Triacetin Research Articles

Ultrasound-Assisted Preparation of Hyaluronic Acid-Based Nanocapsules with an Oil Core.

Liquid-core nanocapsules (NCs) coated with amphiphilic hyaluronic acid (AmHA) have been proposed for the preparation of drug and food formulations. Herein, we focused on the use of ultrasound techniques to (i) optimize the polysaccharide chain length with respect to the properties of NCs stabilized with AmHAs and (ii) form oil-core nanocapsules with a coating composed of AmHAs. The results indicate that sonication is a convenient and effective method that allows for a controlled reduction in HA molecular weight. The initial (H-HA) and degraded (L-HA) polysaccharides were then reacted with dodecylamine to obtain hydrophobic HA derivatives (HA-C12s). Then, NCs were prepared based on HA-C12s using ultrasound-assisted emulsification of glyceryl triacetate oil. The nanocapsules coated with L-HA-C12 showed greater stability compared to the longer-chain polysaccharide. Molecular dynamics (MD) simulations revealed that HA-C12 readily adsorbs at the water-oil interphase, adopting a more compact conformation compared to that in the aqueous phase. The dodecyl groups are immersed in the oil droplet, while the main polysaccharide chain remaining in the aqueous phase forms hydrogen bonds or water bridges with the polar part of the triglycerides, thus increasing the stability of the NC. Our research underscores the usefulness of ultrasound technology in preparing suitable formulations of bioactive substances.

Molecular dynamics study on the physical compatibility of SEBS/plasticizer blend systems.

Thermoplastic elastomer styrene-ethylene-butylene-styrene block copolymer (SEBS) has excellent mechanical properties and aging resistance, so it has good application prospects in thermoplastic solid propellants. The selection of plasticizer is one of the keys to the formulation design of thermoplastic solid propellant. The compatibility of the plasticizer with the polymer determines the plasticizer's ability to plasticize the polymer's molecular chain segments. Herein, the compatibility of four plasticizers with SEBS was investigated, and the results declared that the order of compatibility between SEBS and the four plasticizers is SEBS/WO > SEBS/DOS > SEBS/DEP > SEBS/TA. Physical compatibility of SEBS binder with plasticizer triacetin (TA), diethyl phthalate (DEP), dioctyl sebacate (DOS), and 26# industrial white oil (WO) was simulated using molecular dynamics (MD) method via Materials Studio 8.0, and the simulation results were verified experimentally. The results showed that the compatibility of SEBS with these plasticizers can be comprehensively evaluated by analyzing solubility parameters, radial distribution functions, and blend miscibility simulations.

Effect of DMSO and Triacetin Solvents on Polyvinylidene Fluoride Polymorphs: Molecular Dynamics Simulations

In this article, molecular dynamics simulations are performed to investigate the interaction between polyvinylidene fluoride (PVDF) polymorphs (β phase has more properties compared with α, such as polarity, higher mechanical strength, and piezoelectric, ferroelectric, and pyroelectric properties), and two solvents, dimethyl sulfoxide (DMSO) and glyceryl triacetate (GTA). Pure solvent boxes are built using two force fields (Compass and Dreiding) to study the stabilization of their density and solubility, which are used with the PVDF surfaces (for each solvent, computations are performed using two surfaces α and β). According to the radial distribution function results, DMSO shows a stronger interaction with two PVDF phases, allowing it to orient chains from the α phase to the β phase, while GTA exhibits a weaker interaction due to specific hydrogen bonds. These findings are confirmed by the experiment, where the fraction F(β) reaches 62% when using DMSO, while it is 36% when using GTA.

