Organic Bath Research Articles

Large-scale preparation of composite membranes for CO2 separation via interfacial polymerization: Monomer selection and processing parameter optimization

The increasingly serious situation of CO2 emissions compels researchers to pay extensive attention to industrial processes for carbon capture. Membrane-based separation technology is widely regarded as a promising reserve method for carbon capture, featuring a wide adjustment range, flexible operation and modular design. In this work, a large-scale interfacial polymerization membrane production process for carbon capture was developed together with the construction of novel interfacial polymerization equipment with an adjustable organic phase bath and surface cross-linking unit. A monomer suitable for efficiently preparing high-performance CO2 separation membranes was selected through a combination of experiments and simulations. The effect of production conditions on the structure and performance of large-scale membranes was investigated. The performance resilience at high pressure and short-term stability in the presence of impurities of the optimized membranes were examined. Techno-economic evaluation targeting carbon capture from post-combustion gas verifies the significant industrial application potential of the membranes.

Chemical Composition and Acceptability of Organic Bath Soap among Students in Yaba College of Technology, Yaba, Lagos State, Nigeria

The study determined the chemical composition and acceptability of organic bath soap among students in Yaba College of Technology, Yaba, Lagos State, Nigeria. The study was guided by two research questions. Mixed method research design was used for the study. Population was 46 which comprised all Home Economics students from the Department of Vocational Education. In-home use questionnaire was used for data collection. The study produced two samples of turmeric bath soap. Findings showed that the chemical compositions of the turmeric soap samples are in accordance with the specifications of the Standard Organization of Nigeria (SON) with toilet soap specifications of pH ranging from 9 to 11, total fatty matter ranging from 60-75 gm and total free caustic soda ranging from 0.05 to 0.08 %. Findings showed that the sensory evaluation attributes for colour, smell, consistency foam ability and skin sensitivity were accepted after use for three months as the samples were skin friendly, safe to use without side effects. It was recommended that turmeric body soap and turmeric face gel can be produced in large quantities for commercial purpose as a form of income generation for unemployed graduates.

RECYCLING OF LIQUID CRYSTALS FROM E-WASTE

For several decades, Liquid Crystal Displays (LCDs) have been widely used in televisions, laptops, mobile phones, and other devices. Nowadays, liquid crystals (LCs) represent an important economic value of the recycling system of LCDs. The reuse of these organic molecules could become a profitable basis since it permits to preserve the value of these materials. In this context, the general objective of this work focuses on the recovery of LCs as well as on other valuable materials present in end-of-life LCDs. An orderly, manual LCD dismantling line is put into operation for differentiated recycling of electronic boards, cold cathode lamps that may contain mercury, polymers, metals, and other valuable materials. There is also an extraction line where LCD panels are opened and exposed to an ultrasonically activated organic solvent bath to recover LCs. The resulting solution contains LCs, solvent, organic and inorganic impurities. The LCs mixtures were purified and then characterized mainly by spectroscopic, chromatographic, and thermal techniques. A study of the influence of adding diamond nanoparticles at 0.05, 0.1 and 0.2 wt% to recycled LCs was also performed using dielectric spectroscopy. Dielectric properties of LCs were measured at room temperature, using an impedance analyzer in the frequency range from 0.1 to 106 Hz.

The formation of TiO2 nanoporous/nanotubular structure on NiTi substrate with amorphous, nanocrystalline and microcrystalline structures

In the present study, the formation of TiO2 nanotube arrays on different NiTi substrates with different structures and crystallite sizes were investigated. In this regards, the anodizing process has been carried out in an organic bath (ethylene glycol+ 0.5 wt% NH4F+ 3 wt% water) under applied voltages of 10–90 V on as prepared microcrystalline, amorphous and nanocrystalline NiTi substrates. Based on results, the optimum anodizing voltage for the successful achievement of the nanotube arrays on microcrystalline NiTi substrate with the average grain size of 50 μm was estimated about 30–45 V. Increasing the applied voltage from 30 to 45 V resulted in an increase in the nanotubes diameter from 50 to 70 nm. The formation of nanotubes array was impossible on NiTi substrate with amorphous structure and only porous TiO2 formed on that. The response of nanocrystalline NiTi substrates against anodizing was in direct relation with crystallite size and changed from nanoporous to nanotubular with increasing the crystallite sizes from 40 to 350 nm.

