Dodecyl Amine Research Articles

Open-Circuit Technology of Zinc Oxide Ore Flotation with Ternary Collector and Its Adsorption Characteristics on Smithsonite Surface

The sulfidization-amine flotation method is commonly used for the beneficiation of zinc oxide ores. Lanping zinc oxide ores contains 8.40% zinc, with the main mineral being smithsonite; additionally, they have a high mud content. Conventional sulfidization–ammonium flotation presents a low flotation index and unsatisfactory flotation froth. A new open-circuit technology is employed to treat Lanping zinc oxide ores, where Na2S, KG-248, and dodecyl amine + sodium isoamyl xanthate + ammonium dibutyl dithiophosphate are used as the regulator, depressant, and ternary collector, respectively. Consequently, the flotation indices for the zinc grade and recovery are 28.71% and 86.24%, respectively, and the flotation froth becomes more stable. Subsequently, the flotation behavior and adsorption mechanism of smithsonite with a ternary collector are investigated. The flotation recovery of smithsonite increases to 94.40% after treatment with the ternary collector. Surface-analysis results indicate that the ternary collector can synergistically adsorb onto the sulfidized smithsonite surface to enhance its hydrophobicity, thus increasing the floatability of smithsonite. Meanwhile, the total consumption of the collector in the ternary-collector system is lower than that in the binary- or unitary-collector system.

Synthesis and in vitro study of biodegradable and thermoresponsive polymer based on polysuccinimide for drug delivery

Hydrogels, defined as polymer networks with a high water content and insoluble in water, have emerged as pivotal materials in biomedical research due to their resemblance to the natural extracellular matrix. The aim of this study is to develop an injectable, thermoresponsive, and biodegradable hydrogel. The hydrogel (PSI-t) was derived from poly (aspartic acid) (PSI) by grafting hydrophobic dodecylamine (DA) and hydrophilic ethanolamine (EA) groups onto its backbone. PSI-t was found to exhibit a unique sol state at room temperature, which facilitates facile injection, and undergoes rapid gelation at physiological temperatures, highlighting its potential as an injectable thermosensitive hydrogel for targeted drug delivery. In vitro tests confirmed the biocompatibility of the thermosensitive hydrogel, and sustained drug release studies using the model drug, acetaminophen (AP), underscored the efficacy of the hydrogel as a controlled release vehicle. Furthermore, the hydrogel was found to be easily eliminated through bio-hydrolysis, thus enabling prolonged drug effects while mitigating any potential toxicity. These findings suggest that PSI-t is a promising candidate for an innovative and injectable drug delivery system in biomedical applications.

Effect of organic matter with various carbon chain lengths on methane hydrate formation: Kinetic, thermodynamic, and microstructural studies

Organic matter is a pivotal component in methane hydrate (MH) deposition and plays a crucial role in the MH formation process due to its intricate chain structures. In this study, organic matters (OMs) with varying carbon chain lengths, including glycine, alanine, phenylalanine, 12-amino dodecanoic acid, dodecyl amine, and dodecanoic acid, were selected to investigate their impacts on the kinetics, thermodynamics, and microstructure of MH. Kinetic experimental findings reveal that long carbon chain OMs and OMs containing hydrophobic functional groups promote MH formation, with a more pronounced effect at higher concentrations. Conversely, short carbon chain OMs and OMs with hydrophilic functional groups exhibit kinetic inhibition of MH. Thermodynamic experiments show that the effect of OMs on the thermodynamics of MH at low concentrations (<1 wt%) is negligible. At higher concentrations, 12-aminododecanoic acid and dodecyl amine at 5 wt% make the phase equilibrium conditions of MH more moderate, while glycine at 3 wt% shows an inhibiting effect. Furthermore, the interaction between OMs functional groups, water and methane molecules influences MH crystals, alters crystal size and increases the proportion of large and small cages of MH. This study helps to understand the role of OMs in MH formation and promots an in-depth understanding and utilization of MH resources.

