Global challenges such as health crises, rising sea levels, deforestation and biodiversity loss are linked to climate change, which is primarily caused by carbon dioxide (CO2) emissions. To address these issues, research into CO2 capture and reuse has gained prominence. Abundant, non-toxic to humans and inexpensive, CO2 is a promising raw material for energy and material production. However, converting CO2 into value-added products requires innovative approaches, such as the development of synthetic materials and catalytic processes. This study focuses on the use of silica extracted from rice husk ash, an agricultural residue comprising 20% of raw rice mass, as a support for metals such as cobalt (Co) and iron (Fe). The supported materials were evaluated for CO2 sorption and their catalytic performance in the direct synthesis of dimethyl carbonate (DMC) from methanol and CO2. Comprehensive characterization techniques, including field emission scanning electron microscopy (FE-SEM), surface area analysis (Brunauer-Emmett-Teller (BET) method), Fourier transform infrared spectroscopy with universal attenuated total reflectance (FTIR-UATR), solid-state nuclear magnetic resonance (NMR-MAS), temperature-programmed oxidationreduction (TPO), and temperature-programmed desorption (TPD), were employed. Catalytic performance was assessed using a Shimadzu GC 2014 gas chromatograph. The best CO2 sorption capacity was achieved with the sample Si-Co 10% (100 mg CO2 g(-1)) at 30 bar and 25 degrees C. The best conversion to DMC was for the sample Si-Fe 10% (22.91%), at 80 degrees C and 40 bar of CO2. This study demonstrates the potential of repurposing agricultural waste to extract silica and utilize it as a metal catalyst support, offering a promising solution for both CO2 capture and conversion.

The present study investigates the potential of dicationic ionic liquids (DILs) and monocationic ionic liquids (MoIL), with and without metal in the anion, for CO2 capture applications. The structures of the samples were confirmed by FTIR, 1H NMR spectroscopy, and Raman spectroscopy, while their physicochemical properties, density, viscosity, and thermal stability were evaluated. A series of computational simulations were conducted by using density functional theory (M11/def2-TZVP) to ascertain the multiplicity of the ground state of the magnetic anion [FeCl4]-. These simulations determined the multiplicity to be a sextet and furthermore identified the trans conformation as the most energetically favorable for cation [E(MIM)2]2+. This finding demonstrates a correlation between the structural conformations and the experimental Raman spectra. The findings of CO2 sorption and kinetic tests, conducted under postcombustion conditions (40 °C, 4 bar), indicated that DILs exhibited superior performance in comparison to MoILs. The DIL [E(MIM)2][2Cl] exhibited the highest sorption capacity (110.20 μmol/g), which is almost three times higher than that of the best MoIL (BMIM FeCl4). These enhancements can be ascribed to reduced viscosities and an augmented number of active interaction sites in the dicationic structures. Furthermore, [E(MIM)2][2Cl] exhibited a high degree of selectivity for CO2 over N2 and demonstrated stability over five recycling cycles, suggesting the potential of DILs as candidates for the development of CO2 capture technologies.

Gas separation employing polymeric membranes is limited by the permeability-selectivity trade-off, which has driven the development, among numerous technologies, of mixed matrix membranes (MMMs) that combine highly permeable polymers with fillers capable of enhancing gas selectivity. The compatibility in the filler/polymer interface is therefore essential to design materials with superior separation performances. In this work, MMMs were produced with Pebax-2533, incorporating synthetic silico-metallic mineral particles (SSMMPs) and SSMMP-NH2 fillers, both with and without PIM-1 surface coating, and were evaluated in the separation of CO2/CH4 and CO2/N2. The membranes were prepared in two types: dense and thin-film composite (TFC). These MMMs were characterized through several techniques, and gas permeation assessments of the dense membranes were conducted at pressures ranging from 1 to 10 bar. The findings demonstrated enhanced thermal, mechanical, and gas separation properties following the addition of the fillers. Specifically, the sample containing 20 wt % SSMMP-NH2@PIM-1 achieved a permeability of 501.7 Barrer at 10 bar, representing a 129.8% increase relative to the pure membrane. Additionally, the TFC membrane was fabricated using a self-made porous polysulfone (PSF) support, which was subsequently coated with a selective layer and a protective layer of polydimethylsiloxane (PDMS), achieving a CO2 permeance of 575 GPU and selectivities of 12 for CO2/CH4 and 33 for CO2/N2. The results demonstrated the beneficial effects of functionalizing the amine groups (-NH2) in the fillers, particularly when employing the nonsolvent-induced surface deposition (NISD) technique to coat PIM-1 on the filler surface. The developed materials exhibit promising performance as visualized in the Robeson graph and TFCs target regions, suggesting that they could be suitable for industrial-scale CO2 separation with additional development.

