Dust Particles Research Articles

Sensitivities of Spectral Optical Properties of Dust Aerosols to Their Mineralogical and Microphysical Properties

AbstractDust aerosol is a key component in global radiative forcing and climate modeling. We developed a mineralogy‐resolved spectral optical property model for dust aerosols. The model incorporates nine mineral groups and applies the effective medium methods to obtain the spectral complex refractive indices of inhomogeneous dust particles. This study considers 5,000 sets of dust mineral composition mixtures along with the use of the bimodal particle size distribution. We calculate the bulk properties of these samples in a wide spectral range from 0.2 to 50 μm using a comprehensive database of hexahedral dust single‐scattering properties. Through sensitivity analyses, this study reveals that the illite and hematite components substantially affect the optical properties of dust. Furthermore, the effective radii of both the fine‐mode and the coarse‐mode dust particles have significant impacts on the bulk optical properties, albeit to varying degrees.

Dust dynamics: distribution patterns of semi-volatile organic chemicals across particle sizes in varied indoor microenvironments.

An extensive analysis of the distribution patterns of three distinct classes of semi-volatile organic chemicals (SVOCs)-phthalates (PAEs), organophosphate flame retardants (OPFRs), and polycyclic aromatic hydrocarbons (PAHs)-across four distinct size fractions of dust (25, 50, 100, and 200μm) was conducted. The dust samples were sourced from AC filter, covered car parking lots, households, hotels, mosques, and car floors. To generate the four fractions, ten dust samples from each microenvironment were pooled and sieved utilizing sieving apparatus with the appropriate mesh size. Selected SVOCs were quantified utilizing gas chromatography-mass spectrometry in electron impact (EI) mode. Results unveiled diverse contamination levels among dust fractions, showcasing car parking lot dust with the lowest chemical contamination, while car floor dust displayed the highest levels of PAHs and OPFRs, peaking at 28.3µg/g and 43.2µg/g, respectively. In contrast, mosque and household floor dust exhibited the highest concentrations of phthalates, with values of 985µg/g and 846µg/g, respectively. Across the analyzed microenvironments, we observed a trend where concentrations of SVOCs tended to rise as dust particles decreased in size, forming a visually striking pattern. This phenomenon was particularly pronounced in dust samples collected from car floors and parking lots. Among SVOCs, PAEs emerged as the predominant contributors with > 90% followed by OPFRs and PAHs. The high levels of OPFRs in car floor dust align logically with the fact that numerous interior components of cars are treated with OPFRs, within a compact indoor microenvironment, to comply to fire safety regulations. Furthermore, petroleum products are a major source of PAHs in the environment and all the sampled cars in the study had combustion engines. Consequently, car dust is more likely to be polluted with PAHs stemming from petroleum combustion. Although previous investigations have noted an increase in heavy metals and brominated flame retardants with decreasing dust particles, this is the first study analyzing these SVOCs in different fractions of dust from various microenvironments. However, aside from two specific microenvironments, the observed pattern of escalating SVOC concentrations with smaller dust particle sizes was not corroborated among the examined microenvironments. This divergence in concentration trends suggests the potential involvement of supplementary variables in influencing SVOC distributions within dust particles.

VLC channel model in underground mining scenarios with the extinction effect and shadowing effect

In this work, a novel, to our knowledge, visible light communication (VLC) channel model is proposed for underground mining scenarios taking into account the impact of coal dust particles and obstacles. Specifically, the extinction effect of the coal dust particles is analyzed on the basis of the Mie theory, and the quantitative formula of the influence on channel direct current (DC) gain is derived. Meanwhile, the effect of a random shadowing phenomenon is investigated and quantified with the geometric and statistical model considering the position, size, and shape of the obstacles. The channel impulse response, path loss, root mean square delay spread, and bit error rate (BER) are further investigated in two different underground mining scenarios, namely, a mining roadway and coal mine working face. Simulation results show that the shadowing effect plays a major role in the influence of DC gain attenuation. Furthermore, the BER performance is noticeably degraded due to the presence of coal dust particles and obstacles, especially when the receiver is located far from the transmitter. This work will benefit the design of the VLC systems in underground mines.

The lunar dust environment: concerns for Moon-based astronomy.

