Glycerol Carbonate Research Articles

Glycerol Carbonate as an Emulsifier for Light Crude Oil: Synthesis, Characterization, and Stability Analysis

This study focuses on the synthesis and application of glycerol carbonate (GC) as an emulsifier for light crude oil. GC was synthesized from glycerol and dimethyl carbonate via transesterification, achieving a 90% yield. Characterization through 1H-NMR, 13C-NMR, and FT-IR confirmed its structure. The emulsification properties of GC were tested by mixing it with light crude oil and water, demonstrating effective emulsification and forming stable emulsions. Stability tests with GC concentrations of 60/40, 70/30, and 80/20 revealed that emulsions remained stable for over 24 h. A particle size analysis indicated that higher GC concentrations produced smaller droplet sizes, enhancing the emulsification efficiency. This study highlights the potential applications of GC in oil spill remediation and enhanced oil recovery, emphasizing its biodegradability and low toxicity as environmental benefits. Overall, GC is presented as an effective and eco-friendly emulsifier for light crude oil, offering stable emulsions and promising industrial applications.

Glycerol Carbonate Production via Transesterification: The Effect of Support Porosity and Catalyst Basicity

Glycerol transesterification with diethyl carbonate (DEC) using catalysts with different porosities as support for CaO was performed, seeking the evaluation of how textural properties influence glycerol conversion and product selectivity. A total of 20% CaO was supported on ZSM-5, K-10, MCM-41, SiO2, and γ-Al2O3. Catalysts showed a well-dispersed active phase of CaO in all the supports and no changes in the support crystalline structure were noticed. Reactions were performed in dimethyl sulfoxide (DMSO), 10 wt.% of catalyst in relation to glycerol, at 130 °C, and 1:3 glycerol/DEC molar ratio. According to our results, the higher the pore volume and pore size, the higher the glycerol conversion. On the other hand, concerning selectivity, higher glycerol carbonate selectivities were reached when strong basic sites were present. A total of 86% glycerol conversion and 91% glycerol carbonate selectivity were found using 60% CaO supported on γ-Al2O3 after 5 h of reaction.

Harnessing Mg–Zn–Ce Ternary Mixed Oxide Nanostructure-Based Catalysts for Efficient Carbonylation of Glycerol with CO2 to Glycerol Carbonate

Harnessing Mg–Zn–Ce Ternary Mixed Oxide Nanostructure-Based Catalysts for Efficient Carbonylation of Glycerol with CO₂ to Glycerol Carbonate

Mild one-pot production of glycerol carbonate from CO2 with separation from ionic liquid catalyst

Carbon capture and utilization stands as way forward in the minimization of CO2 emissions. It complements the search for clean and effective energy, as it is challenging to achieve zero to negative CO2 net emissions. The glycerol carbonate product opens a new strategy based on a double-residue approach (glycerol and CO2) to contribute, together with ionic liquids (ILs), drafting a new one-pot concept (intensified three phase reactor) at mild conditions and using homogeneous catalysts. In this work, the catalytic activity of [P666,14][Br] in the cycloaddition of CO2 to glycidol has been demonstrated to be highly effective under mild conditions of 45 °C and 5 bar. In addition, liquid–liquid extraction approach is found to be an efficient separation strategy for carbonate product and IL catalyst. 1-Decanol (DOH) is selected as efficient extracting solvent, due to its almost complete immiscibility with glycerol carbonate, as well as the high distribution ratio of the IL catalyst in DOH rich phase. It implies an easy product separation and, simultaneously, an easy catalyst recovery. A preliminary kinetic validation of the three-phase reactor performance has been properly described, enabling the intensified concept. Finally, combining COSMO/Aspen simulation and life cycle assessment (LCA) methodologies, low energy consumption (avoiding heating) and low GWP scenarios for the CO2 conversion process have been concluded. This work enables a new concept together with concluding the path to developing this CCU technology in the search of zero to negative CO2 emissions to sustainably capture and convert CO2 into value-added products.