Selective flotation separation of gypsum and quartz using dodecyl amine hydrochloride as collector: Mechanism and application

The selective flotation separation of gypsum and quartz in phosphogypsum (PG) is an urgent problem that is very important for the high‐value utilization of PG. In the work, dodecyl amine hydrochloride (DH) was introduced as a collector for the selective flotation separation of gypsum and quartz. The flotation property and selective mechanism of DH on the surface of gypsum and quartz were researched by single mineral flotation experiments, Fourier transform attenuated total reflection infrared spectroscopy analyzer, zeta potential analyzer, X‐ray photoelectron spectrum, molecular dynamic (MD) simulation, etc. Additionally, H+ was introduced into the mineral‐water system simulated by MD to take into account the effect of acidic conditions on the adsorption of DH. The pre‐adsorption of H+ on the quartz surface under strongly acidic conditions hindered the electrostatic force adsorption of DH on the quartz surface. Furthermore, DH was adopted as a collector in the direct flotation recovery of gypsum from PG, and the gypsum concentrates with productivity of 69.85%, CaSO4·2H2O content of 96.33%, and whiteness of 55.00% were obtained. The SiO2 content in the gypsum concentrate decreased from 9.08% to 0.616%. It suggested that DH could serve as a promising collector in the selective separation of gypsum and quartz in PG via flotation.

Probing the Interaction Mechanism of Sodium Oleate and Dodecyl Amine with Quartz Surfaces in the Presence of Ca2+ Ions by AFM Force Measurement.

Quartz is a key raw material in high-tech fields (such as photovoltaics and semiconductor microelectronics), and the most efficient extraction method of quartz is mineral flotation. Quartz activation plays a crucial role in mineral flotation. However, the mechanism underlying the process remains unclear, and the role of additional metal ions is controversial. In this study, the interaction forces between the quartz surface, the dodecylamine (DDA) cation/sodium oleate (NaOL) anion mixed collectors, and Ca2+ were analyzed using atomic force microscopy in order to systematically explore the activation process of quartz flotation. The results confirmed that the activation process was initialized from NaOL, which was adsorbed on the surface of a calcium-covered quartz surface. The existence of DDA inhibited the binding of Ca2+ to NaOL so that more Ca2+ was adsorbed on the quartz surface to provide the adsorption site for NaOL. Moreover, the best adsorption condition of Ca2+ + NaOL + DDA mixed solution was analyzed by quartz crystal microbalance with dissipation, and it demonstrated that the most stable chemisorption environment on the quartz surface was at pH 11.0. In these circumstances, Ca2+ could first adsorb in a point-like manner on the quartz surface, which was then adsorbed with a mixture of NaOL and DDA. This result showed that, at a specific pH, Ca2+ could encourage the coadsorption of cationic/anionic mixed collectors on quartz. This work provides an important new understanding of the intermolecular interactions that take place during complex mineral flotation processes between chemical additives and mineral surfaces. The methodology used in this study can be easily adapted to different interfacial processes, including water treatment, membrane technology, bioengineering, and oil production.

Application of dodecyl amine/dodium petroleum sulfonate mixed collector in quartz-feldspar flotation separation

It’s highly challenging to separate feldspar from quartz by flotation owing to their similar crystal structure and physicochemical properties. Using mixed collectors has become a promising method to improve the quartz-feldspar separation. In this study, mixed dodecyl amine (DDA) and sodium petroleum sulfonate (SPS) surfactants were used in the flotation separation of feldspar and quartz, and the adsorption mechanism of mixed collectors and depression mechanisms of two depressants were investigated through zeta potential, contact angle and Fourier transform infrared (FT-IR) spectra. When the pH reached 4.5, the separation of feldspar from quartz was more obvious. In the presence of DDA/SPS collector, the contact angle of feldspar was increased more obviously leading to enhance hydrophobicity. The infrared spectra revealed the interaction of collectors on feldspar surface involved physical and chemical adsorption, whereas the adsorption of collector on quartz was only physical interactions. The use of sodium hexametaphosphate resulted in a significantly enhanced separation performance. The weaker physical adsorption of mixed collector on quartz can be destroyed by sodium hexametaphosphate. This study is beneficial for understanding the collect mechanisms of mixed cationic-anionic surfactants on quartz and feldspar minerals, and promotes the development of advanced feldspar separation techniques.