Polyurethane-based PILs were synthesized via in situ polymerization using different proportions (95%/5%, 90%/10%, and 80%/20%) of polycarbonate diol (PC) and polytetramethylene glycol (PG) as polyols, dimethylolpropionic acid (DMPA), and hexamethylene diisocyanate (HDI), with BMIM+ and TBP+ countercations. Gas permeability, CO2/N2 and CO2/CH4 ideal selectivity, and diffusion and solubility coefficients were determined. Computational simulations were conducted to elucidate the role of urethane moieties and TBP+/BMIM+ in CO2 capture. The PIL-PC95-PG5-TBP membrane exhibited the highest CO2 uptake (106.9 mg of CO2/g at 30 degrees C and 10 bar) and the highest CO2 permeability (38.9 barrer), while the BMIM-based membrane demonstrated superior ideal selectivity (CO2/CH4 = 52 and CO2/N2 = 82 at 4 bar). Computational simulation results confirmed the absence of chemisorption and highlighted opportunities to further enhance CO2 affinity in these membranes. PIL membranes showed enhanced CO2 permeability and selectivity compared to neat PUs and other PILs reported in the literature, demonstrating great potential for gas separation applications.

Mixed matrix membranes (MMMs) have been proposed as a solution to surmount Robeson's trade-off curves and have demonstrated efficacy in gas separation processes, particularly for CO2 capture. In this study, MMMs based on Pebax (R) 1657 were obtained utilizing synthetic silico-metallic mineral particles (SSMMP) functionalized with ionic liquids (ILs). The objective was to attain enhanced CO2 separation performance, thereby showcasing the potential to mitigate the environmental repercussions of industrial processes that entail greenhouse gas emissions. For membrane production, an ethanol/water mixture was used as solvent, with the SSMMP/IL content varying from 0.5 to 20% by weight of the polymer. The primary aim of this study was to assess the effect of filler addition on permeability and selectivity for CO2, CH4, and N-2. Comprehensive analyses, including SEM, FTIR, TGA, DSC, and DMA were conducted to evaluate the properties of the produced membranes. Gas permeability and ideal selectivity were measured at 25 degrees C and different pressures, ranging from 1 to 7 bar. Characterization results demonstrate that the glass transition temperature (Tg) of MMMs increased compared to pure Pebax (R) 1657, indicating that the addition of SSMMP/IL reduces the flexibility of the PEO chains, forming a rigid interface at the polymer/filler, which may enhance selectivity. This effect, corroborated by gas permeation, was observed for both CO2/N-2 and CO2/CH4. For CO2/N-2, the highest selectivity was achieved at lower filler concentrations, gradually decreasing as the filler load increased. MMM-0.5 wt% achieved the highest selectivity of 91.96. The membrane CO2 permeability rose with an elevated filler content, rising from 84.21 for pure Pebax (R) 1657 to 192.17 Barrer for MMM-20 wt% at 4 bar. The permeability results were influenced by the gas diffusion coefficients of the MMMs, which increased with increasing SSMMP/IL content. The effect of feed pressure on MMM-5 wt% was also assessed, revealing that CO2 permeability increased with increasing pressure, from 126.72 Barrer at 1 bar to 165.56 Barrer at 7 bar. This work showcased the viability of MMMs incorporating SSMMP/IL for industrial use, as they displayed separation capabilities that exceeded the 2008 Robeson upper bound.

