Glycerol Blends Research Articles

Biocomposite Films of Amylose Reinforced with Polylactic Acid by Solvent Casting Method Using a Pickering Emulsion Approach

Binary and ternary blends of amylose (AM), polylactic acid (PLA), and glycerol were prepared using a Pickering emulsion approach. Various formulations of AM/PLA with low PLA contents ranging from 3% to 12% were mixed with AM matrix and reinforced with 25% cellulose nanofibers (CNF), and PLA-grafted cellulose nanofibers (g-CNF), the latter to enhance miscibility. Polymeric films were fabricated through solvent casting and characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Wide-Angle X-ray Scattering (WAXS), and the evaluations of physical, mechanical properties, and wettability were performed using contact angle measurements. The binary blends of AM and PLA produced films suitable for packaging, pharmaceutical, or biomedical applications with excellent water barrier properties. The ternary blends of AM/CNF/PLA and AM/g-CNF/PLA nanocomposite films demonstrated enhanced tensile strength and reduced water permeability compared to AM/PLA films. Adding g-CNF resulted in better homogeneity and increased relative crystallinity from 33% to 35% compared to unmodified CNF. The application of Pickering emulsion in creating AM-based CNF/ PLA composites resulted in a notable enhancement in tensile strength by 47%. This study presents an effective approach for producing biodegradable and reinforced PLA-based nanocomposite films, which show promise as bio-nanocomposite materials for food packaging applications.

The effects of feeding sows at onset of farrowing supplemental energy (blend of carbohydrates and glycerol) on farrowing kinetics and piglet vitality

Delivering piglets is one of the most energy-demanding activities sows undergo in their lifetime. Sows can have myometrial contractions from 2 to 12 h before the first piglet is expelled as well as a nest-building behavior. Thus, when the first piglet is delivered, the female has already used part of her energy supply. When the sow gets exhausted due to lack of energy, the farrowing process can be interrupted, causing damage to the viability and vitality of the piglets. In the present study, we evaluated the effects of feeding sows an energy supplement at the onset of farrowing on farrowing kinetics and piglet vitality. The energy supplement consisted of a blend of carbohydrates and glycerol which provides 439 kJ of metabolizable energy per kg of metabolic weight. A total of 180 sows were used. At the onset of farrowing, sows were assigned to one of the following treatments: sows that were not supplied energy at the onset of farrowing, serving as controls (CON, n = 85); sows fed the energy supplement at the onset of farrowing (ESP, n = 95). Farrowing kinetics, blood glucose concentration, and piglet vitality were recorded for each sow. Blood glucose concentration was assessed by puncturing the auricular vein and using a portable glucometer at four different time points: after the birth of the 1st piglet (T0), and at 20 (T20), 40 (T40), 80 (T80), and 180 (T180) min after the birth of the 1st piglet. The vitality of the 1st, 6th, 12th, 17th, and 20th piglet born was evaluated using the Apgar score. Piglet birth weight and average colostrum intake were measured. The farrowing duration was 20 min shorter (P < 0.05) for ESP sows in comparison with CON sows. Sows from ESP treatment had higher (P ≤ 0.05) blood glucose concentration at T20 and T40 compared to the CON sows. The inter-piglet birth interval was shortened (P < 0.05) by 14 min between the 1st and 2nd piglet for the ESP treatment. The 17th and 20th piglets born from ESP sows had higher (P < 0.05) Apgar score compared to piglets of the same birth order from CON sows. Colostrum intake was higher (P < 0.01) for piglets born from ESP sows. Litter growth performance did not differ (P > 0.05). In conclusion, feeding a blend of carbohydrates and glycerol as an energy supplement for farrowing sows improved farrowing kinetics and piglet vitality score.