Valorization of Glycerol to Glycerol Carbonate and Glycidol by Different Dialkyl Carbonates Utilizing Tricalcium Aluminate Hexahydrate as Transesterification Catalyst

AbstractIn this study, we report a base‐catalyzed transesterification reaction of glycerol, a waste product of the biodiesel industry, with various dialkyl carbonates, which act both as reactants and solvents, to convert glycerol carbonate into an industrially useful molecular building block. The catalyst, being used for the first time, is also a waste product from industry, present in bauxite residues and in the Portland cement, simply known as tricalcium aluminate. Despite being well‐known and readily available, this solid is only extremely poorly researched catalyst, nevertheless, using dimethyl and diethyl carbonate, glycerol conversion rates >80% and glycerol carbonate yields >60% could be achieved in just 1 h (under air atmosphere and reflux). In a comparison of the performance with other catalysts commonly researched today, as well as with other components of red mud and cements, the results showed that tricalcium aluminate is excellent, cheap, and largely environmentally friendly material for this purpose. Reusability studies of the catalysts have also shown that they provide high conversion and product yields even after repeated use, although different material characterization techniques showed intense glycerol‐catalyst surface interaction and intermediate product formation, the deactivating side effects of which could be avoided by catalyst regeneration steps.

Confinement of Ultrasmall Pd Clusters Within Nanosized ZIF-8-Derived Cu-N-C Materials for Efficient and Stable Synthesis of Glycerol Carbonate from Glycerol

Confinement of Ultrasmall Pd Clusters Within Nanosized ZIF-8-Derived Cu-N-C Materials for Efficient and Stable Synthesis of Glycerol Carbonate from Glycerol

Crystallization kinetics as a tool to fine-tune the catalytic activity of Na-LTA zeolite precursors in the transesterification of glycerol to glycerol carbonate

Glycerol carbonate is a versatile molecule used as a fuel additive and a chemical building block. It is a prominent route for glycerol valorization, improving the biodiesel production chain. This base-catalyzed reaction can be carried out using sodium-type zeolites if accessibility to the basic sites is ensured. Herein, we report a facile strategy to fine-tune the number and access to basic sites of Na-LTA zeolite precursors via monitoring the crystallization kinetics of the microporous material. It is demonstrated that an optimal glycerol to glycerol carbonate conversion is obtained when using the solid obtained at the beginning of the crystallization (90 min at 100 °C of hydrothermal step). Textural and spectroscopy characterization reveals that semicrystalline material presents many basic aluminate anions in a very open structure, allowing facile access to glycerol and propylene carbonate. Moreover, it is shown that this catalyst is stable in four successive reaction cycles and active in different reactions conditions

Glycerol Carbonate and Solketal Carbonate as Circular Economy Bricks for Supercapacitors and Potassium Batteries.

Considering the worldwide market of batteries and supercapacitors, the (partial or total) replacement of conventional fossil-derived carbonates with bio-based ones in electrolyte formulations would allow the production of safer and more sustainable devices. In this work, embracing the 7th principle of green chemistry, glycerol derivatives (namely glycerol carbonate and solketal carbonate) are tested as solvents and additives for electrolyte formulations. Glycerol carbonate is innovatively employed as promising electrolyte solvent for electric double-layer capacitors with excellent performances. On the other hand, a solketal carbonate-laden liquid electrolyte is investigated for potassium-based batteries, showing a rather stable electrochemical behaviour and performance close to those of commercial oil-derived alternatives.

Application of KF/waste glass catalyst in the synthesis of fatty acid esters under pressurized conditions without glycerol generation

In this study, the efficiency of applying the KF/waste glass catalyst was tested in the transesterification of crambe oil under pressurized conditions for the synthesis of esters and glycerol carbonate (GLC). For this, a miscella pressurized extraction was used. The influence of temperature on different residence times was evaluated, and to verify the effect of the catalyst on the process, non-catalytic reactions were conducted. In reactions without the use of catalyst, a temperature of 250 °C was required to obtain >90 % esters yield. In the catalytic reactions, the operating conditions were reduced to 225 °C, to obtain ∼96 % esters yield, also providing the synthesis of a greater quantity of GLC, and a glycerol-free sample. The wet modification of powdered glass waste with KF results in the K2SiF6, NaF, CaF2, and KCaF3 phases. The laser-induced breakdown spectroscopy analyses showed the presence of fluorinated compounds in the catalyst. Furthermore, calcium and sodium ions from the glass waste matrix support were the source for the crystalization of K2SiF6/CaF2/KCaF3 and NaF phases, respectively. The catalyst showed a good catalytic activity, promoting high ester and GLC formation at 225 °C, 10 min and 10 MPa, remaining with good performance even after 8h of reaction, but it is important to mention that the stability of the catalyst needs to be improved due to the leaching of K to Ca.