Facet-dependent magnetic properties of magnetite nanoparticles coated with dodecyl amine and their biological effect in hepatocarcinoma cell line

Herein was conducted a compelling structural analysis of magnetite nanoparticles (NPs) coated with dodecyl amine (DDA), compared with uncoated magnetite, both previously synthesized by an accelerated one-pot synthesis, starting from a single iron precursor. XRD/TEM results for the obtained nanomaterial Fe3O4@DDA showed the predominance of Fe3+ cations on the most stable atomic plane of magnetite (111). Using Molecular Dynamics calculations, with the observed atomic dispositions as inputs, it was established that NPs' surface and DDA might interact by short-distance coordination, with DDA as a ligand of Fe3+ cations, or by long-distance adsorption via H-bonding. The simulations align with TEM images, revealing an amorphous contour corresponding to the organic coating arranged as a bilayer. The TGA analysis corroborated a dual mass loss profile relating to the DDA bilayer at 116 °C and 350 °C. The Fe3O4@DDA NPs’ magnetic properties (saturation magnetization (Ms) and coercivity field (Hc)) were preserved. Fe3O4@DDA exhibited a reduction of 3 emu/g in Ms and an increment of 12 Oe in Hc, compared with Fe3O4 NPs, attributable to the coating inhomogeneity and the consequent anisotropy rise. Fe3O4@DDA triggered concentration-dependent cytotoxic effects on the human hepatocarcinoma cell line HepG2. At 50 µg/mL after incubation of 48 h, cell viability was 63% < , whereas at 72 h only 30% of cells were viable. At 300 µg/mL, less than 10% of HepG2 cells remained viable after 24 h of incubation. In the case of Fe3O4 NPs assessed in the same cell line, cell viability remained as high as 80% at 300 µg/mL during 72 h of incubation. Trypan blue assay suggests membrane integrity damage as the primary mechanism of HepG2 cell death. Even though the in vitro results herein presented are preliminary, they represent the first report of the cytotoxic effect of magnetite coated with a nitrogenous surfactant.Graphical abstract

Beach Sand-derived Mesoporous Silica by Hydrothermal Process for Hydrocracking Waste Coconut Oil to Biofuel

&lt;p&gt;Hydrocracking, a key process for converting waste coconut oil into biofuel, requires efficient catalysts. This study investigates the synthesis of mesoporous silica catalysts using a hydrothermal process. Dodecyl amine, sourced from beach sand, serves as a template. The hydrothermal synthesis involved durations (12, 15, 18, 21, and 24 hours) and dodecyl amine concentrations (0.25 M, 0.5 M, 0.1 M), conducted at 40 °C for 30 minutes. The synthesized catalysts were then characterized for their surface area, pore volume, and diameter. Among the synthesized samples, those treated for 15 hours displayed optimal total acidity at 0.88 mmol/g. The catalysts synthesized with a dodecyl amine concentration of 0.025 M exhibited superior characteristics, including a specific surface area of 233 m²/g, a pore volume of 0.47 cc/g, and an average pore diameter of 2.10 nm. These findings underscore the efficacy of mesoporous silica catalysts in hydrocracking, particularly in converting large hydrocarbon molecules into smaller, more valuable biofuel molecules. Comparative analysis with similar research highlights the significance of these findings in the field of sustainable energy. The optimal catalyst conditions yielded a liquid fraction of over 70% for 0.25 M dodecyl amine. This efficiency in converting waste coconut oil into biofuel signifies the potential of mesoporous silica catalysts in advancing environmentally friendly energy sources. This research contributes to the growing knowledge of renewable energy, offering promising avenues for developing sustainable and eco-friendly energy solutions.&lt;/p&gt;

Protonation reaction at the air/water interface monitored by a bubble Fabry-Perot interferometer

A novel interferometric technique for studies of exothermal chemical reactions at the water surface is presented. The key feature of the technique is the use of an air bubble as the interface which hosts coating molecules and at the same time acts as a subnanometer-sensitive Fabry-Perot interferometer which follows the bubble radius change after a chemical reaction with coating molecules. As an example we report measurements of a protonation reaction with dodecyl-amine (DA). A monolayer of the DA surfactant is formed at the gas-liquid interface of a millimeter-sized bubble immersed in a 10.6 pH solution. After the monolayer formation, the residual DA is removed from the bulk by gentle rinsing. Interference with the DA bulk reaction is avoided. Protonation is induced by HCl injection. The reaction in the thin DA coating layer generates a non-trivial evolution of the bubble radius with amplitude oscillations of the order of 10−3 of the bubble radius with persisting time of a few hundred seconds. Measurements are performed at different DA coverages of the bubble surface, always below the maximum coverage. Control experiments with non-coated bubble show no amplitude radius oscillations. Formation and stability of the DA monolayer are precisely monitored by measurements of the lowest-frequency bubble capillary mode. A possible interpretation of the experiments is given in terms of heat effects, vapor production and surface modification. Molecular Dynamics simulations provide a mechanistic understanding of surface effects triggered by the protonation reaction which promotes desorption of positively charged DA micelles.

