Octadecyltrimethylammonium Chloride Research Articles

Single and Double Alkyl Chain Quaternary Ammonium Salts as Environment-Friendly Corrosion Inhibitors for a Q235 Steel in 0.5 mol/L H2SO4 Solution

In this work, the corrosion inhibition effects of octadecyl trimethyl ammonium chloride (OTAC) and dioctadecyl dimethyl ammonium chloride (DDAC) on Q235 steel in a 0.5 mol/L H2SO4 solution are studied. The results of the electrochemical experiment, contact angle measurement, and scanning electron microscopy indicate that the two ionic liquids belong to mixed-type corrosion inhibitors with good anti-corrosion performance. Additionally, OTAC has a better anti-corrosion ability than DDAC, implying that the steric hindrance effect of the double alkyl chain is not conducive to the adsorption of DDAC on the electrode surface.

Efficient and stable perovskite solar cells: The effect of octadecyl ammonium compound side-chain

The extreme vulnerability of hybrid perovskite solar cells (PSCs) to moisture greatly limits the realization of their full potential. Here, we propose an efficient strategy to reinforce the efficiency and the ambient stability of PSCs via employing a series of octadecyl ammonium salts (OASs): octadecyl trimethyl ammonium chloride (OTAC), octadecyl dimethyl benzyl ammonium chloride (ODBAC), and 3-(trimethoxysilyl)propyl octadecyldimethyl ammonium chloride (TOAC), as passivating agents. Among these OASs, TOAC bearing a trimethoxysilane (Si-O-CH3) side chain group most efficiently promoted the efficiency along with the high-humidity stability of PSC devices. TOAC significantly passivated the defects, assisted better energy-level alignment and facilitated charge carrier transport in the devices. The TOAC-passivated PSCs exhibited an increase in the average PCE from 16.62 ± 0.56 % to 20.06 ± 0.68 % with a substantially enhanced fill factor of 80.10 ± 1.82 %. Furthermore, the unencapsulated TOAC-passivated PSCs preserved 90 % of their performance after storage in ambient conditions (25–30 ℃, 50–70 % relative humidity) for 300 h. When no OAS passivator was introduced, the devices were losing more than 74 % of their starting PCE after 150 h. The Si-O-CH3 groups side-chained to the OAS molecules were capable of supporting superior protection to the PSC devices against the permeation of high-moisture. Thereupon, the application of multifunctional octadecyl ammonium salt molecules to passivate defects and tailor the interface energy-level alignment in PSCs offers an encouraging staging to upgrade the PV performance of PSCs.

Eco-friendly composite nanofibrous membranes loaded with chitosan microcapsules for enhanced antibacterial and deodorant application

Traditional textiles are conductive to breed germs that might cause infection or unpleasant odor, especially in public hygiene products. Moreover, biosafety, environmental protection and cost are crucial considerations for antimicrobial materials. Herein, we developed a biocompatible microcapsules/nanofibrous membrane using eco-friendly and facile strategy. The microcapsules loaded with the Epigallocatechin and gallate (EGCG) were synthesized through an ion-crosslinking reaction between chitosan (CS) and sodium tripolyphosphate (TPP). Additionally, the addition of octadecyl trimethyl ammonium chloride (STAC) could further enhance the antibacterial activity. Following that, the microcapsules were combined with the polycaprolactone (PCL) nanofibers. The resultant composite nanofibrous membrane exhibits a slow release effect, an enjoyable deodorant activity, and strengthened antibacterial activity through contact-killing and biocide-releasing. Besides, the membrane behaved a low degradation rate, without compromising its mechanical and hydrophilic properties after a 20-day degradation. These findings provided a biocompatible and practical approach for antimicrobial and odor-proof material for hygienic and sanitary products.

Preparation and Properties of Organically Modified Na-Montmorillonite.

This study investigates the montmorillonite (MMT) content, rotational viscosity, and colloidal index of sodium montmorillonite (Na-MMT) as a function of the sodium agent dosage, reaction time, reaction temperature, and stirring time. Na-MMT was modified using different octadecyl trimethyl ammonium chloride (OTAC) dosages under optimal sodification conditions. The organically modified MMT products were characterized via infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The results show that the Na-MMT with good properties (i.e., the maximum rotational viscosity and highest Na-MMT content with no decrease in the colloid index) was obtained at a 2.8% sodium carbonate dosage (measured based on the MMT mass), a temperature of 25 °C, and a reaction time of two hours. Upon organic modification of the optimized Na-MMT, OTAC entered the NA-MMT interlayer, and the contact angle was increased from 20.0° to 61.4°, the layer spacing was increased from 1.58 to 2.47 nm, and the thermal stability was conspicuously increased. Thus, MMT and Na-MMT were modified by the OTAC modifier.