Transformation of by-product silicon tetrachloride to an efficient and stable heterogeneous base catalyst: Valorization of glycerol into valuable glycerol carbonate

The by-product silicon tetrachloride (SiCl4) from the polysilicon industry was recycled to fabricate a highly efficient and stable lithium silicate (LS) catalyst for upgrading of oversupplied biodiesel by-product glycerol to valuable glycerol carbonate (GC). The characteristics of the LS catalyst were systematically investigated by various experimental characterization techniques and density functional theory (DFT) calculations. The experimental results showed that the hydrolysis of SiCl4 in the lithium nitrate solution helping to the solid phase synthesis of the LS catalyst as lithium could be uniformly dispersed in the silica gel. The as-synthesized LS catalyst mainly consists of lithium orthosilicate with strong basic sties, favoring the catalytic conversion of glycerol. The LS catalyst exhibited an appreciably high catalytic efficiency (turnover frequency of 2.72 min−1) and glycerol conversion (99.8±1.8 %) compared to other reported solid base catalysts. The apparent activation energy (Ea) of this reaction was calculated to be 39.51 kJ/mol. Further, benefiting from the stable silicate structure, the LS catalyst showed an enhanced catalytic stability as the glycerol conversion declined less than 5 % after five times reuse without regeneration. The LS catalyst also revealed marked resistance to the solid base catalyst poisons like water and methanol compare to that of commercial calcium-based catalyst. The temperature-programmed desorption of CO2 (CO2-TPD) and DFT results affirmed that the low-coordination lattice oxygen of the isolated SiO4 tetrahedron on the surface of the LS catalyst acting as a strong basic electron donor promoted the transesterification reaction between DMC and glycerol. As a result, the SiCl4-derived LS catalyst possessed remarkable catalytic efficiency and reusability, which could be an ideal candidate to meet the requirements for industrial application and highlight the potential application of the by-product SiCl4.

The Catalytic Coupling of CO2 and Glycidol toward Glycerol Carbonate

The Catalytic Coupling of CO₂ and Glycidol toward Glycerol Carbonate

Understanding the reaction dynamics of glycerol conversion into glycerol carbonate by transesterification of carbonic acid esters over CaO

The conversion of glycerol into value-added products is crucial for reducing waste generation in the biodiesel industry. In this context, glycerol carbonate has emerged as a promising molecule, capable of being produced through various processes, with glycerol transesterification being considered the most environmentally friendly method. In order to investigate the transesterification process comprehensively, this work focused on reactions between glycerol and different carbonic acid esters (dimethyl carbonate, diethyl carbonate, ethylene carbonate, and propylene carbonate), utilizing calcium oxide (CaO) as a basic catalyst. The catalyst was obtained commercially and characterized by X-ray diffraction (XRD), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The catalyst characterizations showed that it consisted of nano and micrometric particles with high purity, making it suitable for use without prior pretreatment. The reactions were conducted in a batch reactor using dimethylformamide as a solvent, and the products were analyzed by gas chromatography (GC-FID and GC-MS). Experiments were performed to investigate the effects of different reaction parameters on the formation process of glycerol carbonate and potential co-products. CaO showed moderate catalytic activity in glycerol conversion, which occurred in three steps, forming glycerol carbonate with high selectivity, along with small amounts of co-products, glycidol and glycerol tricarbonate. Thus, considering the results obtained in this and other studies, it was possible to identify that moderately strong basic catalysts favor simple reaction mechanisms, predominantly yielding glycerol carbonate. Conversely, highly basic catalysts induce more complex reaction mechanisms, resulting in significant formation of co-products.