The Moon has no atmosphere, hence, it offers a unique opportunity to place telescopes on its surface for astronomical observations. It is phase-locked with Earth, and its far side remains free from ground-based interference, enabling the optimal use of radio telescopes. However, the surface of the Moon, as any other airless planetary object in the solar system, is continually bombarded by interplanetary dust particles that cause impact damage and generate secondary ejecta particles that continually overturn the top layer of the lunar regolith. In addition, there is evidence, that small particles comprising the lunar regolith can be electrically charged, mobilized and transported, also representing a hazard for covering sensitive surfaces and interfering with exposed mechanical structures. In addition to the naturally occurring dust transport, rocket firings during landings and take-offs, pedestrian and motorized vehicle traffic will also liberate copious amounts of dust, representing a potential hazard for the safe and optimal use of optical platforms. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

Design and Analysis of Fugitive Dust Emission Collector

This creative project explores the design and analysis of a novel fugitive dust emission collector, with a focus on its application in stone crusher units and crematorium facilities. Recognizing the detrimental health and environmental impacts of dust emissions, this project proposes a multifaceted approach. The core solution involves a combined system, this captures and removes larger dust particles through established methods like cyclones or bag houses. Dry fog dust suppression system, this technology utilizes atomized water droplets to suppress smaller fugitive dust particles, preventing their airborne spread. This project delves into the specific needs of stone crusher units and crematorium facilities. Utilizing CAD software, 3D models of the emission collector will be created, incorporating considerations like material selection, efficiency and airflow optimization, integration with existing infrastructure. Computational fluid dynamics (CFD) analysis by Simulating airflow patterns and dust capture efficiency within the collector. Assessing the collector's ability to withstand operational loads and environmental factors. This project aims to achieve, reduced fugitive dust emissions, enhanced environmental compliance, improved operational efficiency. Overall, this creative project showcases an innovative approach to fugitive dust control, potentially leading to improved environmental and public health outcomes in diverse industrial settings

Characterization of the airborne aerosol inlet and transport system used during the A-LIFE aircraft field experiment

Abstract. Atmospheric aerosol particles have a profound impact on Earth's climate by scattering and absorbing solar and terrestrial radiation and by impacting the properties of clouds. Research aircraft such as the Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) Falcon are widely used to study aerosol particles in the troposphere and lower stratosphere. However, transporting a representative sample to the instrumentation inside the aircraft remains a challenge due to high airspeeds and changing ambient conditions. In particular, for high-quality coarse-mode aerosol measurements, knowledge about losses or enhancements in the aerosol sampling system is crucial. In this study, the sampling efficiency of the aerosol inlet aboard the Falcon research aircraft is characterized for the first time with state-of-the art in situ measurements including sizing instruments operated behind the Falcon aerosol inlet and mounted at the aircraft wing not affected by the aerosol inlet. Sampling efficiencies were derived for different true airspeed ranges by comparing the in-cabin and ”full”-size-range particle number size distributions during 174 flight sequences with a major contribution of mineral dust particles during the ”Absorbing aerosol layers in a changing climate: aging, lifetime and dynamics” project (A-LIFE). Additionally, experimentally derived Stokes numbers were used to calculate the cutoff diameter of the aerosol sampling system for different particle densities as a function of true airspeed. As expected, the results show that the velocity of the research aircraft has a major impact on the sampling of coarse-mode aerosol particles with in-cabin instruments. For true airspeeds up to about 190 m s−1, aerosol particles larger than about 1 µm are depleted in the sampling system of the Falcon during the A-LIFE project. In contrast, for true airspeeds higher than 190 m s−1, an enhancement of particles up to a diameter of 4 µm is observed. For even larger particles, the enhancement effect at the inlet is still present, but inertial and gravitational particle losses in the transport system get more and more pronounced, which leads to a decreasing overall sampling efficiency. In summary, aerosol particles are either depleted or enhanced in the Falcon aerosol inlet, whereas transport in sampling lines always leads to a loss of particles. Here, we have considered both effects and determined the cutoff diameter for the A-LIFE transport system (i.e., the sampling lines only), the cutoff diameter of the Falcon aerosol inlet (i.e., the effect of the inlet only), and the combined effect of the inlet and sampling lines.