Suppression of anthracite dust by a composite of oppositely-charged ionic surfactants with ultra-high surface activity: Theoretical calculation and experiments

In this study, we developed composite anionic–cationic (AC) surfactants with ultra-high surface activity using sodium alpha olefin sulfonate and octadecyltrimethylammonium chloride to improve the wettability and dust suppression efficiency of coal dust. Moreover, we investigated the synergistic suppression mechanisms of AC surfactant compounds at a molecular level. The thermodynamics of the self-assembly suggested that the surfactant molecules in the composite solution form a flexible alternating anion–cation bilayer. The analysis of the critical micelle concentration (CMC), surface tension (24.121 mN·m−1), contact angle (35.14°) and settling time (18 s) of the composite surfactant solution proved the superior performance of our composite surfactants compared to the monomeric alternatives, resulting in enhanced wettability owing to an ultra-high surface activity. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) experiments revealed an increased number of hydrophilic groups on the surface of the composite surfactant-treated anthracite, explaining the microscopic mechanism behind the high wettability induced by the composite surfactant. The specific surface area and pore size distribution of anthracite before and after dust suppressant treatment were calculated, and it was concluded that the dust suppressant was adsorbed on the surface and in the pores of the anthracite. In addition, the microscopic external morphology of the anthracite was shown by scanning electron microscopy (SEM), and it was found that the dust suppressant showed filling and aggregation behavior. Wind erosion and evaporation resistance experimental results show that dust suppressant-treated coal dust has enhanced water retention and wind resistance. Our findings indicate that ionic surfactants with oppositely charged compounds are promising high-efficiency dust suppressants, laying the foundation for safe coal mining and providing a theoretical background for a broad range of applications, such as haze control.

Preparation and the foaming activity of hydroxymethyl octadecyltrimethyl ammonium chloride

Abstract In this work, hydroxymethyl octadecyltrimethyl ammonium chloride (HM-OTAC) was obtained from the reaction between octadecyltrimethyl ammonium chloride (OTAC) and formaldehyde in different molar ratios. The effects of the reaction conditions (different molar ratios) on the properties of the product (surface tension, foaming, high temperature resistance, methanol resistance and salt resistance) were investigated. The results showed that the HM-OTAC produced under different molar ratios could lower the surface tension of water solutions more than the surfactant OTAC. The HM-OTAC (1:2) reduced the surface tension to 28.29 mN m−1. The HM-OTAC produced under other molar ratios gave higher interfacial tensions than HM-OTAC (1:2). With increasing surfactant concentration, the foam volume first increased and then gradually decreased. At a concentration of 0.3 wt.%, the highest foam volume (460 mL) was produced with HM-OTAC (1:3). Compared to OTAC, the foams produced by each HM-OTAC surfactant exhibited higher temperature stability. In the presence of 30 mL methanol, the initial foam volume of all HM-OTAC surfactants (0.3 wt.%) was generally higher than that of OTAC. With 300 mL HM-OTAC (1:4) solution, the highest foam volume of 20.2 mL could be produced. HM-OTAC (1:3) showed the highest salt resistance.

Preparation and Cr (VI) Removal Performance of a New Positively Charged PVC Microfiltration Membrane

Poly (vinyl chloride co dimethyl aminoethyl methacrylate) (PVD) and polyvinyl chloride (PVC) were blended, and then the tertiary amine groups of PVD in the casting solution were quaternized in situ with methyl iodide (CH3I) at 60. A new strongly charged positive PVC/PVD (M1) microfiltration membrane was prepared by non solvent induced phase transformation (NIPS), and PVC (M0) microfiltration membrane was prepared and compared with it. The membrane performance parameters such as morphology, pore size, charge, hydrophilicity and pure water flux of M0 and M1 were characterized. The cationic surfactant Octadecyltrimethylammonium chloride (STAC) micelle enhanced filtration was used to remove trace Cr6+(Cr2O7 2-) from the solution. The effects of Cr6+ concentration, pH value and sodium chloride (NaCl) concentration on the interception performance were investigated. The results show that the rejection rate of Cr6+ removal by M1 membrane micelle enhancement is close to 100%. When the mass ratio of Cr6+/STAC is greater than 0.478, the rejection rate of Cr6+ removal by M1 decreases with the increase of Cr6+ concentration; PH value has little effect on the retention of Cr6+ by M1; High concentration of NaCl reduced the rejection rate of Cr6+ by M1. M1 microfiltration membrane has potential development prospects in the treatment of wastewater containing Cr6+.