Nanoporous hypercrosslinked polymers as cost-effective catalysts to significantly promote the CO2 absorption performance of water-lean solvents for post-combustion CO2 capture

In most cases, the slow CO2 sorption kinetics of water-lean solvents—which include low-volatile organic diluents—are the limiting factor when it comes to post-combustion CO2 capture. This study offers a solution by suggesting the use of catalysts based on nanoporous hypercrosslinked polymers (HCPs) to improve the removal efficiency of water-lean solvents based on diethanolamine (DEA) and to increase CO2 mass transfer. Simple and inexpensive monomers were used to prepare three HCPs: HCP-C, HCP-S, and HCP-B, which stand for benzene, polystyrene, and carbazole, respectively. Blends of DEA and Glycerol (Gly) were used to disperse these polymers. Addition of 0.5 wt% HCP to a solvent mixture of 20% DEA and 30% Gly considerably boosts removal efficiency and increases the amount of CO₂ that can be absorbed until the breakthrough point by as much as 3000%, according to the results. Additionally, various gas flow rates, DEA concentrations, and glycerol concentrations were also investigated to determine the HCP-C catalytic effect on the CO2 absorption. A volumetric overall mass transfer coefficient enhancement of up to 319 % is possible in the investigated ranges when using HCP-C, according to the findings. Moreover, a possible catalytic mechanism was suggested.

Synthesis of New Biodegradable Beauty Mask with Sodium Alginate and Agar

Nowadays, with the improvement of living standards, the consciousness of people over their skin status and hope for finding ways to pursue its perfect condition has become one of the most concerned topics. In this investigation, a wide range of sodium alginate, agar, and glycerol blends was rationed to find the most suitable mixture to produce beauty masks. The blend of 3 g pure sodium alginate, 1.25 g agar, and 250 mL of 4% (w/v) glycerol was used. The film without cross-linking could withstand twice as much weight compared to the film with CaCl2, making it 13 times higher when comparing its stress. The water content is higher for the film without CaCl2. When the two film was tested for glycerol and alcohol absorbance, sodium alginate with no cross-linking absorbance is preferred when testing in glycerol since it is less soluble. However, when testing with alcohol, the film with CaCl2 is less soluble, thus preferred. The above qualities in which the film sample with CaCl2 possess therefore enables it as a perfect paste for a beauty mask, being tensile, high absorbance of serum to provide a holistic care.

Glycerol as an Anti-Knock Additive and Secondary Fuel as a Substitute for Gasoline-Based Fuels for the IC Engine

The article discusses the possibility of using glycerol as an additive to the engine fuel in order to reduce the tendency of combustion knock, and thus to increase the octane number of a given fuel. Experimental tests were carried out on the UIT-85 research engine with a variable compression ratio from eight to eleven to test the intensity of the knock. The completely renewable fuel—the blend of glycerol with butanol in the ratio of 25 and 75%, respectively—was tested. A comparative analysis of the knock intensity was conducted with gasoline 95 and N-butanol tested as reference fuels. The developed method for knock analysis using the proposed knock indicator was also presented. The experimental results proved the proposed blend of N-butanol and glycerol reduces the knock intensity by more than 50% in the spark-ignition engine at a compression ratio of 10, maintaining engine performance at a similar level as it was for a gasoline-fueled engine. The results confirmed the thesis on the reduction of knock intensity when adding glycerol to N-butanol.

Development of novel dimethyl ether – Glycerol blends with improved viscosity and miscibility for potential compression-ignition engine application

Dimethyl Ether is a promising diesel alternative fuel due to its significantly low well-to-wheels greenhouse gas emissions from certain renewable pathways and soot-free combustion characteristic. However, in a compression-ignition engine, the fuel injection system exhibits decreased durability due to the dimethyl ether’s extremely low viscosity (i.e., 0.15 cSt @ 40 °C). In this study, the viscosity of dimethyl ether is improved to the level of No.2 diesel fuel (i.e., 1.9 cSt @ 40 °C) via glycerol blending. To prevent the phase separation between glycerol and dimethyl ether, effective co-solvents are determined based on different selection criteria: Hansen Solubility Parameter-based “averaged solubility distance”, viscosity, oxygen mass content, health and environmental impacts, and renewable production capability. As a result, propylene glycol and di-propylene glycol are selected as the final co-solvents and are used to form the two final dimethyl ether blends: i) Michigan DME blend I (i.e., dimethyl ether/dipropylene glycol/glycerol); and ii) Michigan DME blend II (i.e., dimethyl ether/propylene glycol/glycerol). The minimum mass ratio of co-solvent to glycerol to prevent the phase separation is measured to be 1.5 and 1.65 for Michigan DME blend I and II, respectively, at 40 wt% dimethyl ether content. The kinematic viscosity of the two final blends was successfully improved to the level of No. 2 diesel fuel at around 40–43 wt% dimethyl ether content, a higher dimethyl ether content than any previous blends reported. A preliminary engine demonstration result with one of the final dimethyl ether blends (i.e., Michigan DME blend I) is also briefly presented here with suggestions for future improvement. While the current article covers the blend development part of the current research, its companion article covers the life-cycle greenhouse gas emissions assessment for one of the final dimethyl ether blends (i.e., Michigan DME blend II).