Engineering Lewis-Acid Defects on ZnO Quantum Dots by Trace Transition-Metal Single Atoms for High Glycerol-to-Glycerol Carbonate Conversion.

Efficient conversion of biomass wastes into valuable chemicals has been regarded as a sustainable approach for green and circular economy. Herein, a highly efficient catalytic conversion of glycerol (Gly) into glycerol carbonate (GlyC) by carbonylation with the commercially available urea is presented using low-cost transition metal single atoms supported on zinc oxide quantum dots (M1-ZnO QDs) as a catalyst without using any solvent. A facile one-step wet chemical synthesis allows various types of metal single atoms to simultaneously dope and introduce Lewis-acid defects in the ZnO QD structure. It is found that doping with a trace amount of isolated metal atoms greatly boosts the catalytic activity with Gly conversion of 90.7%, GlyC selectivity of 100.0%, and GlyC yield of 90.6%. Congruential results from both Density Functional Theory (DFT)and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (in situ DRIFTS) studies reveal that the superior catalytic performance can be attributed to the enriched Lewis acid sites that endow optimal adsorption, formation of the intermediate for coupling between urea and Gly, and desorption of GlyC. Moreover, the tiny size of ZnO QDs efficiently promotes the accessibility of these active sites to the reactants.

Metal-organic framework-derived base catalyst for conversion of dimethyl carbonate to glycerol carbonate

Glycerol carbonate (GLC) offers a range of benefits including biodegradability, versatility, and its potential for carbon capture and utilization. Base catalysts play a crucial role for GLC synthesis by facilitating the activation of reactants, enhancing nucleophilicity, accelerating reaction kinetics, and enabling catalyst regeneration. In this study, metal–organic framework (MOF) derived hybrid structure, CaO-MgO@Al2O3, was developed as a base catalyst to promote transesterification of glycerol with dimethyl carbonate (DMC) to form GLC. The results show that hydrothermal plus wet-impregnation routes formed the hybrid nanostructure with homogenously dispersed Ca, Mg and Al elements. Further, the synthesized catalysts showed significantly high specific surface area and basicity (2.656 mmol g−1). High selectivity (>99 %) and high GLC yield (96.2 %; 208.9 mmol g-cat−1) were achievable. This study demonstrated the rational design concept of MOF-derived hybrid structures used in the enhancement of base catalysis for transesterification of DMC to GLC, offering an effective solution with mild reaction conditions and high conversion.

Can Glycerol Carbonate be Synthesized Without a Catalyst?

Abstract: Biodiesel and oleo-chemical industries have been producing huge quantities of glycerol as a by-product. Value-added products can be synthesized from glycerol through different chemical and enzymatic reactions, such as oxidation, carbonylation, reforming, acetalyzation, etherification, dehydration, hydrogenolysis, hydrolysis, esterification, and transesterification. Glycerol is a low-cost polyol that can be converted into glycerol carbonate, which has potential applications in polymer and biobased non-isocyanate polyurethanes industries (Bio-NIPUs). The present contribution is the first of its kind to report on the synthesis of glycerol carbonate via catalyst and solvent-free transesterification of glycerol with dimethyl carbonate under conventional as well as microwave heating. Additionally, a comparative study of conventional and microwave-assisted transesterification was performed. Under conventional heating, 78% glycerol carbonate is obtained at 120oC in 36 hours, whereas, using microwaves, 92% of glycerol carbonate can be achieved in 30 minutes. Presently, biomass-based heterogeneous materials are used in catalysis due to their importance within the context of sustainability. In line with this, in this work, a series of green catalysts, namely, molecular sieves (MS, 4Å), Hβ- Zeolite, Montmorillonite K-10 clay, activated carbon prepared from the shell of groundnut (Arachis hypogaea), and biochar from sawdust pyrolysis were successfully employed. Glycerol carbonate was thoroughly characterized by 1H and 13C NMR, FT-IR and MS. The method described here is facile and green since the utilization of bioresource (glycerol) for the production of glycerol carbonate is performed under microwave.