Enhanced Red Emissions of Europium (III) Chelates in RNA–OTMA Complexes

In recent years, biopolymers have been widely used in optoelectronic devices because of their unique structure, novel optical and physical properties. In this paper, novel RNA-based photofunctional materials were fabricated by associating an RNA–OTMA (octadecyltrimethylammonium chloride) lipid complex with a luminescent Eu (III) complex. The fluorescence emission intensity, fluorescence quantum yield and fluorescence lifetime were characterized in both solution and thin film states, and the interaction between the RNA–OTMA lipid complex and Eu (III) complexes was analyzed. This study suggests that the luminescence performance of the Eu (III) complexes doped with RNA–OTMARNA–OTMA was significantly enhanced compared with those of the complex in a conventional poly (methyl methacrylate) matrix, thereby providing an important basis for the application of biomaterials in optoelectronic devices.

Enhanced Mn2+ solidification and NH4+-N removal from electrolytic manganese metal residue via surfactants

Electrolytic manganese metal residue (EMMR) harmless treatment has always lacked a low-cost and quick processing technology. In this study, surfactants, namely tetradecyl trimethylammonium chloride (TTC), sodium dodecyl benzene sulfonate (SDBS), sodium lignin sulfonate (SLS), and octadecyl trimethylammonium chloride (OTC), were used in the solidification of Mn 2+ and removal of NH 4 + -N from EMMR. The Mn 2+ and NH 4 + -N concentrations under different reaction conditions, Mn 2+ solidification and NH 4 + -N removal mechanisms, and leaching behavior were studied. The results revealed that the surfactants could enhance the Mn 2+ solidification and NH 4 + -N removal from EMMR, and the order of enhancement was as follows: TTC ＞ SDBS ＞ OTC ＞ SLS. The NH 4 + -N and Mn 2+ concentrations were 12.3 and 0.05 mg·L -1 with the use of 60.0 mg·kg -1 TTC under optimum conditions (solid–liquid ratio of 1.5:1, EMMR to BRM mass ratio of 100:8, temperature of 20 °C, and reaction duration of 12 h), which met the integrated wastewater discharge standard (GB8978-1996). Mn 2+ was mainly solidified as Mn(OH) 2 , MnOOH and MnSiO 3 , and NH 4 + -N in EMMR was mostly removed in the form of ammonia. The results of this study could provide a new idea for cost-effective EMMR harmless treatment.

Performance Evaluation of an Octadecyltrimethyl Ammonium Chloride-Dimethyl Silicone Oil as a Waterproof Locking Agent in Low-Permeability Reservoirs.

Low porosity and permeability of oil and gas reservoirs make it difficult to develop these resources. To address these problems, we developed and evaluated a novel, environmentally friendly waterproof locking agent, which was prepared using dimethyl silicone oil and octadecyltrimethylammonium chloride and characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and particle size measurement. The waterproof locking performance of the agent was evaluated in a low-permeability reservoir using surface tension and contact angle measurements, and thermodynamic calculations were performed. The average particle size or median diameter (D50) of a 1% mother liquor was 325 nm at 20 °C and 470.8 nm at 70 °C. The contact angle of clean water on the core surface increased from 10 to 110°. At 70 °C, the surface tension of water was reduced to 24 mN·m–1, indicating good waterproof locking performance. The interaction parameters were calculated in accordance with the Langmuir adsorption theory. The increase in temperature from 20 to 70 °C reduced Γmax from 4.59 × 10–6 to 1.36 × 10–6 mol·m–2 and ΔGθ from −40.93 to −56.54 kJ·mol–1. Thus, the adsorption behavior of the developed locking agent is believed to improve the productivity of oil wells.

Adsorption Characteristics of Ionic Surfactants on Anthracite Surface: A Combined Experimental and Modeling Study.