Sustainable upgrading of crude glycerol via ultrasound-reinforced bio-refinery process with oxygen–nitrogen subsistence: Co-application of reusable heterogeneous catalyst

Selective/rapid production of value-added glyceryl triacetate (GT) from catalytic transformation of crude glycerol (CG) derived from biodiesel production procedure was systematically investigated using ultrasound-reinforced bio-refinery process with environmental friendliness. Interestingly, the tartaric-magnetic mesoporous alumina (TMMA) was synthesized via hydrothermal aluminization, calcination and functionalization, further applied as an active catalyst for CG acetylation under nitrogen and/or oxygen subsistence. The operative parameters for selective synthesis of GT derived optimization process were in the sequence of TMMA loading amount > ultrasonic level > acetylation time. The GT selectivity and activation energy derived from catalytic acetylation of CG using ultrasonic system were 97.78 % and 44.38 kJ/mol while traditional system were 52.51 % and 60.66 kJ/mol. For catalytic comparison, TMMA catalyst presented better turnover rate of CG transformation than that of marketable catalysts. Moreover, TMMA catalyst could be reused for 15 cycles without notable changing in physicochemical properties such as surface area and acidity which was contributed under oxygen subsistence by oxidative degradation, leading to long-term durability of catalytic performance and long-term repression of polymeric formation. The sustainable application of O2 molecular could perfectly restrain hard polymeric deposition on TMMA structure, leading to facile separation after complete acetylation. This work anticipated that specific integration between TMMA with CG acetylation can be further co-applied for practical process of biodiesel production using ultrasound-reinforced bio-refinery process.

Thermal aging performance of soybean insulating oil mixed with glyceryl triacetate

A method of delaying the aging of natural ester oil-paper insulation systems by adding glyceryl triacetate is proposed in this work. A study was conducted on the thermal aging performance of soybean insulating oil mixed with glyceryl triacetate at a volume fraction of 7.5%. Through a 42-day accelerated thermal aging experiment, it was found that the addition of glyceryl triacetate effectively delayed the increase in kinematic viscosity of the insulating oil and reduced the generation of aging products such as moisture and acid. However, the polar compounds in glyceryl triacetate reduced the breakdown voltage of the mixed oil and made the dielectric loss factor higher than that of pure oil. In addition, tests were conducted on the insulating paper immersed in two types of oil, and it was found that the addition of glyceryl triacetate helps to distribute mixed oil molecules on the surface of insulating paper, which effectively helped absorb moisture from the paper, weakening the hydrolysis reaction of cellulose and delaying the aging of insulating paper. In addition, the insulating paper immersed in the mixed oil maintains good power frequency breakdown voltage and dielectric properties throughout the thermal aging experiment.

Optimisation of the glycerol acetylation process using graphene oxide catalyst

Glycerol diversification from biodiesel production can be improved by converting it into high-value acetin products, for example, glyceryl monoacetate (MAG), glyceryl diacetate (DAG) and glyceryl triacetate (TAG) via the glycerol acetylation process with graphene oxide as a catalyst synthesised from Multi-Walled Carbon Nanotubes (MWCNT). Hummer's method was used to prepare graphene oxide. The acidity of the catalyst was examined, as well as FTIR, BET, XRD and SEM-EDX. This research aims to improve the glycerol acetylation to produce high glycerol conversion and acetins selectivity depending on the reaction circumstances. Process optimisation employs Response Surface Methodology (RSM) in conjunction with the Box-Behnken Design (BBD) method with three repeats of the midpoint. Temperature, mole ratio and catalyst loading (%) were all evaluated factors. The RSM process was optimised using Design-Expert software version 13, which resulted in a glycerol conversion of 93.04%. Moreover, with the selectivity of MAG 47.65%, DAG 29.21%, and TAG 23.36% at a temperature of 110°C, the mole ratio of glycerol and acetic acid (1:9) and the catalyst loading are 5%.