The escalating emissions of CO2 into the atmosphere require the urgent development of technologies aimed at mitigating environmental impacts. Among these, aqueous amine solutions and polymeric membranes, such as cellulose acetate and polyimide are commercial technologies requiring improvement or substitution to enhance the economic and energetic efficiency of CO2 separation processes. Ionic liquids and poly(ionic liquids) (PILs) are candidates to replace conventional CO2 separation technologies. PILs are a class of materials capable of combining the favorable gas affinity exhibited by ionic liquids (ILs) with the processability inherent in polymeric materials. In this context, the synthesis of the IL GLYMIM[Cl] was performed, followed by ion exchange processes to achieve GLYMIM variants with diverse counter anions (NTf2−, PF6−, and BF4). Subsequently, PIL membranes were fabricated from these tailored ILs and subjected to characterization, employing techniques such as SEC, FTIR, DSC, TGA, DMA, FEG-SEM, and CO2 sorption analysis using the pressure decay method. Furthermore, permeability and ideal selectivity assessments of CO2/CH4 mixture were performed to derive the diffusion and solubility coefficients for both CO2 and CH4. PIL membranes exhibited adequate thermal and mechanical properties. The PIL-BF4 demonstrated CO2 sorption capacities of 33.5 mg CO2/g at 1 bar and 104.8 mg CO2/g at 10 bar. Furthermore, the PIL-BF4 membrane exhibited permeability and ideal (CO2/CH4) selectivity values of 41 barrer and 44, respectively, surpassing those of a commercial cellulose acetate membrane as reported in the existing literature. This study underscores the potential of PIL-based membranes as promising candidates for enhanced CO2 capture technologies.

The need to find alternative materials to replace aqueous amine solutions for the capture of CO2 in post-combustion technologies is pressing. This study assesses the CO2 sorption capacity and CO2/N2 selectivity of three dicationic ionic liquids with distinct anions immobilized in commercial mesoporous silica support (SBA- 15). The samples were characterized by UART-FTIR, NMR, Raman, FESEM, TEM, TGA, Magnetometry (VSM), BET and BJH. The highest CO2 sorption capacity and CO2/N2 selectivity were obtained for sample SBA@DIL_2FeCl4 [at 1 bar and 25 °C; 57.31 (±0.02) mg CO2/g; 12.27 (±0.72) mg CO2/g]. The results were compared to pristine SBA-15 and revealed a similar sorption capacity, indicating that the IL has no impact on the CO2 sorption capacity of silica. On the other hand, selectivity was improved by approximately 3.8 times, demonstrating the affinity of the ionic liquid for the CO2 molecule. The material underwent multiple sorption/desorption cycles and proved to be stable and a promising option for use in industrial CO2 capture processes.

Carbon dioxide (CO2) in the atmosphere of the Earth represents an abundant and largely free source of carbon, which remains heavily underestimated nowadays. The disbalance between the emission and utilization of CO2 puts the sustainable development of humanity at risk because of its possible correlation with global climate change. The valorization of CO2 is an important strategy to attend to the above-mentioned challenges. CO2 can be converted to dimethyl carbonate by grafting to methanol (CH3OH) in the presence of the catalyst. The presently known catalytic solutions require high temperatures and pressures to be employed. Herein, we report sodium fluoride as a new catalyst offering an unprecedentedly low activation barrier, 23 kJ/mol, for the carboxylation of CH3OH. The fluoride anion coordinates the hydroxyl hydrogen of CH3OH thanks to forming a very strong H-bond. Upon the collision with CO2, the proton detaches, and CO2 grafts to CH3O* while becoming the carboxyl group. The reaction finishes by methylating CH3OC(O)O- via the methyl radical originating from another CH3OH molecule (esterification stage). The hydrogen fluoride molecule is an intermediate in this reaction providing the proton and fostering esterification. The subsequent in-lab experiments showed that much milder conditions can be used to synthesize DMC out of CH3OH. Under 80 degrees C and 40 bar, we obtained an outstanding DMC yield of 21.1 %. However, the synthesis was also possible at lower temperatures giving DMC yields of 16.3 % at 65 degrees C, 14.7 % at 55 degrees C, and 10.8 % at 25 degrees C. The unprecedented possibility to obtain a non-negligible production of an organic carbonate at room temperature represents a cornerstone advance in the field of CO2 valorization and promises huge energy savings. Given the current global amount of the yearly prepared DMC amounting to over one million tons and the demand for this chemical by emerging chemical technologies, the achieved result is deemed to be of paramount importance. The exemplified catalytic mechanism is also interesting in the context of other syntheses, in which a low-energetic production of the methoxy moieties is a cornerstone.