Ionic surfactants are widely used in coal dust control in mines, and their adsorption characteristics on the coal surface have a great influence on the coal dust control effect. In this investigation, anionic sodium dodecylbenzenesulfonate (SDBS) and cationic octadecyltrimethylammonium chloride (STAC) were selected to explore the adsorption characteristics of ionic surfactants on the surface of anthracite. The experimental results show that the adsorption rate and efficiency of STAC on the surface of anthracite are higher than that of SDBS; STAC can form a denser surfactant layer on the surface of anthracite, with a larger adsorption capacity and higher strength. Molecular dynamics simulations show that the adsorption between STAC and the surface of anthracite is tighter, and the distribution at the coal–water interface is more uniform; the surface of anthracite modified by STAC has a stronger binding ability to water molecules.

Viscoelastic micellar system of mixed surfactin and octadecyl trimethyl ammonium chloride

AbstractSurfactin is a kind of lipopeptide biosurfactant with good performance. In order to solve the difficulty of surfactin thickening, this study investigated the new viscoelastic micellar system composed of surfactin and octadecyl trimethyl ammonium chloride (OTAC) and its rheological properties. The influences of mass ratio, pH, and temperature on the rheological properties of the system were studied. Under optimized mass ratio and pH, the maximum viscosity of surfactin/OTAC (4.5/7.5 w/w, pH = 5.34) is obtained as 13,904 mPa s. The flow curves of surfactin/OTAC micelle system can be described by Cross constitutive equation. The rheological properties of surfactin/OTAC viscoelastic micelle systems are obtained, including thixotropy, viscoelasticity, and viscosity‐temperature properties. The research on the new surfactin/OTAC system expanded the viscoelastic micelle systems of microbial surfactant series, which was expected to provide the rheological basis for the research of the surfactin micellar systems and be applied to the development and production of daily chemical industry, oil recovery, and other fields.

Kinetics‐Controlled Synthesis of {100}‐Facet‐Enclosed Gold Quasi‐Square Nanosheets with Curved Edges

Planar gold nanocrystals with a non-conventional quasi-square morphology, mainly enclosed with {100} facets, were successfully prepared via glutathione-mediated one-pot synthesis under kinetics control, exhibiting an enhanced electrochemical activity for methanol oxidation in alkaline medium.

How does coal interact with organic groups in an aqueous solution?

Interactions between coal matrix and organics are vital for adsorption [1], surfactant adsorption on lignite [2-5], and solid–liquid separation of coal slurry [6-10]. Herein, for studying the interaction between hydrophobic surface (coal surface) and small molecules (organics), we measured interactions between organics [nitro and phenyl, pyridine, phenyl, alkyl chain (hexyl) or cycloalkyl (hexyl)] and the coal matrix (liptinite or inertinite) using atomic force microscopy. The strength of interaction followed the order: nitro and phenyl > pyridine > phenyl > alkyl chain (hexyl) > cycloalkyl (hexyl), and liptinite > inertinite. The liptinite has a greater hydrophobicity than inertinite, the greater the attraction force. The lignite surface and coal slurry were modified in an aqueous solution using five surfactants (dodecyl trimethyl ammonium chloride, DTAC; hexadecyl trimethyl ammonium chloride, CTAC; octadecyl trimethyl ammonium chloride, STAC; hexadecyl dimethyl benzyl ammonium chloride, HDBAC; and cetyl pyridine chloride, CPC). Subsequently, the moisture adsorption on treated lignite coal surface and the sedimentation of the treated tails was compared to characterize hydrophobic modifications which showed the order of CTAC > HDBAC > DTAC > CPC > STAC. Thus, the interaction between coal surface and organics needs to consider two rules: 1) The desolvation or the hydrophobic property of the coal surface; 2) The VDW force of the organics. The nature of the difference between rules No. 1 and 2 is that with the size of hydrophobic molecules increased to a surface, the H-bond structure between water molecules in the around would change a lot, which formats great hydrophobic property or desolvation. SynopsisInteraction between organic reagents and coal reveals the mechanism of restraining moisture reabsorption of lignite and solid–liquid separation of coal slurry by organics.

