paper concludes with perspectives on future research directions, emphasizing the ongoing development and optimization of MIL-96 (Al) for environmental and energy-related applications.

Construction of Pd/Mn3O4 heterojunction catalyst for efficient photothermal synergetic catalytic propane total oxidation

Photothermal synergistic low-temperature catalytic volatile organic compounds (VOCs) degradation has an advantage on energy efficiency and reduction of carbon emissions. Herein, an impregnation-pyrolysis-oxidation strategy was adopted to synthesize Pd/Mn3O4 heterojunction catalyst. Under photothermal synergistic conditions, 0.60Pd/Mn3O4 catalyst exhibited an excellent activity for propane total oxidation, with a T90 value of 219.1 ℃, which was 115.3 ℃ lower than that of Mn3O4. Enhancement effect of the heterojunction structure on photothermal synergy was detected by various characterization techniques and density functional theory calculation. The presence of Pd species enhanced the low-temperature reducibility of Mn3O4. Meanwhile, O2 molecules were more easily activated at the Pd sites and overflow to the surface of Mn3O4 for reaction. Besides, the formation of p-n junction between Pd species and Mn3O4 in heterojunction structure promoted the charge separation and the migration of carriers, and boosted the generation of oxygen free radical, resulting in a significant improvement in photothermal catalytic activity. Overall, this study provided new strategy and deep insight for constructing heterojunction to enhance photothermal catalytic performance of VOC elimination.

A theoretical study of the oxidation of benzene by manganese oxide clusters: formation of quinone intermediates.

Manganese oxides (MnxOy) have been widely applied in various chemical industrial processes owing to their long lifetime, low cost and high abundance. They have been used as co-reactants for the elimination of volatile organic compounds (VOCs); however, their oxidation mechanism is not clearly established. In this theoretical study, interaction capacities between benzene (C6H6) and MnxOy clusters, which were modeled with MnO2 and Mn2O3 molecules, were investigated by quantum chemical computations using density functional theory (DFT) with the PBE-D3 functional. The interaction capacity between C6H6 and MnxOy was evaluated, and the probing of the initial stage of the C6H6 oxidation at a molecular level offers an in-depth oxidation reaction path. Interaction energies computed in several spin states, along with the analysis of the electron distribution using the quantum theory of atoms in molecules, natural bond orbital and Wiberg bond index techniques as well as local softness values and MO energies of fragments, point out that the interaction between C6H6 and Mn2O3 is stronger than that with MnO2, amounting to -43 and -35 kcal mol-1, respectively, and the metal atom is identified as the primary active site. During the oxide cluster-assisted oxidation, benzene firstly undergoes an oxidation reaction by active oxygen to generate intermediates such as hydroquinone and benzoquinone. The pathway involving p-benzoquinone as the product (noted as PR1) is the most energetically favored one through a transition structure lying at 19 kcal mol-1, below the energy reference of the reactants, leading to an energy barrier significantly lower than that of 36 kcal mol-1 found for the gas phase oxidation reaction with molecular oxygen without the assistance of the oxide clusters. Potential energy profiles illustrating the reaction paths and molecular mechanisms were described in detail.

Challenges and opportunities for zeolite-based catalysts in catalytic oxidation of volatile organic compounds

Challenges and opportunities for zeolite-based catalysts in catalytic oxidations of volatile organic compounds (VOCs), which have emerged as highly promising materials for the elimination of VOCs due to their unique features.

Kill two birds with one stone: simultaneous removal of volatile organic compounds and ozone secondary pollution by a novel photocatalytic process.

Volatile organic compounds (VOCs) originating from diverse sources with complex compositions pose threats to both environmental safety and human health. Photocatalytic treatment of VOCs has garnered attention due to its high efficacy at room temperature. However, the intricate photochemical reaction generates ozone (O3), causing secondary pollution. Herein, our work developed a novel "synergistic effect" system for photocatalytic co-treatment of VOCs and O3 secondary pollution. Under the optimized reactor conditions simulated with computational fluid dynamics (CFD), MgO-loaded g-C3N4 composites (MgO/g-C3N4) were synthesized as efficient catalysts for the photocatalytic synergistic treatment process. Density functional theory (DFT) calculations, characterization, and electron paramagnetic resonance (EPR) tests revealed that the addition of MgO reduced the band gap of g-C3N4, and increased O3 molecule adsorption in the composites, efficiently harnessing the synergistic effect of O3 to generate a significant quantity of reactive oxygen radicals, thereby facilitating the removal of VOCs and O3. This study provides new insights for simultaneous elimination of VOCs and O3 secondary pollution by a photocatalytic process.