Membrane-based CO2 separation is a promising technology compared to traditional processes, presenting advantages such as superior energy efficiency and reduced operational costs. This study investigates the enhancement of CO2/N-2 separation performance by incorporating ionic liquid [hmim][Tf2N] into polysulfone membranes. The membranes were produced with 5, 10, and 20 wt% IL, and their permeability was measured at 25 degrees C under pressures of 1 and 4 bar. Stability tests were also conducted. At 1 bar, the membrane with 20 wt% IL exhibited the highest CO2 permeability of 342.27 Barrer, while the membrane with 5 wt% IL demonstrated the best ideal selectivity for CO2/N-2 of 27.87. At 4 bar, the membrane with 5 wt% IL showed the highest ideal selectivity for CO2/N-2 of 40.81, with a CO2 permeability of 144.26 Barrer. Leaching tests indicated potential integrity loss in ionic liquid composite polymer membranes at high pressures. Specifically, the CO2 permeability of the PSF-[hmim] [Tf2N] 5 wt% membrane increased continuously post-testing due to IL leaching. However, the performance of the membranes remained stable at lower pressures (1 bar). These findings suggest that the produced membranes achieve higher permeability, CO2/N-2 selectivity, and CO2 diffusivity, making them suitable for post-combustion gas separation applications.

Mitigating the global warming caused by CO2 emissions from anthropogenic sources is a hot research topic in the current era. The high cost and difficulty in handling liquid solvent absorbents for CO2 capture are the main barriers to their industrial application. Earth-abundant solid sorbents are favorable candidates for CO2 separation, offering a low energy penalty for CO2 desorption. Here, Polysulfone (PSF) nanocomposites were prepared by simple solution blending. The carbon-based fillers, namely carbon nanotubes (CNT), and activated carbon (CA) in the range of 5-20 wt%, containing iron nanoparticles, were used as fillers. Their morphological, thermal, CO2 capture capacity and magnetic properties were comprehensively studied. Transmission electron microscopy (TEM) evidenced uniform filler distribution in the polymer matrix with sizes of 47-54 nm. Thermal analysis revealed an approximately 4 degrees C improvement in both the initial (Tonset) and maximum (Tmax) degradation temperatures by adding 5 wt% of nanoparticles compared to the pristine polymer. The glass transition temperature (Tg) of the pristine PSF and produced nanocomposites showed identical values as estimated by differential scanning calorimetry (DSC). The increase in filler amount gradually decreased the water contact angle values, indicating a hydrophilic classification of the PSF nanocomposites. The obtained PSF nanocomposites exhibited an efficient CO2 capture capacity of about 40-61 mgCO2/g at 45 degrees C, higher than pristine PSF. This remarkable achievement sets a new benchmark compared to previously developed systems. The introduction of the filler transforms the diamagnetic polymer matrix into a ferromagnet, presenting a coercivity of about 480 Oe, enhancing the material's potential for applications in microelectronics.