Inhibition effect of inert gas jet on gas and hybrid explosions caused by thermal runaway of lithium-ion battery

When lithium-ion batteries undergo thermal runaway in a confined space, the released gases and/or vapors or dust particles can lead to an explosion. An 8L cylindrical experimental vessel was constructed to study the inert effect of inert gases on battery-vented gas (BVG) in a confined vessel. Firstly, the inhibition effect and inert mechanism of CO2 and N2 on BVG explosion were analyzed by experiments and simulation software. The results show that the inert effect of CO2 on the BVG is significantly better than that of N2. This is because CO2 is not only better than N2 in physical explosion inhibition, but also participates in the chemical reaction. Secondly, the effect of the release of high-pressure CO2 gas on the explosion of the BVG in a closed container was simulated, showing that when the BVG is near the lower explosive limit, the CO2 jet will significantly increase the rate of explosion pressure rise of the BVG. This suggests that the inhibition effect of the CO2 jet is not as good as in premixed conditions. Finally, it is found that the inhibition effect of CO2 on the hybrid explosion is better than that of CO2 jet on the BVG. Since CO2 makes oxygen insufficient, leading to a reduction in the amount of graphite dust burned. The graphite dust and CO2 have a synergistic inhibition effect on the hybrid explosion. The above findings can provide a reference for the lithium-ion battery explosion inhibition method in the process industry.

Self-Powered Autonomous Electrostatic Dust Removal for Solar Panels by an Electret Generator.

Solar panels often suffer from dust accumulation, significantly reducing their output, especially in desert regions where many of the world's largest solar plants are located. Here, an autonomous dust removal system for solar panels, powered by a wind-driven rotary electret generator is proposed. The generator applies a high voltage between one solar panel's output electrode and an upper mesh electrode to generate a strong electrostatic field. It is discovered that dust particles on the insulative glass cover of the panel can be charged under the high electrical field, assisted by adsorbed water, even in low-humidity environments. The charged particles are subsequently repelled from the solar panel with the significant Coulomb force. Two panels covered with sand dust are cleaned in only 6.6min by a 15cm diameter rotary electret generator at 1.6ms-1 wind speed. Experimental results manifest that the system can work effectively in a wide range of environmental conditions, and doesn't impact the panel performance for long-term operation. This autonomous system, with its high dust removal efficiency, simplicity, and low cost, holds great potential in practical applications.

Dust storms from the Taklamakan Desert significantly darken snow surface on surrounding mountains

Abstract. The Taklamakan Desert (TD) is a major source of mineral dust emissions into the atmosphere. These dust particles have the ability to darken the surface of snow on the surrounding high mountains after deposition, significantly impacting the regional radiation balance. However, previous field measurements have been unable to capture the effects of severe dust storms accurately, and their representation on regional scales has been inadequate. In this study, we propose a modified remote-sensing approach that combines data from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite and simulations from the Snow, Ice, and Aerosol Radiative (SNICAR) model. This approach allows us to detect and analyze the substantial snow darkening resulting from dust storm deposition. We focus on three typical dust events originating from the Taklamakan Desert and observe significant snow darkening over an area of ∼ 2160, ∼ 610, and ∼ 640 km2 in the Tien Shan, Kunlun, and Qilian mountains, respectively. Our findings reveal that the impact of dust storms extends beyond the local high mountains, reaching mountains located approximately 1000 km away from the source. Furthermore, we observe that dust storms not only darken the snowpack during the spring but also in the summer and autumn seasons, leading to increased absorption of solar radiation. Specifically, the snow albedo reduction (radiative forcing) triggered by severe dust deposition is up to 0.028–0.079 (11–31.5 W m−2), 0.088–0.136 (31–49 W m−2), and 0.092–0.153 (22–38 W m−2) across the Tien Shan, Kunlun, and Qilian mountains, respectively. This further contributes to the aging of the snow, as evidenced by the growth of snow grain size. Comparatively, the impact of persistent but relatively slow dust deposition over several months during non-event periods is significantly lower than that of individual dust events. This highlights the necessity of giving more attention to the influence of extreme events on the regional radiation balance. This study provides a deeper understanding of how a single dust event can affect the extensive snowpack and demonstrates the potential of employing satellite remote sensing to monitor large-scale snow darkening.

Are Clay Minerals Systematically the Products of Aqueous Alteration in Cosmic Bodies?