Kinetics and outer sphere electron transfer of some metallosurfactants by Fe(CN)6 4− in microheterogenous medium: a detailed thermodynamic approach

Abstract We report the rate of electron transfer reaction of complexes, cis-[M(ED)2(DOD)2]3+ (1), cis-[M(DP)2(DOD)2]3+ (2), cis-[M(TRE)(DOD)2]3+ (3), cis-[M(bpy)2(DOD)2]3+ (4) and cis-[M(PA)2(DOD)2]3+ (5) (M:Co, ED: ethylenediamine, TRE: triethylenetetramine, DP: diaminopropane, PA: phenanthroline, C12H25NH2: dodecylamine (DOD) and bpy: bipyridine) and hexacyanoferrate ion in surface active ionic liquids (BMIM)Br were studied at 298–323 K by electronic absorption spectroscopy. Surfactant complexes 4 and 5, which have a higher ETR than complexes 1–3 based on the results obtained, have been explained based on the states of aggregation and hydrophobic transformations between the hydrocarbon portion of the surfactant compounds and (BMIM)Br. As a result, surface-active agent micelles in (BMIM)Br and increase ETR in between the system. The investigation of kinetic statistics outcomes suggest that reduction reaction between surface-active agent Co(III) complexes and hexacyanoferrate occurs via 2nd order and the ET is proposed as outer sphere. The remarkable increase in the rate for the ETR in (BMIM)Br with increase in the concentration of Co(III) complexes from 1–5. This can be attributing due to the fact those reactants with opposite charges and the amphipilicity of the ligand. The OSET of kinetics have been confirmed by the enthalpy and entropy (ΔS # and ΔH #) factors, and the isokinetic plots (ΔS # versus ΔH #) have shown that the reaction’s mechanism does not alter during the (BMIM)Br medium.

Influence of polyolefin modified by Y2O3 as protective coatings against carbon steel corrosion into 3.5% NaCl media

In this research work, we have studied the impact of Yttrium nanoparticles loaded with corrosion inhibitors dodecylamine (DOC) incorporated in polyolefin for the corrosion protection of steel. The surface analysis of pure polyolefin and polyolefin-Y2O3-DOC composite coatings by atomic force spectroscopy (AFM) shows that both of the coated samples’ roughness almost remain the same. Furthermore, the contact angle measurement shows an increase in the hydrophobicity of polyolefin-Y2O3 with inhibitor. The release behavior of the corrosion inhibitors DOC was also studied at different pH. The x-ray diffraction for the loaded product shows that no physical and structural changes occur during the loading of the corrosion inhibitor. The electrochemical impedance spectroscopy (EIS) analysis demonstrates that smart polyolefin-Y2O3-DOC coating has better anticorrosion properties than pure polyolefin coating due to the effective release of DOC. An increase in charge transfer and pore resistance confirms the better barrier properties of the polyolefin-Y2O3-DOC composite coating. The inhibition efficiency of the polyolefin modified by Y2O3 increased by 99% as compared to pure polyolefin coating. The carbon steel substrate became stable and the polymeric composite coating protectected the steel against corrosion in the oil and gas industry. In conclusion, the study shows that yttrium nanoparticles loaded with corrosion inhibitors incorporated in polyolefin have a significant impact on the corrosion protection of steel.