Encapsulated ionic liquids as green solvents for CO2 capture are reported in this work. We present a novel combination of water-based poly(ionic liquid) and imidazolium-based ionic liquids (Emim[X]). Poly(diallyldimethylammonium tetrafluoroborate)/Emim[X] capsules were developed for the first time using Nano Spray Dryer B-90. Capsules were characterized by FTIR, SEM/EDX, TEM, TGA, DSC, CO2 sorption, and CO2/N2 selectivity, CO2 sorption kinetic and recycling were also demonstrated. Comparing the capsules reported in this work, the combination of poly(diallyldimethylammonium tetrafluoroborate) and the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (P[DADMA]/BF4) showed great potential for CO2 capture and CO2/N2 separation, providing higher results (53.4 mg CO2/g; CO2/N2 selectivity: 4.58).

Water-based lubricants have been used in different industrial applications in recent years. However, studies evaluating the tribological and electrochemical effects of lubricants with Protic Ionic Liquid (PIL) and talc particles (TC) as additives on SAE 1010 and SAE 1045 steels are still scarce in the literature, which is the objective of this work. Samples extracted from steel sheets were investigated in the normalized (SAE 1010) and quenched-tempered (SAE 1045) conditions. Wear tests in a ball-on-plate type tribometer and corrosion tests using potentiondynamic polarization curves were performed in the presence of different lubricant solutions (PIL 3% + DI water, commercial lubricant 3% + DI water, with and without talc particle additions 0.05 and 0.1 wt%). Analyses of viscosity, pH, wettability, and particle size distribution were conduted on the lubricant and talc samples. Wear and corrosion surfaces were analyzed by SEM/EDS, and Raman techniques. The results showed that the tribofilm formed from the interaction between PIL lubricants and steel substrates decreased the wear due to the increase of lubricity of these lubricants. When the PIL and the commercial lubricants are compared, PIL additives presented higher performance, despite the talc addition. The influence of talc on the corrosion of steel is associated with the differential aeration effect, mitigated by adding the PIL.

Global warming linked to the industrial emissions of greenhouse gases may be the end of mankind unless it is adequately and timely handled. To prevent irreversible changes to the climate of the Earth, numerous research groups are striving to develop robust CO2 sorbents. Dialkyl carbonates (DACs) and CO2 exhibit obvious chemical similarities in their structure and properties. The degrees of oxidation of all atoms composing DACs and CO2 are identical resulting in very similar nucleophilicities and electrophilicities of all interaction centers. While both compounds possess relatively high partial atomic charges on their polar moieties, the molecular geometries prevent tight binding of the head groups. The computed DAC-DAC binding energies are ∼40 kJ mol-1, whereas the effect of the alkyl chain length is marginal. The phase transition points and shear viscosities of DACs are very low. We herein hypothesize and numerically rationalize that DACs represent noteworthy physical sorbents for CO2 thanks to the similar sorbent-CO2 and sorbent-sorbent interaction energies. By reporting in silico-derived sorption thermodynamics at various conditions, spectral and structural properties, and experimentally derived CO2 capacities and recyclabilities, we highlight the mutual affinity of DACs and CO2. Indeed, the experimentally determined CO2 sorption capacity of 0.88 mol% (diethyl carbonate) at 278.15 K and 30 bar is competitive. The unprecedentedly low DAC-CO2 binding energies, ∼14 kJ mol-1, suggest a low-cost desorption process and outstanding recyclability of the sorbent. We also note that DACs possessing long alkyl chains (butyl, hexyl, octyl) exhibit negligible volatilities, while preserving the liquid aggregate state over a practically important temperature range. The reported results may foster the development of a new class of CO2 scavengers with possibly quite peculiar characteristics.