The formation of chondrite materials represents one of the earliest mineralogical processes in the solar system. Phyllosilicates are encountered at various stages of the chondrule formation, from the initial stages (IDP agglomerates) to the final steps (chondrule internal alteration). While typically linked to aqueous alteration, recent studies reveal that phyllosilicates could precipitate directly from residual fluids in post-magmatic or deuteric conditions and under a wide range of temperatures, pressures, water/rock ratios, and H2/H2O ratio conditions. This study re-examined the formation of hydrated phyllosilicates in chondrules and associated fine-grained rims (FGRs) using published petrographical, mineralogical, and chemical data on carbonaceous chondrites. Given that chondrules originate from the melting of interplanetary dust particles, the water liberated by the devolatilization of primary phyllosilicates, including clay minerals or ice melting, reduces the melting temperature and leads to water dissolution into the silicate melt. Anhydrous minerals (e.g., olivine and diopside) form first, while volatile and incompatible components are concentrated in the residual liquid, diffusing into the matrix and forming less porous FGRs. Serpentine and cronstedtite are the products of thermal metamorphic-like mineral reactions. The mesostasis in some lobated chondrules is composed of anhydrous and hydrous minerals, i.e., diopside and serpentine. The latter is probably not the alteration product of a glassy precursor but rather a symplectite component (concomitant crystallization of diopside and serpentine). If so, the symplectite has been formed at the end of the cooling process (eutectic-like petrographical features). Water trapped inside chondrule porosity can lead to the local replacement of olivine by serpentine without external water input (auto-alteration). In the absence of water, hydrated phyllosilicates do not crystallize, forming a different mineral assemblage.

Height-modulating horizontal transport of dust particles in a dusty plasma ratchet

Abstract Dust particles are often electrostatically trapped and levitated within the non-electroneutral region of a sheath. The fascinating transport phenomena of dust particles strongly depend on the plasma parameters surrounding them within the sheath, whereas, that are quite difficult to obtain, leading to an unclear understanding of particle transport mechanisms. Here, we demonstrate a tunable horizontal transport of micron-sized dust particles by precisely manipulating their vertically suspended heights in an asymmetric ratchet sheath by designing dusty plasma ratchet. A collection of dust particles serves as micro-probes to detect the height-dependent transport properties and the feature of the sheath. Two methods are employed to lift or reduce the suspended heights of dust particles while maintaining the sheath unchanged. As the suspended heights of dust particles vary, their directional transport changes accordingly, including a flow reversal. A two-dimensional (2D) model of the ratchet sheath depicts the nonlinear distributions of plasma parameters and reveals that these unexpected transport phenomena can be attributed to the dependence of the electric ratchet potential and the resulting non-equilibrium net ion drag force on the suspended heights of dust particles. Our combined experimental and theoretical study provides insights into the fundamental transport properties of dust particles in an asymmetrical sheath.

Exogenous Carbon is Unlikely to be the Source of Methane Microseepage Emissions on Mars

A complete understanding of methane in the atmosphere of Mars requires information on putative sources. Organic carbon derived from meteoritic sources, such as interplanetary dust particles (IDPs), over geologic time is the best-defined source of organic carbon on the surface of Mars. Here we examine two different mechanisms for degrading this material to produce methane (1) Ultraviolet photolysis and (2) thermal decomposition. Neither of these mechanisms can produce sufficient methane under realistic assumptions to explain observed methane at Gale Crater, suggesting that IDPs are not the primary source material producing methane on Mars.

Chondrule Destruction via Dust Collisions in Shock Waves

A leading candidate for the heating source of chondrules and igneous rims is shock waves. This mechanism generates high relative velocities between chondrules and dust particles. We have investigated the possibility of the chondrule destruction in collisions with dust particles behind a shock wave using a semianalytical treatment. We find that the chondrules are destroyed during melting in collisions. We derive the conditions for the destruction of chondrules and show that the typical size of the observed chondrules satisfies the condition. We suggest that the chondrule formation and rim accretion are different events if they are heated by shock waves.

A combined toxicological impact on Artemia salina caused by the presence of dust particles, microplastics from cosmetics, and paracetamol

Environmental pollution poses a significant and pressing threat to the overall well-being of aquatic ecosystems in modern society. This study showed that pollutants like dusts from AC filter, fan wings and Traffic dust PM 2.5 were exposed to Artemia salina in pristine form and in combination. The findings indicated that exposure to multi-pollutants had a detrimental effect on the hatching rates of A. salina cysts. Compared to untreated A. salina, the morphology of adult (7th day old) A. salina changed noticeably after each incubation period (24–120 h). Oxidative stress increased considerably as the exposure duration increased from 24 to 120 h compared to the control group. There was a time-dependent decline in antioxidant enzyme activity and total protein concentration. When all particles were used all together, the total protein content in A. salina decreased significantly. All particles showed a considerable decline in survival rate. Those exposed to traffic dust particles showed significantly higher levels of oxidative stress and antioxidant activity than those exposed to other particles.