Comprehensive Characterization of All Inorganic and Organic Components in Neutral Tin Plating Bath for Electronics Applications

Abstract Tin plating at neutral and near-neutral pH is the preferable process in the application of electronic components such as capacitors and resistors, where the chemically sensitive ceramic and glass portions can be damaged by highly acidic solutions (often used in semiconductor packaging processes). Stannous ions are not as stable at elevated pH due to oxidation and hydrolysis, and plating demands the use of a large number of additives making the process control very challenging. Various analytical techniques are developed for automatic and comprehensive characterization of all inorganic and organic bath components including simultaneous detection of conductive salt, anti-whisker and chelator by near-infrared (NIR) spectroscopy, brightener by potentiometric titration, stannous ions by electrochemical method, and the breakdown stannic ions by spectro-titration.

Simultaneous phase-inversion and crosslinking in organic coagulation bath to prepare organic solvent forward osmosis membranes

Organic solvent forward osmosis (OSFO) is an emerging separation process, which can realize simultaneous concentration of pharmaceutical ingredients and solvent recovery. In this work, a time-saving preparation process for solvent-resistant support layers was proposed by a simultaneous phase-inversion and crosslinking (SIM) method. The SIM method combines the formation of porous polyimide (PI) support layer and crosslinking between the PI and hexanediamine (HDA) in the coagulating baths, thus avoiding an extra need of solvent-based synthesis step. Furthermore, isopropanol (IPA) was used as coagulation bath for solvent-resistant PI support layers preparation, which can more effectively retarding the phase-inversion process compared with the DI-water. In addition, the morphologies and properties of these support layers with different synthesis time were prepared and characterized. After interfacial polymerization reaction using the as-prepared solvent-resistant PI support layers, the resultant OSFO membranes exhibited reasonable ethanol fluxes, lower reverse salt fluxes, and excellent pharmaceutical (oxytetracycline, OTC) rejections in both forward and reverse osmosis modes. Moreover, the long-term tests of as-prepared OSFO membranes indicated an excellent stability in 10 h operation with ethanol. After 10 h activation using DMF, the ethanol fluxes of OSFO18h membranes with different thickness of solvent-resistant support layers were significantly improved without sacrificing OTC rejection, which furtherly demonstrated the timeliness of SIM method and potential application of OSFO process in both concentrate the pharmaceutical and solvent recovery.

Comment on “Electrochemical Preparation and Characterization of Nanostructured Ag-Bi Thin Films in Organic Baths” [Electrochem. Solid-State Lett., 9, C32 (2006)

Comment on “Electrochemical Preparation and Characterization of Nanostructured Ag-Bi Thin Films in Organic Baths” [Electrochem. Solid-State Lett., 9, C32 (2006)

Electrochemical synthesis of self-organized TiO2 crystalline nanotubes without annealing

This work demonstrates that upon anodic polarization in an aqueous fluoride-containing electrolyte, TiO2 nanotube array films can be formed with a well-defined crystalline phase, rather than an amorphous one. The crystalline phase was obtained avoiding any high temperature annealing. We studied the formation of nanotubes in an HF/H2O medium and the development of crystalline grains on the nanotube wall, and we found a facile way to achieve crystalline TiO2 nanotube arrays through a one-step anodization. The crystallinity of the film was influenced by the synthesis parameters, and the optimization of the electrolyte composition and anodization conditions (applied voltage and time) were carried out. For comparison purposes, crystalline anatase TiO2 nanotubes were also prepared by thermal treatment of amorphous nanotubes grown in an organic bath (ethylene glycol/NH4F/H2O). The morphology and the crystallinity of the nanotubes were studied by field emission gun–scanning electron microscopy (FEG–SEM) and Raman spectroscopy, whereas the electrochemical and semiconducting properties were analyzed by means of linear sweep voltammetry, impedance spectroscopy, and Mott–Schottky plots. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) allowed us to determine the surface composition and the electronic structure of the samples and to correlate them with the electrochemical data. The optimal conditions to achieve a crystalline phase with high donor concentration are defined.

Microstructure, texture and tensile behavior of pulsed electrodeposited Ni–Al composites produced using organic additive-free sulfamate bath loaded with Al nanoparticles

Nickel and Ni–Al composites with varying Al nanoparticle content were produced by pulsed electrodeposition using an organic additive-free sulfamate bath. The as-deposited Ni–Al composites exhibited increased compressive residual stresses with increasing Al nanoparticles. Detailed microstructural investigation revealed that Al codeposition led to significant refinement of the columnar morphology and grain structure of Ni matrix along with a texture change from strong 〈001〉 to 〈011〉 fiber texture parallel to the growth direction. The as-deposited Ni with bimodal grain structure displayed good tensile strength and ductility. The microhardness and tensile strength of the Ni deposits were increased initially with Al content and then decreased at higher particle content. Particle induced grain refinement and texture changes could be related to change in the growth of upcoming Ni nuclei on to the surface of well-dispersed Al nanoparticles. Significant grain refinement and lesser internal stresses along with good particle distribution and relatively harder ⟨011⟩ fiber texture at lower particles concentration collectively contributed to the observed higher strengths in Ni–Al composites as compared to Ni deposits. There was substantial change in fracture morphology from spherical dimples to flat regions with increasing Al content due to agglomeration of nanoparticles at higher particle loading.