Epigenetic priming targets tumor heterogeneity to shift transcriptomic phenotype of pancreatic ductal adenocarcinoma towards a Vitamin D susceptible state

As a highly heterogeneous tumor, pancreatic ductal adenocarcinoma (PDAC) exhibits non-uniform responses to therapies across subtypes. Overcoming therapeutic resistance stemming from this heterogeneity remains a significant challenge. Here, we report that Vitamin D-resistant PDAC cells hijacked Vitamin D signaling to promote tumor progression, whereas epigenetic priming with glyceryl triacetate (GTA) and 5-Aza-2′-deoxycytidine (5-Aza) overcame Vitamin D resistance and shifted the transcriptomic phenotype of PDAC toward a Vitamin D-susceptible state. Increasing overall H3K27 acetylation with GTA and reducing overall DNA methylation with 5-Aza not only elevated the Vitamin D receptor (VDR) expression but also reprogrammed the Vitamin D-responsive genes. Consequently, Vitamin D inhibited cell viability and migration in the epigenetically primed PDAC cells by activating genes involved in apoptosis as well as genes involved in negative regulation of cell proliferation and migration, while the opposite effect of Vitamin D was observed in unprimed cells. Studies in genetically engineered mouse PDAC cells further validated the effects of epigenetic priming for enhancing the anti-tumor activity of Vitamin D. Using gain- and loss-of-function experiments, we further demonstrated that VDR expression was necessary but not sufficient for activating the favorable transcriptomic phenotype in respond to Vitamin D treatment in PDAC, highlighting that both the VDR and Vitamin D-responsive genes were prerequisites for Vitamin D response. These data reveal a previously undefined mechanism in which epigenetic state orchestrates the expression of both VDR and Vitamin D-responsive genes and determines the therapeutic response to Vitamin D in PDAC.

Glyceryl triacetate promotes blood–brain barrier recovery after ischemic stroke through lipogenesis-mediated IL-33 in mice

BackgroundLipid metabolism has a crucial role in neural repair in neurodegenerative diseases. We recently revealed that lipogenesis-mediated interleukin-33 (IL-33) upregulation lead to blood–brain barrier (BBB) repair after ischemic stroke. However, manipulating the key enzyme fatty acid synthase (FASN) to enhance lipogenesis was very challenging. Glyceryl triacetate (GTA) was used as a donor of acetate and precursor of acetyl coenzyme A, the key substrate for de novo lipogenesis catalyzed by FASN. Therefore, we hypothesized that GTA would promote lipogenesis the peri-infarct after ischemic stroke and contribute to the BBB repair through IL-33.MethodsMiddle cerebral artery occlusion (MCAO) was performed on C57BL mice and GTA was gavage administrated (4 g/kg) on day 2 and 4 after MCAO. Lipogenesis was evaluated by assessment of the protein level of FASN, lipid droplets, and fatty acid products through liquid chromatography-mass spectrometry in the peri-infarct area on day 3 after MCAO, respectively. BBB permeability was determined by extravasation of Evans blue, IgG and dextran, and levels of tight junction proteins in the peri-infarct area on day 7 after MCAO, respectively. Infarct size and neurological defects were assessed on day 7 after MCAO. Brain atrophy on day 30 and long-term sensorimotor abilities after MCAO were analyzed as well. The inhibitor of FASN, C75 and the virus-delivered FASN shRNA were used to evaluate the role of FASN-driven lipogenesis in GTA-improved BBB repair. Finally, the therapeutic potential of recombinant IL-33 on BBB repair and neurological recovery was evaluated.ResultsWe found that treatment with GTA increased the lipogenesis as evidenced by lipid droplets level and lauric acid content, but not the FASN protein level. Treatment with GTA increased the IL-33 level in the peri-infarct area and decreased the BBB permeability after MCAO. However, infarct size and neurological defect score were unchanged on day 7 after MCAO, while the long-term recovery of sensorimotor function and brain atrophy were improved by GTA. Inhibition of lipogenesis using C75 or FASN shRNA reversed the beneficial effect of GTA. Finally, exogenous IL-33 improved BBB repair and long-term functional recovery after stroke.ConclusionCollectively, we concluded that treatment with GTA improved the BBB repair and functional recovery after ischemic stroke, probably by the enhancement of lipogenesis and IL-33 expression.Graphical

Beef quality monitoring using immobilization lipase on modified polypropylene non-woven fabric based on time-temperature indicator