Reduction of dust radial drift by turbulence in protoplanetary disks

Context. Dust particles in protoplanetary disks rotate at velocities exceeding those of the surrounding gas due to a lack of pressure support. Consequently, they experience a headwind from the gas that drives them toward the central star. Radial drift occurs on timescales much shorter than those inferred from disk observations or those required for dust to aggregate and form planets. Additionally, turbulence is often assumed to amplify the radial drift of dust in planet-forming disks when modeled through an effective viscous transport. However, the local interactions between turbulent eddies and particles are known to be significantly more intricate than in a viscous fluid. Aims. Our objective is to elucidate and characterize the dynamic effects of Keplerian turbulence on the mean radial and azimuthal velocities of dust particles. Methods. We employed 2D shearing-box incompressible simulations of the gas, which is maintained in a developed turbulent state while rotating at a sub-Keplerian speed. Dust is modeled as Lagrangian particles set at a Keplerian velocity, therefore experiencing a radial force toward the star through drag. Results. Turbulent eddies are found to reduce the radial drift, while simultaneously enhancing the azimuthal velocities of small particles. This dynamic behavior arises from the modification of dust trajectories due to turbulent eddies.

Distribution of 35 Polycyclic Aromatic Hydrocarbons in Pine Needle Samples from Selected Locations in the Republic of Korea.

Polycyclic aromatic hydrocarbons (PAHs), dust, and wax were measured in pine needles, and PAHs were also measured in surface soil. Pearson correlation analysis was performed between the analytical values. The main compounds responsible for the increase in total PAHs were non-carcinogenic phenanthrene and fluoranthene. Therefore, the % content of carcinogenic PAHs decreased with a slope = -0.037 (r = 0.47, p < 0.01), as the total PAH concentration in pine needles increased. Correlations between individual PAHs in pine needles and surface soil were very high when only low-number ring PAHs (2R- and 3R-PAHs) were statistically analyzed and significant when only high-number ring PAHs were statistically analyzed. Low-number ring PAH mainly moves in the gas phase and diffuses into the wax layer, so it was found to be statistically significant with the wax content of pine needles. High-number ring PAHs showed a high correlation with the amount of dust in pine needles because they mainly attached to dust particles and accumulated on the surface of pine needles. The ratios of fluoranthene/pyrene and methylphenanthrene/phenanthrene for predicting the origin of atmospheric PAHs have also been proven valid for pine needles.

Key drivers of the oxidative potential of PM2.5 in Beijing in the context of air quality improvement from 2018 to 2022

The mass concentration of atmospheric particulate matter (PM) has been continuously decreasing in the Beijing-Tianjin-Hebei region. However, health endpoints do not exhibit a linear correlation with PM mass concentrations. Thus, it is urgent to clarify the prior toxicological components of PM to further improve air quality. In this study, we analyzed the long-term oxidative potential (OP) of water-soluble PM2.5, which is generally considered more effective in assessing hazardous exposure to PM in Beijing from 2018 to 2022 based on the dithiothreitol assay and identified the crucial drivers of the OP of PM2.5 based on online monitoring of air pollutants, receptor model, and random forest (RF) model. Our results indicate that dust, traffic, and biomass combustion are the main sources of the OP of PM2.5 in Beijing. The complex interactions of dust particles, black carbon, and gaseous pollutants (nitrogen dioxide and sulfur dioxide) are the main factors driving the OP evolution, in particular, leading to the abnormal rise of OP in Beijing in 2022. Our data shows that a higher OP is observed in winter and spring compared to summer and autumn. The diurnal variation of the OP is characterized by a declining trend from 0:00 to 14:00 and an increasing trend from 14:00 to 23:00. The spatial variation in OP of PM2.5 was observed as the OP in Beijing is lower than that in Shijiazhuang, while it is higher than that in Zhenjiang and Haikou, which is primarily influenced by the distribution of black carbon. Our results are of significance in identifying the key drivers influencing the OP of PM2.5 and provide new insights for advancing air quality improvement efforts with a focus on safeguarding human health in Beijing.