Electrodeposition of Al from Dimethyl Sulfone-Aluminum Chloride Baths Under Dry Air

Electrodeposition of Al requires the use of a non-aqueous bath, and it is usually carried out under an inert gas atmosphere such as nitrogen and argon using a glove box to protect the bath from absorbing moisture. However, the operation of the electrodeposition process under such conditions reduces the producibility and increases the cost, hindering its industrialization. If Al electrodeposition can be carried out in dry air, it would facilitate the operation and drastically lower the process cost. In this study, we examine the feasibility of the electrodeposition of Al under dry air using an organic bath, dimethylsulfone (DMSO2)-AlCl3 system (1-6). The electrodeposition of Al was carried out at 110°C under dry air with a dew point of ~−60°C in a dry chamber. The electrodeposition was also carried out under Ar atmosphere using a glove box, and the deposits obtained under the two atmospheres were compared. Cyclic voltammetry and XRD analysis of the deposits confirmed that the Al metal can be electrodeposited from the DMSO2-AlCl3 bath even in dry air. However, the Al film obtained in dry air tended to have black spots and a rough surface with scratch-like non-deposited portions. In contrast, a uniform, flat, silver-white Al film covering entirely the surface of the substrate is electrodeposited in Ar atmosphere under the same conditions, except for the atmosphere. This poor appearance of the Al film electrodeposited in dry air could be resolved by adding an additive to the bath. The current efficiency for the Al electrodeposition was slightly lower in dry air than that in Ar atmosphere, but it was still higher than 90%.

Preparation and characterization of TiO2 nanotube arrays on Ti6Al4V surface for enhancement of cell treatment

Fabrication and characterization of TiO2 nanotube arrays on Ti6Al4V surface for enhancement of cell treatment in biomedical applications was the aim of this study. In this regard, the anodizing process has been carried out in an organic bath (ethylene glycol+0.5wt% NH4F+3wt% water) under applied voltages of 25 to 100V. The anodized samples were characterized using scanning electron microscopy (SEM), hydrophilic/hydrophobic balance, cell attachment, ion release test and MTT assay. Based on achieved results, the nanotube arrays with good uniformity, high wettability and viability can successfully formed on Ti6Al4V surface in voltage range of about 50 to 75V. The dimensional characteristics of formed nanotubes depend on applied voltage and play an essential role in viability and cell adhesion. In this work, the formed nanotubes array in applied voltage of 60V (with average diameter and thickness of about 90–97 and 20–30, respectively) showed the best wettability, viability and cell response in comparison with other voltages.

Forward‐osmosis‐aided concentration of fructose sugar through hydrophilized polyamide membrane: Molecular modeling and economic estimation

ABSTRACTIn this study, a thin‐film composite membrane based on hydrophilized polyamide was synthesized for the concentration of an aqueous fructose solution using a forward‐osmosis (FO) technique. The membrane was prepared by the addition of excess m‐phenylenediamine along with a small quantity of dipolar aprotic dimethyl sulfoxide solvent in the aqueous reaction bath followed by excess trimesoyl chloride in an organic bath with a longer time provided for interfacial polymerization to minimize fructose losses. The effect of operating parameters such as draw NaCl concentration, cross‐flow velocity, and temperature on FO performance was evaluated. Membrane characterization was performed using scanning electron microscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction to study the physicochemical properties. A coupled model based on molecular modeling and computational fluid dynamics was developed to study the diffusion behavior and concentration profiles of the two solutions within the process. A detailed economic estimation for the production of crystalline fructose sugar is presented. The study reveals the significant potential of FO as an economical process for concentration of sugar solutions using brine as the draw solution. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44649.