Encapsulating platinum nanoparticles into multi-hollow silicalite-1 zeolite for catalytic oxidation of volatile organic compounds

Platinum nanoparticles (Pt NPs) embedded in the multi-hollow silicalite-1 zeolite (Pt@MH-S-1) were prepared by the sequential alkali etching and recrystallization of parent microporous silicalite-1 zeolite. Then, toluene and acetone were employed as probe molecules to determine the catalytic behavior of Pt@MH-S-1 for the elimination of volatile organic compounds (VOCs). The results reveal that Pt@MH-S-1 with multi-hollow structure owns large external specific surface area for dispersing the Pt NPs, and abundant mesoporous channels for improving the accessibility of toluene to Pt NPs as well as high reactive oxygen content, excellent toluene adsorption capacity and moderate adsorption strength. Owing to these characteristics, Pt@MH-S-1 exhibits superior performance both in toluene and acetone catalytic oxidations as reflected by 100% conversion acquired at even a low temperature of 137 and 180 °C, respectively. Moreover, Pt@MH-S-1 also shows good stability toward the various conditions, signifying its superiority and potential in practical application for VOCs treatment.

Efficient Exciton Dissociation on Ceria Chelated Cerium-Based MOF Isogenous S-Scheme Photocatalyst for Acetaldehyde Purification.

Long-term exposure to low concentration indoor VOCs of acetaldehyde (CH3CHO) is harmful to human health. Thus, a novel isogenous heterojunction CeO2/Ce-MOF photocatalyst is synthesized via a one-step hydrothermal method for the effective elimination of CH3CHO in this work. This CeO2/Ce-MOF photocatalyst performs well in CH3CHO removal and achieves an apparent quantum efficiency of 7.15% at 420nm, which presents ≈6.7 and 3.4times superior to those generated by CeO2 and Ce-MOF, respectively. The enhanced efficiency is due to two main aspects including i) an effective photocarrier separation ability and the prolonged reaction lifetime of excitons play crucial roles and ii) the formation of an internal electric field (IEF) is sufficient to overcome the considerable exciton binding energy, and increases the exciton dissociation efficiency by up to 50.4%. Moreover, the reasonable pathways and mechanisms of CH3CHO degradation are determined by in situ DRIFTS analysis and simulated DFT calculations. Those results demonstrated that S-scheme heterojunction successfully increases the efficiency of harmful volatile organic compounds elimination, and it offers essential guidance for designing rare earth-based MOF photocatalysts.

Catalytic Combustion of Volatile Organic Compounds (VOCs) over Perovskite Oxides: A Review

Volatile organic compounds (VOCs) are one of the crucial outdoor as well as indoor air pollutants. Recently, the elimination of volatile organic compounds is become more attractive due to its potentiality of long-term human health effects. Among the different existing methods for the removal of VOCs, the catalytic combustion is the best convenient method due to its operational simplicity, cost effectiveness, high efficiency and industrial acceptability. Various perovskite oxides have been widely studied as suitable catalysts for the removal of VOCs because of their tunable physico-chemical properties, compositional/structural exibility and high thermochemical stability. The morphology, material composition and surface as well as bulk properties of perovskite oxides is the key determining factors for catalytic efficiency. The suitable metal or non-metal doping, controlling morphology (nano-structuring, three-dimensional ordered microporous (3DOM) building) and hybrid construction (perovskite as support for other active catalysts and other oxides as support for active perovskite catalyst) may have a remarkable effect on the surface as well as bulk properties and consequently the catalytic efficiency for ther removal reactions of VOCs are also effected. In this review article, different aspects of the current development in perovskite oxides catalysts for VOCs combustion with a special highlighting on the material designing, like doping, morphology controlling, surface modication and hybrid construction are presented.