Reaction-induced liquid crystalline polybenzoxazine thermosets using aryl ester bonds as cross-linkages

ABSTRACT The increasing tendency to develop integration in electronic devices lead to the demand for thermally conductive polymeric materials. We offered a simple synthetic route to thermally conductive polybenzoxazine thermosets bearing liquid crystalline structures without the addition of any filler. Benzoxazine monomer of BZ-COOH was synthesized via Mannich reaction of p-hydroxy benzoic acid, p-formaldehyde, and dodecyl amine. After ring-opening polymerization of BZ-COOH, the obtained benzoxazine oligomer of OBZ-COOH was converted into acetoxy-bearing benzoxazine oligomer of OBZ-AC. Through self-crosslinking reaction of acetoxy group and carboxyl group in OBZ-AC using Zn(CH3COO)2 as a catalyst, the polybenzoxazine thermosets of OBZ-PES were produced. The liquid crystalline behavior of OBZ-AC was studied by POM, SAXS, and DSC. The results show that OBZ-AC formed the LC mesophase during isothermal and non-isothermal curing. The LC mesophase displays a layered arrangement of the smectic C phase. The formation mechanism is esterification reaction-induced. Owing to the formation of liquid crystalline structure, the TC of OBZ-PES is found to be 0.284 W/m. K, which is 21% and 16% greater than those of OBZ-COOH and OBZ-AC, respectively. In addition, the OBZ-PES shows excellent thermal performance. Its Tg(G”) is up to 269°C. Its 5% weight loss temperature (Td5) and 10% weight loss temperature (Td10) are 383°C and 410°C, respectively.

Reaction-Induced Liquid Crystalline Polybenzoxazine BearingAromatic Amide Side Branches.

In this study, a nematic phase structure is incorporated into polybenzoxazine to increase its thermal conductivity. A simple route for the synthesis of a thermally conductive polybenzoxazine containing liquid crystalline (LC) structure by grafting oligomeric p-sulfophenylene-terephthalamide (PSTA) is offered. Benzoxazine monomer of pHBA-da is synthesized via Mannich reaction of p-hydroxy benzoic acid, p-formaldehyde, and dodecyl amine. After ring-opening polymerization, the oligomer benzoxazine of OBZ─COOH is obtained. The OBZ─COOH/PSTA mixture is prepared by mixing PSTA with OBZ─COOH. Afterward, the grafted copolymer is named OBZ─PSTA copolymer. The liquid crystalline behavior of OBZ─COOH/PSTA is studied by polarized optical microscopy and small angle X-ray scattering analysis. The results show that the OBZ─PSTA forms the LC structure during isothermal and non-isothermal curing. The LC structure displays a floral textured nematic phase. The phase formation is induced by an amidation reaction. Due to the grafts of LC PSTA, the thermal conductivity of OBZ─PSTA is 0.296W m-1 K-1 , which is 26% greater than OBZ─COOH. The glass transition temperature (Tg ) of OBZ─PSTA is 241°C. The 5% (Td5 ) and 10% weight loss temperatures (Td10 ) of OBZ─PSTA are 346 and 362°C, respectively.

Mixed Anionic/Cationic Collectors for Pyrite Flotation: An Experimental and Theoretical Study

ABSTRACT The presence of pyrite causes harmful environmental and metallurgical effects during the pyrometallurgical processes of metals. Hence, various processing methods should minimize the amount in the feed. Meanwhile, flotation is one of the most common methods due to the natural hydrophobic property of the pyrite surface. Based on this premise, this research focuses on the efficiency of pyrite flotation using mixed anionic/cationic collectors as one of the significant factors of flotation. This study is organized and performed in two laboratory and simulation sections. Lab-scale studies consider the kind of collector(s), collector(s) concentration, size, frother concentration, and pH as practical factors. Dodecyl amine (DDA), potassium amyl xanthate (PAX), and Sodium Isopropyl Xanthate (SIPX) are three types of collectors examined in the single and mixed forms for pyrite flotation. In the simulation part, adsorption of a single form and mixed forms of collectors on the pyrite (001) surface and its effects on the wetting property of the surface is investigated using the molecular dynamics approach. In sum, the results of this study show that, although pyrite has the favorable ability of flotation with anionic collectors from the xanthate family (PAX and SIPX) due to its natural hydrophobic feature, the presence of a cationic collector (DDA) significantly enhances its flotation performance so that a 1:1 mixture of DDA and PAX with a concentration of 15 for each collector, at pH 7, and the presence of an A65 as frother (30 ), increases the flotation recovery of pyrite by more than 95%.