Mechanical and physical properties of electrodeposited Ni-Fe, WO3 doped nanocomposite

Abstract The mechanical and magnetic properties of Ni-Fe alloy deposits may be controlled by compositional tailoring and reinforcement by ceramics. The incorporation of high content of ceramic particles in the alloy matrix has, however, detrimental effect on electrical and magnetic properties of the nanocomposites. Here, electrodeposition of WO3 nanoparticle (spheroidal shaped, 20–40 nm) doped Ni-Fe nanocomposites has been carried out in an organic bath at various current densities. The particle content in coating was found up to ~ 2.0 wt%. Field emission scanning electron microscope (FESEM), energy dispersed X-ray analyzer (EDAX) and atomic force microscopic (AFM) examinations revealed a distinct change in morphology of the deposit due to inclusion of the particles in the matrix. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies showed fcc lattice of the matrix and a shift in preferred orientation of the coating from (111) to (220) crystallographic planes with increasing current density. Significant enhancement in the microhardness of the coatings was observed on incorporation of only 1.25 wt% WO3 particles due to solid solution hardening and dispersion hardening. An improvement in the conduction and corrosion resistance of the coatings over matrix has also been noticed due to dispersion of the ceramic particles in the matrix. Magnetic studies point to ferromagnetic behavior of the nanocomposite which also has the tendency of superparamagnetism.

Fabrication of Photocatalytic Al-TiO2 Coatings By Composite Electrodeposition and Anodization

Metal matrix composite coatings containing TiO2 particles have been investigated, with the aim of obtaining coatings with additional functionality by taking advantage of the excellent photocatalytic ability of TiO2. Composite electrodeposition is known to be an effective technique for the fabrication of composite coatings of a metal matrix containing finely dispersed inert particles. The electrodeposition of coatings containing TiO2 particles with the metallic matrix being Ni, Ni-Mo alloy, Cu, Ag, and Zn has been reported. However, simple composite coatings composed of a metal matrix and uniformly dispersed TiO2 particles would not exhibit strong photocatalytic functions, because most of the TiO2 particles in the coatings are enclosed by the metal matrix and thus cannot exert their photocatalytic activity. Only the particles exposed on the surface of the coating can catalyze the reaction. One of possible ways to enhance the photocatalytic activity of the composite coatings is to make the matrix porous so that reactants can be in contact with the TiO2 particles located deep inside the coating. If Al is employed as the matrix, a well-known anodizing process can be used to convert the solid Al matrix into a porous Al oxide layer, although it is unclear if the porous structure can be formed even when inert particles are present in the Al layer. In this study, we investigated the feasibility of the formation of high-photocatalytic-activity Al-TiO2 composite coatings by electrodeposition using an organic bath and subsequent anodization. The structures of the anodized layer formed on the Al-TiO2 composite coatings, and the effect of the anodization on the photocatalytic activity of the coatings were examined. Al coatings containing TiO2 particles were obtained by electrodeposition from a bath composed of dimethyl sulfone, anhydrous AlCl3, and TiO2 powder. Surface and cross-sectional SEM observation and EDX analysis confirmed that TiO2 particles were uniformly present in the Al layer with a thickness of ~40 μm. The TiO2 content in the electrodeposited layer increased with increasing TiO2 content in the bath, and reached a maximum value of ~30 vol.%. The obtained Al-TiO2 composite coatings were subsequently anodized in oxalic acid at a voltage of 40 V for 30–90 min, followed by immersion in phosphoric acid to widen the pores. SEM observation of the surface and a fractured cross-section of the anodized coatings confirmed that an oxidized layer containing many pores with a diameter of <30 nm extending in the direction toward the substrate was formed on the surface of the coating. The mean interval between the pores was ~100 nm. TiO2 particles with 100–1000 nm sizes dispersed in the porous oxidized layer could also be observed. The photocatalytic activity of the coatings was examined by measuring the decomposition rate of methylene blue on the coatings under ultraviolet irradiation. The photocatalytic ability of the coatings increased with the TiO2 content in the coatings. Compared with the as-deposited coatings, the anodized coatings showed a higher photocatalytic ability. An increase in the photocatalytic ability was also observed with increasing anodization time. This should be attributable to the increase in the thickness of the porous layer and the resultant increase in the number of TiO2 particles accessible to the reactants. These results demonstrated that Al-TiO2 composite coatings can be formed by electrodeposition using an organic bath, and anodization of the composite coatings can create a porous Al oxide layer containing TiO2 particles on the surface of the coatings. By carrying out anodization, the photocatalytic activity of the composite coatings could be enhanced.