Dedusting and inhibition of methane-coal dust hybrid explosion by ultrafine water mist containing SDS surfactant

The dust reduction and inhibition effects of ultrafine water mist containing SDS anionic surfactant on methane-coal dust explosion were experimentally investigated. Compared with pure ultrafine water mist, the Pmax and (dP/dt) max of 0.5% SDS water mist were reduced by 9.18% and 27.2%, respectively, and the explosion induction period was prolonged from 102 ms to 205 ms. SDS water mist can effectively inhibit the intensity and propagation of the flame, forming the formation of irregular fronts and unevenly colored orange flames after multiple extinguishments in the explosion induction period. In addition, the addition of SDS surfactant promotes the formation of liquid bridges between water mist and coal dust particles. The contact angle of coal dust is reduced by 38.9% and the sink time is reduced to 30 ms. This paper presents a new direction and choice for achieving simultaneous dust reduction and explosion suppression in coal mines.

Distinguishing the contributions of different smelting emissions to the spatial risk footprints of toxic elements in soil using PMF, Bayesian isotope mixing models, and distance-based regression

Toxic element pollution of soils emanating from smelting operations is an escalating global concern due to its severe impact on ecosystems and human health. In this study, soil samples were collected and analyzed to quantify the risk contributions and delineate the spatial risk footprints from smelting emissions for 8 toxic elements. A comprehensive health risk contribution and delineation framework was utilized, consisting of Positive matrix factorization (PMF), spatial interpolation, an advanced Bayesian isotope mixing model via Mixing Stable Isotope Analysis in R (MixSIAR), and distance-based regression. The results showed that the mean concentrations of As, Cd, Cu, Hg, Pb, and Zn exceeded the background levels, indicating substantial contamination. Three sources were identified using the PMF model and confirmed by spatial interpolation and MixSIAR, with contributions ranked as follows: industrial wastewater discharge and slag runoff from the smelter site (48.9 %) > natural geogenic inputs from soil parent materials (26.7 %) > atmospheric deposition of dust particles from smelting operations (24.5 %). Among the identified sources, smelter runoff posed the most significant risk, accounting for 97.9 % of the non-carcinogenic risk (NCR) and 59.9 % of the carcinogenic risk (CR). Runoff also drove NCR and CR exceedances at 7.8 % and 4.7 % of sites near the smelter, respectively. However, atmospheric deposition from smelting emissions affected soils across a larger 0.8 km radius. Although it posed lower risks, contributing just 1.1 % to NCR and 22.6 % to CR due to the limited elevation of toxic elements, deposition reached more distant soils. Spatial interpolation and distance-based regression delineated high NCR and CR exposure hotspots within 1.4 km for runoff and 0.8 km for deposition, with exponentially diminishing risks at further distances. These findings highlight the need for pathway-specific interventions that prioritize localized wastewater containment and drainage controls near the smelter while implementing broader regional air pollution mitigation measures.

Experimental and kinetic analysis of the fluorocarbon structures and coal particles at the microscale

Understanding the dynamic wetting process between liquid droplets and coal dust particles is crucial. Compared to other substances, coal possesses a more intricate microscale molecular chemical structure, with coal's molecular chemical and physical structural characteristics being the primary microscale factors influencing its wetting properties. To enhance the wetting and permeability performance of coal dust, an analysis of the microstructural influences on the wetting process of coal dust through experiments and simulations with five different structured fluorocarbon solutions: perfluorooctane sulfonate sodium (A1), perfluoroisopropyl acrylate (A2), perfluorooctane sulfonic acid ammonium salt (A3), perfluorooctyl alcohol polyoxyethylene ether (N1), and perfluorohexyl ethanol polyoxyethylene ether (N2), was conducted. A wetting theory model (collision–adsorption–immersion) was proposed based on experiments with different concentrations and types of surface tension, and wetting experiments were conducted based on this theory model. The results indicate that smaller coal particle sizes facilitate solution penetration, with the N2 solution demonstrating the best wetting and permeation effects. Microstructural experimental analysis revealed that N2 has more polar functional group structures than the other four fluorocarbon solutions. To further investigate the forces of different structures on coal particles, a molecular dynamics model was employed, and the simulation results indicated that the interaction forces and the number of hydrogen bonds representing the adsorption capacity in the N2 system were the highest.