A lipase-based time-temperature indicator (TTI) was developed via the immobilization of lipase on polyethylene imine/glutaraldehyde/polypropylene non-woven fabric for the catalytic hydrolysis of glyceryl triacetate. pH of the reaction system gradually decreased and the color changed from green to orange or salmon pink. Four TTIs were selected by changing the concentration of glyceryl triacetate methanolic solution, the concentration of lipase-phosphate buffer solution, and the amount of phosphate buffer added, storing at 5–25 °C and measuring the coloration difference every 24 h. The Arrhenius activation energy (Ea) of obtained TTIs was calculated as 26.28, 47.98, 38.87, and 42.00 kJ/mol. For the application of TTIs to fresh beef monitoring, the kinetic properties of beef were studied and an Ea value of 37.60 kJ/mol was obtained. The similarity of these Ea shows accuracy in the prediction of beef quality with TTI color development.

Qualitative and Quantitative Analysis of Five Indoles or Indazole Amide Synthetic Cannabinoids in Suspected E-Cigarette Oil by GC-MS.

To establish the GC-MS qualitative and quantitative analysis methods for the synthetic cannabinoids, its main matrix and additives in suspicious electronic cigarette (e-cigarette) oil samples. The e-cigarette oil samples were analyzed by GC-MS after diluted with methanol. Synthetic cannabinoids, its main matrix and additives in e-cigarette oil samples were qualitatively analyzed by the characteristic fragment ions and retention time. The synthetic cannabinoids were quantitatively analyzed by using the selective ion monitoring mode. The linear range of each compound in GC-MS quantitative method was 0.025-1 mg/mL, the matrix recovery rate was 94%-103%, the intra-day precision relative standard deviations (RSD) was less than 2.5%, and inter-day precision RSD was less than 4.0%. Five indoles or indazole amide synthetic cannabinoids were detected in 25 e-cigarette samples. The main matrixes of e-cigarette samples were propylene glycol and glycerol. Additives such as N,2,3-trimethyl-2-isopropyl butanamide (WS-23), glycerol triacetate and nicotine were detected in some samples. The content range of synthetic cannabinoids in 25 e-cigarette samples was 0.05%-2.74%. The GC-MS method for synthesizing cannabinoid, matrix and additive in e-cigarette oil samples has good selectivity, high resolution, low detection limit, and can be used for simultaneous qualitative and quantitative analysis of multiple components; The explored fragment ion fragmentation mechanism of the electron bombardment ion source of indole or indoxamide compounds helps to identify such substances or other compounds with similar structures in cases.

Recycling of NCA cathode material from end-of-life LiBs via Glycerol-triacetate solvent -based separation

Currently, a challenging task for recycling both spent lithium-ion batteries and cathode scrap is the separation of cathode materials from the current collector. A promising and efficient recovery method is to use an organic solvent to dissolve the organic polyvinylidene difluoride (PVDF) binder to recover both cathode materials and aluminum foil. However, the use of toxic solvents hinders its practical application in recycling the large amounts of cathode scrap generated during the manufacturing process. The proposed solvent-based separation process uses glycerol triacetate, a bio-derived green solvent. This study investigates a closed-loop recovery process that recovers cathode materials, including Al foil and PVDF binder, from cathode scrap. Using the glycerol triacetate solvent, a closed-loop recycling process was developed. The glycerol triacetate separation process provides a sustainable platform for the recovery and reuse of electrodes, thereby contributing to battery recycling efforts.

Development of A Nanostructured Lipid Carrier-Based Drug Delivery Strategy for Apigenin: Experimental Design Based on CCD-RSM and Evaluation against NSCLC In Vitro.