The chemical transformation of carbon dioxide (CO2) into valuable chemicals is a fascinating way to reduce CO2 concentration in the atmosphere. Dimethyl carbonate (DMC) exhibits low toxicity, biodegradability, and versatile reactivity. DMC production by direct synthesis using CO2 and methanol (CH3OH) may be one of the ever most promising green routes. On the other hand, direct synthesis of DMC shows some drawbacks including unfavorable thermochemistry and quick deactivation of catalysts. The development of new catalytic systems currently represents an urgent agenda to overcome these disadvantages. This study investigates the catalytic activity of iron (Fe) and copper (Cu) catalysts supported on alumina (AL), silica (SI), and eggshells (ES) during the course of DMC production by direct synthesis. The supported catalysts were synthesized using the impregnation method and characterized by TGA, BET, DTP-NH3, XRD, and FESEM/EDS. The contents of the impregnated iron in the matrices are ES-Fe (13%) > AL-Fe (6%) > SI-Fe (4%). The contents of the impregnated copper are ES-Cu (7%) > AL-Cu (3%) = SI-Cu (3%). The DMC conversions equal 8.9 (AL-Cu), 6.2 (SI-Cu), 11.3% (ES-Cu), 6.1 (AL-Fe), 7.2 (SI-Fe), and 12.7% (ES-Fe). The ES-Fe recycle demonstrated stability of the catalytic action in the first and second reuse, maintaining high conversion and selectivity of DMC. All tests reveal a DMC selectivity of over 99%. The reported results suggest that the catalytic DMC production depends both on the nature of d-metal and support, whereas the ES-Fe system exhibits the best performance.

The objective of this work is to evaluate the wear and corrosion behaviours of different formulations of water-based lubricants containing protic ionic liquid (PIL) and bentonite particle additions. Carbon-steel samples were investigated in the normalized and quenched-tempered conditions. Wear tests and corrosion tests using potentiondynamic polarization curves were performed in the presence of different lubricant solutions (PIL 3 wt

In this study, we developed a one-step simplified suspension-based polymerization process for encapsuling ionic liquids (ILs) ([emim][TfO] and [emim][Tf2N]). Acrylic photoreactive monomers were cured using UV-365 light during the encapsulation process forming the capsule shell. The acetone extraction test confirmed IL encapsu-lation proving a high encapsulation efficiency for all samples (>80 %). For capsules produced with lower IL content, a homogeneous morphology was observed when compared to capsules with higher IL content. Sus-pension polymerization produced microcapsules presenting polynuclear morphology, as seen in TEM analysis. CO2 sorption ability and CO2/N2 selectivity of the produced capsules were superior when compared to pristine shell material. Capsule stability was proved by submitting the samples to several sorption/desorption cycles. [emim][TfO] microcapsules with low ILs concentration presented superior CO2 sorption results, 53 & PLUSMN; 0.9 mgCO2.g  1 (0.4 Mpa at 45 degrees C), and CO2/N2 selectivity, 4.5 & PLUSMN; 0.2, compared to [emim][Tf2N] microcapsules. The improvement in sorption capacity of [emim][TfO] microcapsules was greater than 50 % in comparison with the pristine shell material. Electronic structure modeling corroborated the experimental results proving that [emim] [TfO] is better to separate CO2/N2 thanks to three electron-rich oxygens. The sorption results allied to the easiness of the process represents a significant contribution to the scientific development of a new, efficient, and simplified method for the encapsulation of ionic liquids, which can be applied in the capture of CO2 in industrial exhaust gas streams.

Synthetic silico-metallic mineral particles (SSMMP) containing different amounts of Ni (SSMMP-Ni) and SSMMPNi functionalized with different IL (SSMMP-Ni-IL) were obtained and successfully used as solid adsorbents for CO2 sorption, CO2/N2 separation and highly recyclable heterogeneous catalysts active in the synthesis of different cyclic carbonates using CO2 as a starting reagent. Samples were characterized by infrared spectroscopy (FTIR), RAMAN spectroscopy, X-ray diffraction (XRD), thermal analysis (TGA), specific surface area measurements (BET) and scanning electron microscopy (SEM). Samples containing IL demonstrated high CO2 capture capacity (1.18-1.91 mmol CO2/g adsorbent - 1 bar CO2), CO2 selectivity (7.5-14.7) and stability. As catalysts, SSMMP-Ni 50% achieved a yield of 93.3% in propylene carbonate production (20 bar, 100 degrees C and 7 h) and constant yield up to 10 cycles. These materials are easy to synthesize, with low energy demand, high stability and versatile to be used as adsorbent in CO2 capture and catalyst for CO2 transformation.