Experimental research on synergistic drag reduction of cationic surfactant and nonionic polymer

The coupling of surfactant and polymer can weaken their shortcomings, improve drag reduction rate, and enhance the stability of drag reduction. This paper takes the cationic surfactant octadecyl trimethyl ammonium chloride and the nonionic polymer polyethylene oxide as the research objects, and uses the coaxial cylinder system of Anton Paar MCR102 to study the synergistic drag reduction of cationic surfactant and nonionic polymer. The experimental results show that cationic surfactants and nonionic polymers has obvious synergistic drag reduction. Compared with 800 ppm OTAC/NaSal solution or 40 ppm PEO solution, the drag reduction increases by 61.49% and 19.78%, respectively. Moreover, the drag reduction rate of the mixed solution is not monotonically increasing with the surfactant concentration. When the OTAC/NaSal concentration reaches polymer saturation point of 1200 ppm, the drag reduction rate of the mixed solution reaches the maximum value of 14.09% and the drag reduction rate increases by 34.15%; when the concentration of OTAC/NaSal is less than 1200 ppm, the drag reduction rate increases with the increase of the concentration of cationic surfactant; however, when the concentration of OTAC/NaSal is greater than 1200 ppm, the drag reduction rate is basically stable. In addition, the shear resistance of the mixed solution is significantly enhanced.

Regioselective Approach to Characterizing Increased Edge Availability in Layered Crystal Materials following Layer Expansion: Reaction of Kaolinite with Octadecyltrimethylammonium Salts.

In this paper, the regioselective reactions of kaolinite and methoxy-modified kaolinite (MeO-Kaol), methanol-expanded kaolinite, with octadecyltrimethylammonium salts are compared. This study mainly concerns the reactions of kaolinite or MeO-Kaol with octadecyltrimethylammonium chloride (C18TAC) in methanol and the subsequent exhaustive washing of the resultant products with ethanol. X-ray diffraction patterns of the products reveal no intercalation of C18TAC between pristine kaolinite layers. Additionally, intercalation and subsequent deintercalation of C18TAC proceed in the product using MeO-Kaol. In the Fourier-transform infrared spectra, the intensities of CH2 stretching bands of the product prepared using MeO-Kaol drastically increase compared to those using kaolinite. In addition, CH2 stretching bands of the product using kaolinite are hardly observed without enlarging the spectrum. The product using MeO-Kaol also displays mass loss in the range of 200–300 °C in the thermogravimetric curve and a nitrogen content with 0.15 mass% estimated using the CHN analysis. These results therefore demonstrate an increase in the available reactive edges in the layered crystal material following an expansion of the stacked layers.

Dispersion and Swellability of Ternary Surfactant Co-Modified Montmorillonites

AbstractOrgano-montmorillonite (OMnt) has wide applications in paints, clay-polymer nanocomposites, biomaterials, etc. In most cases, the dispersibility and swellability of OMnt dictate the performance of OMnt in the target products. Previous studies have revealed that the properties can be improved when multiple organic species are co-introduced into the interlayer space of montmorillonite (Mnt). In the present study, single surfactant erucylamide (EA), dual-surfactants cetyltrimethyl ammonium bromide (CTAB) and octadecyltrimethyl ammonium chloride (OTAC), and ternary-surfactants EA, CTAB, and OTAC were co-introduced into Mnt by solution intercalation. The resulting OMnts were characterized by powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetry-differential thermogravimetry (TG-DTG), water contact-angle tests, scanning electronic microscopy (SEM), laser particle-size analysis, and swelling indices. Mnt co-modified by ternary CTAB, OTAC, and EA led to a large d001 value (4.20 nm), surface hydrophobicity with a contact angle of 95.6°, swellability (50 mL/g) with small average particle sizes (2.1−2.8 μm) in xylene, and >99% of the OMnt particles were kept as <5 μm in deionized water. The formation of EA-modified-Mnt was proposed according to hydrophobic affinity, hydrogen bonding, and van der Waals forces. The nanoplatelets of the CTA+, OTA+, and EA co-modified OMnts in xylene were assembled into a house-of-cards structure by face-to-edge and edge-to-edge associations. The electrostatic attractions, electrostatic and steric repulsions, and hydrophobic interactions were responsible for the good dispersibility of OMnt in xylene. The ternary surfactant co-modified OMnt with high dispersion and swellability will make OMnt better suited for real-world applications.