Non-small-cell lung cancer (NSCLC) is the main cause of cancer-related deaths worldwide, with a low five-year survival rate, posing a serious threat to human health. In recent years, the delivery of antitumor drugs using a nanostructured lipid carrier (NLC) has become a subject of research. This study aimed to develop an apigenin (AP)-loaded nanostructured lipid carrier (AP-NLC) by melt sonication using glyceryl monostearate (GMS), glyceryl triacetate, and poloxamer 188. The optimal prescription of AP-NLC was screened by central composite design response surface methodology (CCD-RSM) based on a single-factor experiment using encapsulation efficiency (EE%) and drug loading (DL%) as response values and then evaluated for its antitumor effects on NCI-H1299 cells. A series of characterization analyses of AP-NLC prepared according to the optimal prescription were carried out using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). Subsequent screening of the lyophilization protectants revealed that mannitol could better maintain the lyophilization effect. The in vitro hemolysis assay of this formulation indicated that it may be safe for intravenous injection. Moreover, AP-NLC presented a greater ability to inhibit the proliferation, migration, and invasion of NCI-H1299 cells compared to AP. Our results suggest that AP-NLC is a safe and effective nano-delivery vehicle that may have beneficial potential in the treatment of NSCLC.

Are New Phthalate Ester Substitutes Safer than Traditional DBP and DiBP? Comparative Endocrine-Disrupting Analyses on Zebrafish Using In Vivo, Transcriptome, and In Silico Approaches.

Although previous studies have confirmed the association between phthalate esters (PAEs) exposure and endocrine disorders in humans, few studies to date have systematically assessed the threats of new PAE alternatives to endocrine disruptions. Herein, zebrafish embryos were continuously exposed to two PAEs [di-n-butyl phthalate (DBP) and diisobutyl phthalate (DiBP)], two structurally related alternatives [diiononyl phthalate (DINP) and diisononyl hexahydrophthalate (DINCH)], and two non-PAE substitutes [dipropylene glycol dibenzoate (DGD) and glyceryl triacetate (GTA)], and the endocrine-disrupting effects were investigated during the early stages (8-48 hpf). For five endogenous hormones, including progesterone, testosterone, 17β-estradiol, triiodothyronine (T3), and cortisol, the tested chemicals disturbed the contents of at least one hormone at environmentally relevant concentrations (≤3.9 μM), except DINCH and GTA. Then, the concentration-dependent reduced zebrafish transcriptome analysis was performed. Thyroid hormone (TH)- and androgen/estrogen-regulated adverse outcome pathways (AOPs) were the two types of biological pathways most sensitive to PAE exposure. Notably, six compounds disrupted four TH-mediated AOPs, from the inhibition of deiodinases (molecular initiating event, MIE), a decrease in T3 levels (key event, KE), to mortality (adverse outcome, AO) with the quantitatively linear relationships between MIE-KE (|r| = 0.96, p = 0.002), KE-AO (|r| = 0.88, p = 0.02), and MIE-AO (|r| = 0.89, p = 0.02). Multiple structural analyses showed that benzoic acid is the critical toxicogenic fragment. Our data will facilitate the screening and development of green alternatives.

Study on the Properties of Cellulose Acetate Composite Synergistically Toughened by Glycerol Triacetate and Modified Nano Titania

Glyceryl triacetate (GT) and nano titanium dioxide (TiO2) filler modified by titanate coupling agent were used to toughen cellulose diacetate to prepare CA/GT/nano TiO2@NZD-201 composites. The effects of glyceryl triacetate and modified titanium dioxide filler on the mechanical properties and rheological properties of cellulose acetate were studied. The rheological properties showed that glyceryl triacetate and modified nano TiO2 significantly increased the plasticity of the composite, reduced the complex viscosity, reduced the rigidity, and increased the viscoelastic ratio. The impact resistance of the composite was improved by 101% due to the addition of modified nano titanium dioxide.

Highly Active Nickel (II) Oxide-Supported Cerium Oxide Catalysts for Valorization of Glycerol into Oxygenated Fuel Additives.