The robust valorization of carbon dioxide (CO2) stays at the center of sustainable development. Since CO2 represents a low-energy compound, its transformation into commercially coveted products is cumbersome. In the present work, we report a revolutionary method to obtain dimethyl carbonate (DMC) out of methanol (CH3OH) and CO2 catalyzed by sodium chloride (NaCl) and similar inorganic salts. The computational exploration revealed a mechanism of favorable catalysis, which was subsequently confirmed experimentally. Unlike all competitive syntheses of DMC, the new one does not produce water and, therefore, the hydrolysis of a carbonate does not occur. No dehydrating agents are necessary. The employed catalyst is cheap and permanently exists in the same phase with the reactants and products. The action of NaCl was compared to those of other alkali metal salts, LiI, LiCl, and KI, and competitive performances were recorded. The experimentally obtained result outperforms most competing technologies according to the DMC yield, 19% with molecular sieves and 17% without molecular sieves. All existing competitors are excelled by the simplicity and cleanness of the synthesis. The reported advance substantially simplifies the synthesis of linear organic carbonates and robustly valorizes CO2.

The robust valorization of carbon dioxide (CO2) stays at the center of sustainable development. Since CO2 represents a low-energy compound, its transformation into commercially coveted products is cumbersome. In the present work, we report a revolutionary method to obtain dimethyl carbonate (DMC) out of methanol (CH3OH) and CO2 catalyzed by sodium chloride (NaCl) and similar inorganic salts. The computational exploration revealed a mechanism of favorable catalysis, which was subsequently confirmed experimentally. Unlike all competitive syntheses of DMC, the new one does not produce water and, therefore, the hydrolysis of a carbonate does not occur. No dehydrating agents are necessary. The employed catalyst is cheap and permanently exists in the same phase with the reactants and products. The action of NaCl was compared to those of other alkali metal salts, LiI, LiCl, and KI, and competitive performances were recorded. The experimentally obtained result outperforms most competing technologies according to the DMC yield, 19 and 17 simplicity and cleanness of the synthesis. The reported advance substantially simplifies the synthesis of linear organic carbonates and robustly valorizes CO2. Keywords: Dimethyl carbonate; carbon dioxide utilization; sodium chloride; methanol.

Membrane-based CO2 separation technology is a promising technology with low operating and energy costs and high scalability. This work describes the influence of synthetic silico-metallic mineral particles (SSMMP) and SSMMP/ionic liquids (IL) associated with polysulfone (PSF) to produce new mixed matrix membranes (MMM) for post-combustion technology. SSMMP is the precursor of synthetic talc undergoing no hydrothermal process resulting in a low-cost, energy-demanding, and CO2-free emission material due to its synthesis process. SSMMP have many reactive OH groups free on their surface making this material ideal to be compatibilized in a polymeric matrix. IL was immobilized in SSMMP to further improve CO2 affinity. As far as we know, this is the first time this material has been used to obtain MMMs. MMMs were prepared with concentrations of 0.5, 1, 2 and 3 wt % of fillers via melting solution and solvent evaporation. The obtained MMMs were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) with elemental mapping, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Permeability analyses were carried out at 25 degrees C and 0.4 MPa. The addition of pristine SSMMP and SSMMP/Im(nBu)Tf2N improved membrane selectivity decreasing the permeability for the majority of tested filler content. When using SSMMP/Im (nBu)I to obtain MMMs a different behavior was observed decreasing selectivity (except for MMM with 2% (w/ w) of filler) and increasing permeability in all studied concentrations. The best result was obtained for sample SSMMP/Im(nBu)Tf2N (2% w/w) achieving a selectivity of 71.9, four times higher than pristine polysulfone membrane.