Multilayered LDH/Microcapsule Smart Epoxy Coating for Corrosion Protection.

A multilayered smart epoxy coating for corrosion prevention of carbon steel was developed and characterized. Toward this direction, as a first step, zinc-aluminum nitrate-layered double hydroxide (Zn/Al LDH) was synthesized using the hydrothermal crystallization technique and then loaded with dodecylamine (DOD), which was used as an inhibitor (pH-sensitive). Similarly, the synthesis of the urea-formaldehyde microcapsules (UFMCs) has been carried out using the in-situ polymerization method, and then the microcapsules (LAUFCs) were encapsulated with linalyl acetate (LA) as a self-healing agent. Finally, the loaded Zn/Al LDH (3 wt %) and modified LAUFCs (5 wt %) were reinforced into an epoxy matrix to develop a double-layer coating (DL-EP). For an exact comparison, pre-layer epoxy coatings comprising 3 wt % of the loaded Zn/Al LDH (referred to as LDH-EP), top-layer epoxy coatings comprising 5 wt % linalyl acetate urea-formaldehyde microcapsules (referred to as UFMLA COAT), and a blank epoxy coating (reference coating) were also developed. The developed epoxy coatings were characterized using various techniques such as XRD, XPS, BET, TGA, FTIR, EIS, etc. Electrochemical tests performed on the synthesized coatings indicate that the DL-EP demonstrates improved self-healing properties compared to LDH-EP and UFMLA COAT.

Dodecylamine encapsulation in layered smectite clay mineral: Release and application for copper corrosion inhibition in 0.1 M nitric acid solution

The economic and environmental impact associated to the use of corrosion inhibitors for metal protection directs research works towards systems based on the encapsulation of these active principles for a more sustainable approach. Here, dodecylamine (DA) was intercalated in the interlayer space of a smectite and the intercalated amine once released, was used as copper corrosion inhibitor in 0.1 M nitric acid solution. The effective synthesis of the organoclay was confirmed by X-ray diffraction, infrared spectroscopy and thermogravimetric analysis. The inhibition percentages obtained by electrochemical methods increased with the release time (from 55% after 0.5 h to 90% after 24 h). This result indicates a slow release of intercalated amine present in the organoclay. Gravimetric monitoring of corrosion experiments performed continuously for 28 days confirm the decrease of copper corrosion rate with release time. Based on thermodynamic studies and surface analysis by scanning electron microscopy, the released amine was physiosorbed on copper surface, leading to the formation of a film that protect the metal against nitrates and dissolved oxygen, responsible of the cathodic reactions that initiates copper corrosion.

Development of Hydrophobic-Modified Nanosilica for Pressure Reduction and Injection Increase in an Ultra-Low-Permeability Reservoir

A low-permeability reservoir contains many fine pore throat structures, which result in excessive injection pressure of the water injection well and difficult water injection in the production process of a low-permeability reservoir. In this study, a new silane coupling agent was synthesized via the ring-opening reaction between dodecyl amine and KH-560 (γ-propyl trimethoxysilane). The modified KH-560 was reacted with nano-SiO2 to synthesize the modified nano-SiO2 as an antihypertensive additive. Fourier infrared spectroscopy, thermogravimetric analysis and laser scattering were used to characterize this modified nano-SiO2. The results show that the particle size of the modified nano-SiO2 is less than 60 nm. The test results of the water contact angle show that the dispersion system can increase the rock contact angle from 37.34° to 136.36°, which makes the rock surface transform from hydrophilicity to hydrophobicity and reduce the binding effect of rock with water. The dispersion test shows that the modified nano-SiO2 has good dispersion stability under alkaline conditions with TX-100 (Polyethylene glycol octylphenyl ether) as the dispersant. The antiswelling test results show that the antiswelling rate of this modified nano-SiO2 is 42.9%, which can efficiently prevent the clay expansion in the formation to reduce the injection pressure. The core displacement test results show that its depressurization rate reaches 49%. The depressurization rate still maintains 46% at a 20 PV water flow rate, indicating that its depressurization effect is remarkable and it has excellent erosion resistance.