Development, performance evaluation and enhanced oil recovery regulations of a zwitterionic viscoelastic surfactant fracturing-flooding system

A novel viscoelastic surfactant (VES) fracturing-flooding system composed of amphoteric surfactant octadecyl hydroxypropyl sultaine (OCHSB), cationic surfactant octadecyl trimethyl ammonium chloride (OTAC) and p-toluene sodium sulfonate (NaPts) is proposed to greatly enhance oil recovery. The synergistic effects of two surfactants and counterions were explored and the optimal dosage was determined. Rheological tests show that the system has excellent viscoelastic properties and shear resistance. The shear viscosity of the system with the addition of 4.8 wt% is higher than 25 mPa·s at 80 °C and 170 s−1. Meanwhile, the drag reduction rate of the system can reach more than 70%. In addition, the system breaks the gel thoroughly, has excellent anti-swelling properties, and the damage to the formation is less than 5%. Finally, the enhanced oil recovery regulations of the system were studied through flooding experiment, and its mechanism was analyzed. The enhanced recovery proves that the system has the dual effects of fracturing and flooding.

One-pot synthesis of yolk-shell Cu/Cu2O nanospheres with tunable morphologies for assisting photocatalytic hydrogen evolution

We report a facile, one-pot synthesis of spherical Cu/Cu 2 O yolk-shell nanocrystals (Cu/Cu 2 O YSNSs) with tunable morphologies and explored their applications for assisting photocatalytic hydrogen evolution. The success of current synthesis relies on the reduction of Cu(NO 3 ) 2 by ascorbic acid in the presence of octadecyl trimethylammonium chloride (OTAC) and hexamethylenetetramine (HMTA). It is found that the variation of OTAC concentration would lead to the formation of Cu/Cu 2 O YSNSs with tunable morphologies. The as-prepared Cu/Cu 2 O YSNSs are further anchored by TiO 2 nanoparticles (Degussa P25) to construct Cu/Cu 2 O/TiO 2 nanocomposites for applications in photocatalytic H 2 evolution under simulated sunlight irritation. The resulting metal-semiconductor nanostructures have remarkable photocatalytic activity in H 2 evolution from water-methanol mixtures, with the product rate being almost 97 times greater than that of the pure P25 catalysts. Such improvement should be attributed to the unique hollow structure and the presence of multi-valent copperish species. The current study describes a feasible one-pot strategy to synthesize copperish oxide nanocrystals with tunable yolk-shell morphologies and validates their promising use in as co-catalyst for photocatalytic hydrogen evolution to illustrate the advantage from both the structure and composition. Yolk-shell Cu/Cu 2 O nanospheres with tunable morphologies are prepared in high purity via a one-pot method. By anchoring with TiO 2 nanoparticles (P25), they exhibit excellent photocatalytic activity (~97 times greater than P25 in hydrogen production rate) and long-term durability towards photocatalytic hydrogen evolution, illustrating the structural and morphological advantages.

Physical properties of deep eutectic solvents based on p-toluene sulfonic acid and employment as catalyst

This work studied the physical properties of three deep eutectic solvents (DESs) and their catalytic activity in the esterification of palmitic acid and ethanol. Three types of deep eutectic solvents (DESs) were successfully prepared using p-toluene sulfonic acid monohydrate (PTSA) as hydrogen bond donor (HBD) with dodecyl trimethyl ammonium chloride (DTAC), tetradecyl trimethyl ammonium chloride (TTAC) and octadecyl trimethyl ammonium chloride (OTAC) as hydrogen bond acceptor (HBA). The freezing points of DESs were measured in the range of 50%–80% HBD mole percentage, and the composition of DTAC-PTSA, TTAC-PTSA and OTAC-PTSA at the eutectic point (the lowest freezing points) was determined respectively (DES1, DES2 and DES3). The physical properties (density, refractive index, dynamic viscosity, conductivity and pH value) of DES1∼DES3 were studied respectively in the temperature range of 298.15 K to 343.15 K. The results showed that dynamic viscosity, conductivity, density and refractive index all change approximately regularly with the increase of temperature, while pH value remains almost constant when the temperature exceeds 325 K. The catalytic ability of the three DESs in the esterification reaction of palmitic acid and ethanol was investigated, and DES2 was selected as the catalyst for subsequent experiments. The effects of temperature, acid-ethanol molar ratio, catalyst dosage and reaction time on esterification reaction were further studied, and DES’ recyclability was also tested. The results obtained showed the great potential of DES in catalytic applications.