Studies on the co-metabolism of glucose and glycerol in the fungus Umbelopsis isabellina

Over the past few years, it is observed an increased interest for oleaginous microorganisms in the perspective to produce microbial oils of great commercial interest through the consumption of low/zero cost substrates. In this paper, the physiology of the fungus Umbelopsis isabellina growing on blends of glycerol and glucose was investigated. In all experiments the fungus completely consumed glucose and produced satisfactory quantities of biomass containing reserve lipids in high percentages. However, glycerol concentration in the growth medium was negatively correlated to glucose assimilation rate, mainly during the balanced-growth phase. Nevertheless, at high initial concentrations, glycerol was partially consumed and seemed to contribute positively to the suppression of lipid degradation. Following the discovery of this complex regulatory mechanism regarding glucose and glycerol co-assimilation, the activity of three key-enzymes namely aldolase, glycerol kinase and glycerol dehydrogenase, which are implicated in glycerol and glucose assimilation, was investigated. The experiments revealed a clear preference of the fungus for glucose over glycerol. On the other hand, storage polysaccharides are degraded instead of storage lipid at the late oleaginous phase for maintenance purpose. These new biochemical features will enable the design of appropriate growth media for the co-fermentation of these two substrates by U. isabellina with the aim to maximize lipid accumulation.

Preparation of green film with improved physicochemical properties and enhanced antimicrobial activity using ingredients from cassava peel, bamboo leaf and rosemary leaf

Persistent petroleum based plastic polymers are posing a threat to the environment and human health. Hence, preparation of eco-friendly packaging materials from natural sources is innovative idea to replace persistent plastic films. However, biodegradable films from biomass absorb water that can promote bacterial growth and affect lifetime of film as well as the packed products. In this work, new biodegradable film with improved antimicrobial activity, physicochemical property and less water absorbing and holding property is prepared from modified blend of cassava peel starch (CPS), silica nanoparticle (SNP), glycerol plus rosemary essential oil (REO). The mixture (blend) of CPS, SNPs and glycerol in measured amount of distilled water was treated with acetic anhydride to reduce hydrophilic nature of the blend before adding REO. The content of SNPs in the biofilm was optimized by varying the concentration of SNPs (0.2–0.8%; w/w) keeping other factors constant. Based on the characterization results, the physicochemical property of the biofilms was dependent on the content of SNPs and the best result (film) has been found with 0.6% SNPs which was considered as optimum amount for further experiments. The film prepared from modified blend with 0.6% SNP had shown low water absorption, low water vapor transition rate, improved thermal stability, and less biodegradability. Based on the image from profilometer, the modified blend had shown better homogeneity with REO than unmodified blend and the film with REO had shown better antimicrobial activity as compared to the film without REO (control). The antimicrobial activity of the film with REO was also compared with reference (gentamicin) and its activity was comparable and promising. In general, the prepared film had shown improved physicochemical properties and enhanced antimicrobial activity.

Pulse electrodeposited zinc sulfide as an eco-friendly buffer layer for the cadmium-free thin-film solar cells

Zinc sulfide (ZnS) is an emerging alternate n-type buffer layer for the cadmium-free thin-film solar cells. The present research adopts a unique mixture of glycerol and tartaric acid for the emergence of phase-pure ZnS during pulse electrodeposition . Besides, proper optimization of pulse parameters aid in producing crystalline ZnS films with no post-deposition heat treatment. The as-deposited films exhibit cubic ZnS as confirmed from X-Ray Diffraction (XRD) and micro-Raman analyses. The optical study reveals an average transmittance of 71% in the wavelength spread of 300–900 nm with a band gap of 3.8 eV. The n-type semiconducting behavior of ZnS is affirmed from the Mott-Schottky analysis and the flat band potential is inferred to be −1.0 V vs SCE . The crystalline ZnS films produced from the economic pulse electrodeposition method devoid of heat treatment step, with their demonstration as photoanode in photoelectrochemical cells are suitable for the relevant applications. • A room temperature electrodeposition process for ZnS with better control over the morphology and composition. • Phase-pure ZnS is obtained using pulse electrodeposition with no post heat-treatment. • A novel method using a blend of organic reagents, tartaric acid and glycerol in the electrolyte.