Light-driven photothermocatalytic performance of the Pt/Co3O4 catalyst for toluene oxidation

Light-driven photothermocatalytic oxidation is a promising method for the elimination of volatile organic compounds (VOCs). The Co3O4, 0.46 Pt/Co3O4 and 0.97 Pt/Co3O4 catalysts were fabricated via the simple molten salt and incipient wetness impregnation method. Compared with Co3O4 and 0.46 Pt/Co3O4, the 0.97 Pt/Co3O4 catalyst showed higher photothermocatalytic performance for toluene oxidation under simulated solar irradiation intensity of 900 ​mW ​cm−2, with the toluene conversion and CO2 yield being up to 98.3 % and 96.0 %, respectively. The better activity was ascribed to its outstanding strong light absorption and low temperature reducibility. Meanwhile, 0.97 Pt/Co3O4 also exhibited an excellent photothermocatalytic stability and H2O resistance. The Vis−IR light played a key role in the photothermocatalytic oxidation of toluene in the whole solar spectrum. This work benefited the synthesis of catalysts with good photothermocatalytic activity for environment friendly treatment of VOCs.

Fabrication of highly dispersed Pd-Mn3O4 catalyst for efficient catalytic propane total oxidation

Adjusting the interaction between dual active components for enhancing volatile organic compounds (VOCs) degradation is an effective but still challenging means of air pollution control. Herein, a limited pyrolysis oxidation strategy was adopted to prepare Pd-Mn3O4 spinel catalysts with uniform morphology and active component dispersion. Among these, 1.08Pd-Mn3O4 presented the highest catalytic efficiency with a T90 value of 240 °C, which was 94 °C lower than that of Mn3O4. Characterization and density functional theory (DFT) calculation results revealed that the strong metal-support interaction (SMSI) effect between Pd and Mn3O4 promoted the redistribution of surface charges, thus strengthening the oxidation-reduction ability of the active sites. Moreover, the SMSI effect led to a better migration of surface oxygen species, and boosted the generation of active surface oxygen species. Simultaneously, the Pd catalyst further reduced the energy barrier in the initial stage of the dehydrogenation of propane. Overall, this study provided a novel design strategy for dual active components catalysts with SMSI effect and extended the application of these catalysts in the important field of VOCs elimination.

Toluene decomposition by non-thermal plasma assisted CoOx − γ-Al2O3: The relative contributions of specific energy input of plasma, Co3+ and oxygen vacancy

Cobalt oxide (CoOx) is a common catalyst for plasma catalytic elimination of volatile organic compounds (VOCs). However, the catalytic mechanism of CoOx under radiation of plasma is still unclear, such as how the relative importance of the intrinsic structure of the catalyst (e.g., Co3+ and oxygen vacancy) and the specific energy input (SEI) of the plasma for toluene decomposition performance. CoOx − γ-Al2O3 catalysts were prepared and evaluated by toluene decomposition performance. Changing the calcination temperature of the catalyst altered the content of Co3+ and oxygen vacancies in CoOx, resulting in different catalytic performance. The results of the artificial neural network (ANN) models presented that the relative importance of three reaction parameters (SEI, Co3+, and oxygen vacancy) on the mineralization rate and CO2 selectivity were as follows: SEI > oxygen vacancy > Co3+ , and SEI > Co3+ > oxygen vacancy, respectively. Oxygen vacancy is essential for mineralization rate, and CO2 selectivity is more dependent on Co3+ content. Furthermore, a possible reaction mechanism of toluene decomposition was proposed according to the analysis results of in-situ DRIFTS and PTR-TOF-MS. This work provides new ideas for the rational design of CoOx catalysts in plasma catalytic systems.