Improving the Solar Energy Utilization of Perovskite Solar Cells via Synergistic Effects of Alkylamine and Alkyl Acid on Defect Passivation

Defects in perovskite film are sources of charge recombination centers, which are detrimental to the performance of perovskite solar cells (PSCs). To decrease the density of defects, dodecylamine (DAM), dodecylic acid (DAC), and 12‐aminolauric acid (ALA) are utilized as additives to prepare methyl ammonium lead iodide (MAPbI3) perovskite films. Herein, the passivation effects of these molecules on the properties of the MAPbI3 films and the performances of the corresponding PSCs are studied. The results show that DAM and DAC which contain –NH2 and –COOH groups, respectively, can increase the PCEs of the devices. This result implies that both groups serve as the Lewis base, passivating the defects of undercoordinated Pb2+. For the ALA molecules, the –NH2 and –COOH groups are present simultaneously at the two ends of the molecule; the passivation ability is more significant than the others, which is attributable to the synergistic effects of the two groups. By the passivation of ALA, the PCE of the PSC can increase from 18.42% to 19.96% under one sun illumination. Furthermore, the treatments of the passivation agents also increase the hydrophobicity of the perovskite films, improving the stability of the PSCs.

Functionalized Magnetite Nanoparticles Using Two New Ionic Liquids for Efficient Oil Spill Cleanup

Recently, magnetite nanoparticles (MNPs) have gained great attention for oil spill cleanup due to their unique properties, e.g., high oil removal efficiency, high surface area, and response to an external magnetic field. The efficiency of MNPs for oil spill uptake can be enhanced by functionalizing their surface using different materials. Furthermore, the functionalization of MNP surface using these materials promotes their chemical stability. This study aims to functionalize the surface of magnetite nanoparticles (MNPs) using two newly synthesized hydrophobic ionic liquids (ILs) and apply them for oil spill cleanup. ILs were synthesized by the reaction of glycidyl-4-nonyl ether (GE) with fatty amines, either octadecylamine (OA) or dodecylamine (DA), to yield the corresponding amines, GEOA and GEDA, respectively. GEOA and GEDA were quaternized with acetic acid (AA) to produce the corresponding ILs, GEOA-IL and GEDA-IL. The produced ILs, GEOA-IL and GEDA-IL, were applied for the surface modification of magnetite nanoparticles (MNPs), producing surface-modified MNPs, GO-MNPs and GD-MNPs, respectively. GO-MNPs and GD-MNPs were characterized using Fourier transform infrared, X-ray diffraction, transmission electron microscopy, dynamic light scattering, contact angle, and vibrating sample magnetometer. Their oil removal efficiency (ORE) was investigated at different MNP : crude oil ratios ranging from 1 : 1–1 : 50. GO-MNPs and GD-MNPs showed high ORE even at low MNP ratios. Furthermore, GO-MNPs showed higher oil removal efficiency than GD-MNPs, which may be explained using GEOA-IL containing a longer alkyl chain for MNP surface modification in comparison to GEDA-IL. Furthermore, GO-MNPs and GD-MNPs displayed excellent reusability in five cycles, with a slight decrease in ORE with increasing cycles.

A low temperature demulsifier with double hydrophobic chains was prepared by a one-step method

A demulsifier (PEDA) with double hydrophobic chain structure was synthesized using polyethylene glycol diglycidyl ether (PEDGE) and dodecyl amine (DA) as starting materials by a one-step method. The PEDA was characterized by FT-IR, 1H NMR and thermogravimetric analysis (TGA). It was used for the demulsification of two water-in-crude oil (W/O) emulsions (mwater:moil = 70:30 and mwater:moil = 10:90). The effect of PEDA concentration, settling time, demulisification temperature, pH value and salinity on the demulsifying efficiency (DE) were detailly discussed in the W/O emulsions. The results showed that the DE of PEDA could reach 91.78% and 100% in the 70:30 and 10:90 emulsion at 50 °C for 240 min, respectively. Also, PEDA had excellent acid, alkaline and salt resistance. In addition, some commercial demulsifiers were used for comparison to evaluate the demulsification ability of PEDA. The dynamic interfacial tension (IFT), three-phase contact angle (CA), zeta potential and optical microscopic observation were used to investigate the demulsifying mechanism. The current study not only develops a new PEDA demulsifier with excellent performance at lower temperature but also provides a simple synthesis method for the demulsifier using less variety of raw materials, so it is more conducive to the industrial applications.