Mass transfer coefficients of carbon dioxide in aqueous blends of monoethanolamine and glycerol using wetted-wall column

There is an urgent need for CO2 capture development because of the global warming crisis. Recently CO2 absorption by the mixture of monoethanolamine (MEA) and glycerol, as an eco-friendly solvent, has been considered due to its promising performance and low technical and environmental impacts. However, more aspects of this process, especially mass transfer coefficients, need to be studied further. In this work, a bench-scale wetted-wall column was used to find the CO2 mass transfer coefficients in the aqueous blends of MEA (25 wt%) and glycerol (5–20 wt%). The experiments were performed nearly to the industrial conditions of flue gas at atmospheric pressure and three different temperatures (313, 323, and 333 K). The gas flow rate was maintained around 0.17 ± 0.01 stdL/s, and the CO2 partial pressure was in the range of 1–15 kPa. The findings revealed that increasing the glycerol to 10 wt% improves the overall mass transfer (KG), and adding more glycerol up to 20 wt% decreases the KG. The gas-side mass transfer resistance (1/kg) found to be negligible. Thus, the primary mass transfer resistance was in the liquid phase. It is also found that the solution with 10 wt% glycerol and 25 wt% MEA (10G25M) had the highest liquid-side mass transfer coefficient (kg′) among the other solutions. The 10G25M showed a comparable and even better absorption rate than solutions with a higher concentration of MEA studied in the literature. Compared with industrial-grade, the kg′ of the 10G25M was over two times higher than the 30 wt% MEA solution.

Life-Cycle Greenhouse Gas Emissions Assessment of Novel Dimethyl Ether–Glycerol Blends for Compression-Ignition Engine Application

Life-Cycle Greenhouse Gas Emissions Assessment of Novel Dimethyl Ether–Glycerol Blends for Compression-Ignition Engine Application

Effects of Nopal Mucilage (Opuntia ficus-indica) as Plasticizer in the Fabrication of Laminated and Tubular Films of Extruded Acetylated Starches

Normal and acetylated rice and waxy maize starches with a blend of nopal mucilage (Opuntia ficus-indica) and glycerol were used for the preparation of laminated and tubular films by extrusion and blown extrusion, respectively. The composition of the formulation was 70% starch (normal or acetylated), 20% glycerol, and 10% nopal mucilage ( w / w ). The degrees of substitution (DS) for acetylated rice starch (0.94) and waxy maize starch (0.76) present high potential for use as a polymeric matrix in packing materials. The use of nopal mucilage can improve the processability of extruded and tubular films by favoring the increase of some mechanical and functional properties. The films elaborated with nopal mucilage and glycerol present a homogeneous relief without breaking, adhesiveness, and contraction once formed. The elongation values of acetylated waxy maize starch films (33%) were higher than those of rice acetylated films (17%), while the blown films presented a 30% decrease in tensile strength, compared to the laminated films. Acetylation generated more hydrophobic material for the rice starch sample, which can be evidenced by a decreased solubility of the laminated films. Films of both sources of acetylated starch showed a significant decrease in water vapor permeability and showed a plasticized starch disposition-type layer without unmelted starch granules.

Accelerating the separation of emulsified oil products using high electrostatic fields

To create an oil-based emulsified liquid, a blend of glycerol and biodiesel was stabilized with the aid of sodium oleate as an emulsifier. The time taken by the glycerol to settle down from the biodiesel under the sole effect of gravity has been compared to that attained under the influence of high electrostatic fields. Experiments were designed to study the effect of the employed electrode pairs, electrode distance, and voltage magnitude and polarity on the separation rate of glycerol. High DC voltage measurements and laser beam intensity readings were recorded every second via a computational micro-controller program. Results showed that the time taken to achieve 100% separation completeness under gravity reached 30,000 s (8.3 h). However, when an electrode pair was submerged to the proper height (4 cm apart) and the voltage was set to 2000 V, 99.02% separation completeness was reached within 1800 s (0.5 h). When the effect of the employed electrode pairs was studied, the obtained results revealed that the electrode pairs of different diameters gave the highest percentage of separation completeness and the shortest separation time at 4000 V. Gas chromatography (GC) analysis was performed to biodiesel samples before and after applying the high voltage. The results do not indicate the appearance of any foreign peaks, which confirms that the applied voltage has not create, or even initiate, any chemical reactions. Concerning the physical properties before and after applying the high voltage, insignificant changes has been measured in the density, refractive index, flash point, and water content.