Acetylation of glycerol to yield monoacetin (MAT), diacetin (DAT), and triacetin (TAT) over NiO-supported CeO2 (xNiO/CeO2) catalysts is reported. The catalysts were synthesized utilizing a sol-gel technique, whereby different quantities of NiO (x = 9, 27, and 45 wt%) were supported onto the CeO2 substrate, and hexadecyltrimethylammonium bromide (CTABr) served as a porogen. The utilization of EDX elemental mapping analysis confirmed the existence of evenly distributed Ni2+ ion and octahedral NiO nanoparticles on the CeO2 surface through the DRS UV-Vis spectroscopy. The most active catalyst is 27NiO/CeO2 based on TAT selectivity in the glycerol acetylation with ethanoic acid, attaining 97.6% glycerol conversion with 70.5% selectivity to TAT at 170 °C with a 1:10 glycerol/ethanoic acid molar ratio for 30 min using a non-microwave instant heating reactor. The 27NiO/CeO2 is reusable without significant decline in catalytic performance after ten consecutive reaction cycles, indicating high structure stability with accessible active acidity.

Batch and continuous γ-alumina-catalyzed FAME production from soybean oil deodorizer distillate by interesterification

This paper presents data for a batch and continuous fatty acid methyl esters (FAME) production through heterogeneous catalysis interesterification with methyl acetate, using soybean oil deodorizer distillate (SODD) as feedstock, a high-acid by-product of problematical destination, generated during the soybean oil refining process. As a reaction catalyst, γ-alumina with high catalytic activity, acid character, and an interesting specific area was synthesized and used in the processes. The SODD presented a significant FFA content of 35.2 ± 0.4 wt% and low convertibility in esters (48.0 ± 0.9 %) pointing to high impurity content. By statistical design, the parameters optimization (temperature, methyl acetate:SODD mass ratio, and catalyst load) of the batch reactor returned results that indicated the reliability and reproducibility of the proposed model, allowing predicting the system behavior at autogenous pressure, where around 80.0 wt% of ester yield and 5.4 wt% of triacetin (TA) yield was obtained after 2 h. By kinetics analysis, a FAME yield higher of 90 wt% and TA yield of 13.90 wt% were achieved after 4 h. From these results, continuous production of FAME and TA could be evaluated, where the results obtained permitted to affirm that the acid heterogeneous interesterification can be an interesting process to biodiesel synthesis from SODD.

Techno-Economic Assessment and Sensitivity Analysis of Glycerol Valorization to Biofuel Additives via Esterification.

Glycerol is a valuable feedstock, produced in biorefineries as a byproduct of biodiesel production. Esterification of glycerol with acetic acid yields a mixture of mono-, di-, and triacetins. The acetins are commercially important value-added products with a wide range of industrial applications as fuel additives and fine chemicals. Esterification of glycerol to acetins substantially increases the environmental sustainability and economic viability of the biorefinery concept. Among the acetins, diacetin (DA) and triacetin (TA) are considered high-energy-density fuel additives. Herein, we have studied the economic feasibility of a facility producing DA and TA by a two-stage process using 100,000 tons of glycerol per year using Aspen Plus. The capital costs were estimated by Aspen Process Economic Analyzer software. The analysis indicates that the capital costs are 71 M$, while the operating costs are 303 M$/year. The gross profit is 60.5 M$/year, while the NPV of the project is 235 M$ with a payback period of 1.7 years. Sensitivity analysis has indicated that the product price has the most impact on the NPV.

On the Effect of Monomeric and Polymeric Plasticizer on Polybutylene Succinate (PBS), Polyhydroxybutyrate (PHB), and Polylactic Acid (PLA) Films with 20wt%PCL for Flexible Packaging Application