Resourcification of CO2 to high-value-added glycerol carbonate by ZnAlCe composite oxides with frustrated Lewis pairs

Zinc-aluminum-cerium composite oxide (ZnAlCe) catalysts were prepared by co-precipitation to catalyze the direct synthesis of glycerol carbonate (GC) from carbon dioxide (CO2) and glycerol. The characterization results showed that the lattice oxygen served as Lewis basic centers and Ce4+ served as Lewis acidic centers on Zn4AlCe catalyst, and frustrated Lewis pairs (FLPs) were formed due to the steric hindrance in the catalyst structure. CO2 was easily activated by FLPs because the acidic and basic centers of FLPs bound to the oxygen and carbon atoms of CO2, respectively. The experimental results indicated that Zn4AlCe catalyst presented excellent catalytic performance with good thermal stability and strong regeneration ability. Under the reaction conditions of 0.115 g catalyst, 12 h, 170 °C, 4.5 MPaCO2 and 5 mL acetonitrile dosage, the GC yield and selectivity were 28.9 % and 51.0 %, respectively. The GC yield is relatively high among similar catalysts reported so far, which lays the foundation for future industrial considerations.

Scalable Synthesis of Glycerol Carbonate Using Serially Connected Mesofluidic-Plate Reactors

Scalable Synthesis of Glycerol Carbonate Using Serially Connected Mesofluidic-Plate Reactors

Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO2 into glycerol carbonate

Glycerol carbonate, an important glycerol value-added product, has been widely used as the active intermediates and inert solvents in the synthesis of cosmetics, detergents, chemical intermediates, polymers, and so on. The direct carbonylation from glycerol with CO2 is considered as a promising route, but still a tough work due to the thermodynamic stability and the kinetic inertness of CO2. In this work, highly-selective direct carbonylation of glycerol and CO2 into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides (MgInCe-MMO), which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides (MgInCe-LDHs). By precisely modulating the surface basic-acidic properties and the oxygen vacancies, an efficient carbonylation of glycerol with CO2 has been achieved with a selectivity of up to > 99% to glycerol carbonate. Deep investigation on the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified.

Active-site engineering of a frustrated-Lewis-pair Au-loaded Zn-Al catalyst for the highly stable synthesis of glycerol carbonate from co-utilisation of CO2 and glycerol

Solid frustrated-Lewis-pair catalysts, based on Zn-Al composite oxide modified loaded with Au (Aux/ZnAl-CHT), were prepared by calcination of hydrotalcite precursors and tested for the direct synthesis of glycerol carbonate using CO2 as the carbon source. An Au5/ZnAl-CHT catalyst shows the highest catalytic performance with the glycerol carbonate yield of 19.5 % and the selectivity of 50.5 % at 170 °C and 4.0 MPa CO2, while maintaining good thermal stability and excellent regeneration ability. A series of characterization results and density functional theory (DFT) calculations indicated the introduction of Au leads to more frustrated-Lewis-pairs in Zn-Al composite oxide (ZnAl-CHT), which improve the adsorption and activation of CO2. Meanwhile, FTIR analysis indicates that glycerol is activated by Zn2+ for the formation of zinc glycerolate intermediates. The above dual synergistic activation processes effectively enhance the catalytic performance. And the reaction pathway is proposed for the synthesis of glycerol carbonate from CO2 and glycerol.

A Promising Compound for Green Multiresponsive Materials Based on Acyl Carrier Protein.

A gel that exhibits intrinsically multiple-responsive behavior was prepared from an oligopeptide and studied. ACP(65-74) is an active decapeptide fragment of acyl carrier protein. We investigated 3% w/v ACP(65-74)-NH2 self-healing physical gels in water, glycerol carbonate (GC), and their mixtures. The morphology was investigated by optical, birefringence, and confocal laser scanning microscopy, circular dichroism, Fourier transform infrared, and fluorescence spectroscopy experiments. We found that all samples possess pH responsiveness with fully reversible sol-to-gel transitions. The rheological properties depend on the temperature and solvent composition. The temperature dependence of the gels in water shows a peculiar behavior that is similar to that of thermoresponsive polymer solutions. The results reveal the presence of several β-sheet structures and amyloid aggregates, offering valuable insights into the fibrillation mechanism of amyloids in different solvent media.