Alginate-Edible Coatings for Application on Wild Andean Blueberries (Vaccinium meridionale Swartz): Effect of the Addition of Nanofibrils Isolated from Cocoa By-Products.

Edible coatings and films are appealing strategies for the postharvest management of blueberries. In the current work, alginate and alginate/cellulose nanofibril (CNF) edible coatings crosslinked with calcium chloride were developed for application on Andean blueberry (a promissory wild blueberry). Cocoa by-products were valorized through the isolation of their CNFs, and these were incorporated in the edible coatings. Edible coating formulations were based on blends of alginate (2% w/v), CNFs (0%, 0.1%, or 0.3%), glycerol, and water. In addition, stand-alone films were prepared, and their light and water vapor barrier properties were studied before applying the coating on the fruit surface. The results show that the addition of CNFs caused a significant decrease in the transparency and the water vapor permeability of the alginate films. After applying on the Andean blueberry fruits, the alginate and alginate/CNF coatings enhanced the appearance and the firmness of the fruits. Moreover, they significantly reduced the respiration rate and the water loss of the Andean blueberries throughout the 21 days of refrigerated storage. Alginate and alginate/CNFs coatings may be considered a useful alternative for the delay of the postharvest deterioration of Andean blueberries.

An insight into molecular motions and phase composition of gliadin/glutenin glycerol blends studied by13C solid‐state and1H time‐domain NMR

ABSTRACTMonitoring of the molecular motions and secondary structures of gliadin (Gli) and glutenin (Glu) in blends with 10, 20, 30, and 40% glycerol was performed by solid‐state (SS) and time domain (TD) NMR spectroscopy. Increasing the glycerol content increased the relative amount of β‐sheets and disordered structures, while decreasing α‐helices in Gli/Glu–glycerol blends studied by13C CPMAS NMR. For ≥20% glycerol samples, the protein side‐chain mobility increased similarly for Gli and Glu. A higher proportion of α‐helices versus β‐sheets was found in Gli‐glycerol blends compared with Glu–glycerol blends. Glycerol acted as “immobilized” in 10–20% glycerol Gli samples and was found mainly “free” in 30 and 40% glycerol Gli/Glu samples. During temperature experiments, 30 and 40% glycerol amounts impacted the dynamic molecular behavior of the Gli and Glu proteins differently than lipids, as observed by TD‐NMR. The combination of TD‐NMR together with SS‐NMR showed details of the dynamic molecular variations in Gli/Glu protein structure and are promising techniques to monitor the molecular dynamics of plasticized proteins. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys.2018,56, 739–750

The use of glycerol and cooking oil in masonry unit production

This paper presents an investigation into the development of a novel glycerol-bound masonry unit and the use of a multi-parameter mathematical modelling technique in evaluating the possibility to reduce the amount of sample produced with a comparable result obtained. Initially, an experimental optimisation was carried out to identify the best performance sample in term of compressive strength. The binder used for this stage is the blend of clean cooking oil and pure glycerol incorporating with secondary aggregates include incinerator bottom ash and pulverised fuel ash. Additional samples were made using natural aggregates and waste binders (waste cooking oil and waste glycerol) to evaluate their performance in relation to masonry products found in the UK in terms of compressive strength and water absorption properties. These properties are good indicators of overall performance of masonry units. In addition, modelling techniques were also used to evaluate the laboratory testing strategy to suggest the reduction in number of samples being produced in future experimental studies. Results from the study demonstrated that the novel masonry units could be produced with properties that were at least equivalent to those of currently used in the UK and modelling technique could reduce up to 90% of sample for the problem with three parameters.