Nowadays, biodegradable polymers such as Polybutylene succinate (PBS), Polyhydroxybutyrate (PHB), and Polylactic acid (PLA) are widely used commercially, especially in flexible packaging applications, but these polymers have certain limitations in their properties. The main aim of this study was to develop biodegradable polymer films with improved performance characteristics. This paper focused on developing and enhancing the characterization such as tensile properties, water barrier properties, and biodegradation properties of PBS-PCL(Polycaprolactone), PHB-PCL, and PLA-PCL blends, with the addition of 5wt% of plasticizer [GTA (Triacetin/ glycerol triacetate), a monomeric plasticizer P1, Ultramoll, a polymeric plasticizer P2; and mixed plasticizer P3 (1: 1 mix of P1 and P2)] for flexible packaging application. The plasticized polymer films (thickness 0.25mm) was prepared by injection molding and hot pressing method, and analyze the characterization such as tensile properties (ASTM D882-18 method), water vapor barrier properties (ASTM E96-16 method), and the biodegradation properties in compost (ASTM D5338-15 method), and seawater (ASTM D6991-17 method) medium, and analysis the effect of plasticizers on plasticized polymer blends. The research shows that compared to polymers blends such as PBS, PHB, and PLA, with 20wt% of PCL, there was a significant increase in tensile elongation by 22%,76.6%, and 139.3%, respectively and an increase in biodegradability by 19.5%, 3.6%, and 38.9% in compost medium, and 22.1%, 1.8%, and 41.0% in seawater medium, respectively, with the addition of all three 5wt% plasticizers (Ultramoll), though the tensile strength and water vapor properties were decreased. The plasticizer study shows that plasticized polymer blends using mixed plasticizer (P3) provide the best overall performance enhancement.

Glycerol acetylation over yttrium oxide (Y2O3) catalyst supported on palm kernel shell-derived carbon and parameters optimization studies using response surface methodology (RSM)

A biomass derived carbon supported yttrium oxide catalyst (Y2O3/PKS-T700) was synthesized and evaluated in glycerol acetylation reaction using four-factor, two-level face-centred central composite design (24 CCD) of the response surface methodology (RSM). The catalyst exhibited high glycerol conversion (GC) (99.8%) and product selectivity of 11.1%, 60.2%, and 29.6% monoacetin (MA), diacetin (DA) and triacetin (TA) under optimized conditions of temperature 130 ℃, glycerol-to-acetic acid molar ratio 1:12 and catalyst loading 0.5 g in 5 h reaction time. The catalyst was synthesized via carbonization of palm kernel shell (PKS), impregnated with 15 wt% yttrium oxide (Y2O3) and calcined appropriately. The synthesized catalyst was further characterized by N2 physisorption analysis (BET surface area), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infra-red (FTIR), and temperature programmed desorption-ammonia (TPD-NH3). Results revealed that the catalyst is more of mesoporous material with large surface area, good pore volume and average size distributions. It is thermally stable with good acidity and various functional groups. On subjecting the catalyst to a reusability test in three (3) reaction cycles under the optimal conditions, it was found to maintain good acetylation reaction with little degradation.

Rescue the cycle life of LiNi0.5Mn1.5O4 cathode on high voltage via glyceryl triacetate as the multifunction additive

The poor cyclic stability is the key point to restricting the commercial application of LNi0.5Mn1.5O4-based lithium-ion batteries (LNMO-based LIBs) on high voltage (5 V-class). Once the working voltage is over 4.3 V, the parasitic reactions on the LNMO interphase will be the trigger for a series of problems such as the continuous decomposition of electrolytes and dissolution of transition metal ions. The glyceryl triacetate (GT) has been used as a functional additive to reconstruct a cathode electrolyte interphase (CEI) film to suppress the parasitic reactions and safeguard the LNMO structure. Compared to the influence of GT and propionic anhydride (PA) on the electrochemical performance of LNMO on high voltage, the LNMO/Li cell with GT exhibits exciting discharge capacity retention of 84.9 % compared with PA (17.6 %) and base electrolyte (BE, 8.6 %) after 500 cycles at 1C. The LNMO/Li cell with GT also has a remarkable rate performance in which capacity retention of 5C/2C is 85.7%, higher than 0.5 wt% PA (75.5%) and BE (62.1%). By characterizations, it is reasoningly demonstrated that the GT not only can be preferentially oxidized to form a robust CEI film on the LNMO surface to prevent the parasitic reaction but also rapidly capture the free transition metal ions and bind trace H2O in the electrolyte to improve the stability of LIBs. Simultaneously, the electrons from the carboxyl group of GT occupy the d-orbital of transition metal from LNMO, further effectively reducing the activity of LNMO. Particularly, the glycerol generated by the reaction of GT with H2O can effectively capture HF, H2O, and other small molecules under hydrogen-bond interaction, thereby improving the stability of LNMO LIBs.