Electrodeposition of Aluminum from 1,3-Dimethyl-2-Imidazolidinone/AlCl3 baths

This study investigated the use of novel organic solvent baths for the electrodeposition of aluminum at near-ambient temperatures. It was found that Al metal can be electrodeposited from baths that were composed of 1,3-dimethyl-2-imidazolidinone (DMI) and AlCl3, with an AlCl3 concentration greater than 50 mol%. IR spectroscopy indicated that Al2Cl7− ions were present in the baths that contained >50 mol% AlCl3, where the electrodeposition of Al occurs from Al2Cl7− ion. The DMI/AlCl3 baths with AlCl3 concentrations between 59 and 64 mol% retained a single liquid phase without precipitation at 25°C, and therefore, they can be used for Al electrodeposition near room temperature. Smooth Al films could be obtained by galvanostatic electrodeposition at 40°C using a DMI/AlCl3 bath with the addition of a trace amount of 1,10-phenanthroline.

Optimization of the Electrodeposition Parameters to Improve the Stoichiometry of In2S3 Films for Solar Applications Using the Taguchi Method

Properties of electrodeposited semiconductor thin films are dependent upon the electrolyte composition, plating time, and temperature as well as the current density and the nature of the substrate. In this study, the influence of the electrodeposition parameters such as deposition voltage, deposition time, composition of solution, and deposition temperature upon the properties of In2S3 films was analyzed by the Taguchi Method. According to Taguchi analysis, the interaction between deposition voltage and deposition time was significant. Deposition voltage had the largest impact upon the stoichiometry of In2S3 films and deposition temperature had the least impact. The stoichiometric ratios between sulfur and indium (S/In: 3/2) obtained from experiments performed with optimized electrodeposition parameters were in agreement with predicted values from the Taguchi Method. The experiments were carried out according to Taguchi orthogonal array L27 (3∧4) design of experiments (DOE). Approximately 600 nm thick In2S3 films were electrodeposited from an organic bath (ethylene glycol‐based) containing indium chloride (InCl3), sodium chloride (NaCl), and sodium thiosulfate (Na2S2O3·5H2O), the latter used as an additional sulfur source along with elemental sulfur (S). An X‐ray diffractometer (XRD), energy dispersive X‐ray spectroscopy (EDS) unit, and scanning electron microscope (SEM) were, respectively, used to analyze the phases, elemental composition, and morphology of the electrodeposited In2S3 films.

Anodic Oxidation of Titanium in Mixture of β-Glycerophosphate (β-GP) and Calcium Acetate (CA)

Anodic oxidation is an electrochemical method for the production of a ceramic film on a metallic substrate. It involves the use of an electrical bias at relatively low currents while the substrate is immersed in a weak organic acid bath. The films produced are usually dense and stable, with variable microstructural features. In the present work, ceramic films of the anatase and rutile polymorphs of TiO2were formed on high-purity Ti foil (50 μm) using mixtures of β-glycerophosphate disodium salt pentahydrate (β-GP) and calcium acetate monohydrate (CA) solutions. The experiments were carried out at varying voltages (150-350 V), times (1-10 min), and current density (10 mA.cm-2) at room temperature. The ceramic films were characterised using digital photography, glancing angle X-ray diffraction (GAXRD), and field emission scanning electron microscopy (FESEM). The thicknesses of the films on Ti were measured using focused ion beam (FIB) milling. The colour, microstructures, and thicknesses of the films were seen to be strongly dependent on the applied voltage. At bias &lt;200 V, single-phase anatase was observed to form on Ti, while at higher bias (250 V), rutile formed due to the arcing process.

Unusual "chemical" mechanism of carbon co-deposition in Cr-C alloy electrodeposition process from trivalent chromium bath

Kinetics and mechanism of chromium-carbon alloy deposition process were investigated using trivalent chromium electroplating bath containing formic acid and carbamide (urea). The rate of carbon co-deposition process is determined by the rate of chromium electroplating reaction (electrochemical process of Cr-deposition imposes its own kinetics regularities on carbon co-deposition). It was supposed that a part of active chromium ad-atoms generated as a result of Cr(II) ions discharge may interact with adsorbed organic bath constituents by "chemical" mechanism.

Iron Aluminide Coatings by Electrodeposition of Aluminum from an Organic Bath and Subsequent Annealing

Iron Aluminide Coatings by Electrodeposition of Aluminum from an Organic Bath and Subsequent Annealing

Lipid vesicle adsorption on micropore arrays prepared by colloidal lithography-based deposition approaches

We present a new method for obtaining patches of fluid lipid membranes by patterning zinc oxide nanorods in 2D–3D micropore arrays via colloidal lithography combined with metal organic chemical vapour deposition and chemical bath deposition.