Cogasification of Crude Glycerol and Black Liquor Blends: Char Morphology and Gasification Kinetics

AbstractIn this study, we assessed the feasibility of black liquor/glycerol blends as a potential gasification feedstock. The char gasification reactivity and kinetics were studied at T=750, 800, 850, and 900 °C for 20 and 40 % blends of glycerol with black liquor. Three qualities of glycerol were used including two industrial‐grade crude glycerols. The gasification rates were similar for all blends; therefore, the alkali‐metal catalysis is also sufficient for the char blends (alkali/C atomic ratio between 0.45 and 0.55). The blends with the most impure glycerol (containing K) had the lowest activation energies (∼120 kJ mol−1) and reaction times for char gasification and, therefore, had fuel properties suitable for gasification. The char particles from different blends showed surface morphologies similar to those of black liquor chars with an even surface distribution of alkali elements. A loss of alkali (mainly K) from the fuel blends during pyrolysis indicated the necessity to perform gas‐phase studies of alkali release. Overall, these results encourage the use of glycerol as a potential gasification feedstock for catalytic‐gasification‐based biorefineries.

Simulation of Aqueous Blend of Monoethanolamine and Glycerol for Carbon Dioxide Capture from Flue Gas

This study investigated CO2 capture from flue gas by using glycerol as solvent. Absorption was simulated using a rate-based model with three cases under similar operating conditions. CO2 separation was first simulated using ENRTL-RK thermodynamic model with monoethanolamine (MEA) as solvent. CO2 absorption was then simulated using NRTL-RK thermodynamic model with glycerol solvent, and then an aqueous mixture of MEA/glycerol was also simulated using ENRTL-RK thermodynamic model. Simulation results confirm that glycerol can be used as promoter with MEA solvent to enhance CO2 capture. The optimal glycerol concentration for CO2 absorption is 10–40 wt %, in which 10 wt % glycerol exhibits the lowest CO2 concentration in the outlet gas from the absorber. The CO2 removal efficiency increases from 62.24% for 10 wt % MEA aqueous solution to 64.33% for the mixture of 10 wt % MEA–10 wt % glycerol aqueous solution. The CO2 removal efficiency for 10 wt % glycerol aqueous solution is 27.31%.

Co-utilization of corn stover hydrolysates and biodiesel-derived glycerol by Cryptococcus curvatus for lipid production

In the present study, synergistic effects were observed when glycerol was co-fermented with glucose and xylose for lipid production by the oleaginous yeast Cryptococcus curvatus. Glycerol was assimilated simultaneously with sugars at the beginning of the culture without adaption time. Furthermore, better lipid production results, i.e., lipid yield and lipid productivity of 18.0g/100g and 0.13g/L/h, respectively, were achieved when cells were cultured in blends of corn stover hydrolysates and biodiesel-derived glycerol than those in the hydrolysates alone. The lipid samples had fatty acid compositional profiles similar to those of vegetable oils, suggesting their potential for biodiesel production. This co-utilization strategy provides an extremely simple solution to advance lipid production from both lignocelluloses and biodiesel-derived glycerol in one step.

Experimental investigation of the combustion of crude glycerol droplets

The objectives of the work are, first, to determine the combustion characteristics of crude glycerol, a by-product of the synthesis of biodiesel and, second, to systematically investigate the relationship between the behaviors observed and the presence of different components. With that purpose, the combustion of droplets of crude glycerol was studied in a drop tube facility and compared with different blends of pure glycerol with water, alcohol and salts. The evolution of drop size was determined from pictures recorded with a CCD camera and a long distance microscope. After injection, the droplet size initially remains about constant (initial liquid heating) and then decreases depicting a curve in good agreement with the d2-law. At some distance from injection, the droplets were shattered due to microexplosions, producing in most cases small fragments. The combustion curves for crude glycerol were compared with those for pure glycerol and its blends with water, alcohols and salts. Pure glycerol droplets displayed a combustion rate practically identical to that of crude glycerol, but did not experience microexplosions. These phenomena could be due to the presence of water or alcohols, with much lower boiling temperatures, but the experiments performed for a wide range of blends of pure glycerol with water, ethanol and/or methanol did not exhibit any kind of disruptive behavior. Additional tests performed with blends of pure glycerol containing alkali salts consistently showed the occurrence of microexplosions, even when the salt was dissolved in pure glycerol without adding any water or alcohol. It was then concluded that the microexplosions observed for crude glycerol droplets were actually induced by the decomposition of alkali salts, and not to the explosive evaporation of water or alcohols as initially expected.