SO2-tolerant mesoporous iron oxide supported bimetallic single atom catalyst for methanol removal

Among the single-atom catalysts (SACs), the bimetallic single-atom catalysts play an increasingly promising role in the oxidative removal of volatile organic compounds (VOCs) due to their high efficiency. However, it remains a significant challenge to resist SO2 poisoning in industrial applications. In this work, we report (i) the synthesis of three-dimensionally ordered mesoporous Fe2O3-supported bimetallic AuPt single-atom (denote as Au1Pt1/meso-Fe2O3) catalyst via a modified polyvinyl alcohol-protected reduction route; (ii) catalytic performance of the catalysts for methanol oxidation; and (iii) catalytic and SO2-resistant mechanism. It was found that compared with Pt1/meso-Fe2O3 and Ptnp/meso-Fe2O3, Au1Pt1/meso-Fe2O3 exhibited better catalytic activity for methanol combustion, with the temperature at 90% methanol conversion, TOFnoble metal at 120 °C, and apparent activation energy being 137 °C at a space velocity of 20 000 mL g–1 h–1, 6.51 × 10–2 s–1, and 36 kJ mol− 1, respectively. The enhanced activity was associated with the improved reducibility, methanol adsorption ability, and strong interaction between noble metal and support. The reaction pathway was deduced to follow a sequence of methanol → methoxy species → formaldehyde → formic acid → CO2 and H2O. Furthermore, the order of SO2 resistance was Au1Pt1/meso-Fe2O3 > Pt1/meso-Fe2O3 > Ptnp/meso-Fe2O3. The good SO2 resistance of the Au1Pt1/meso-Fe2O3 catalyst was attributed to the Au−Pt bimetallic single atoms uniformly dispersed on the meso-Fe2O3 with the strong ability of sulfate decomposition and the protection of the active sites by meso-Fe2O3 as a sacrificial site. This work presents a novel way for developing high-performance catalysts for VOCs elimination in the presence of SO2.

Engineering of oxygen vacancy defect in CeO2 through Mn doping for toluene catalytic oxidation at low temperature

Catalytic oxidation is considered a highly effective method for the elimination of volatile organic compounds. Oxygen vacancy defect engineering in a catalyst is considered an effective approach for high-performance catalysts. Herein, a series of doped MnxCe1-xO2 catalysts (x = 0.05–0.2) with oxygen vacancy defects were synthesized by doping low-valent Mn in a CeO2 lattice. Different characterization techniques were utilized to inspect the effect of doping on oxygen vacancy defect generation. The characterization results revealed that the Mn0.15Ce0.85O2 catalyst has the maximum oxygen vacancy concentration, leading to increased active oxygen species and enhanced oxygen mobility. Thus, Mn0.15Ce0.85O2 catalyst showed an excellent toluene oxidation activity with 90% toluene conversion temperature (T90) of 197 °C at a weight hourly space velocity of 40,000 mL g−1 h−1 as compared to undoped CeO2 (T90 = 225 °C) and Ce based oxides in previous reports. In addition, the Mn0.15Ce0.85O2 catalyst displayed strong recyclability, water resistant ability and long-time stability. The in situ DRIFT results showed that the Mn0.15Ce0.85O2 catalyst has a robust oxidation capability as toluene is quickly adsorbed and actuated as compared to CeO2. Thus, the present work lays the foundation for designing a highly active catalyst for toluene elimination from the environment.

Supercritical co2 deodorization of dried pork liver

Pork liver has excellent nutritional properties but is a highly perishable product often rejected by consumers due to its strong unpleasant flavour. The objective of this study was to analyze the feasibility of the deodorization and defatting of dried pork liver by means of supercritical CO2 (SC-CO2) and conventional vacuum steam distillation (VSD).The results showed that both deodorization techniques were effective at reducing volatile organic compounds (VOCs). Through VSD, the VOC content was reduced by 67.6% UA, while an 81.3% UA reduction was achieved by SC-CO2, with respect to dried pork liver. In addition, 3 characteristic compounds of raw pork liver were completely eliminated by applying SC-CO2, which could potentially reduce the characteristic mushroom (1-octen-3-ol), fatty and green (1-nonanol), and fishy ((E,E)− 2,4-heptadienal) off-flavours. Therefore, SC-CO2 could be considered a promising technique for the elimination of VOCs, and furthermore it leads to a reduction in the fat content (24.9%).