Ethanol-water Mixed Solvent Research Articles

Coliquefaction of Lignite and Corn Stalk in Ethanol–Water Mixed Solvent with Addition of Formic Acid and Iron Ore Catalyst

The coliquefaction of Xilinguole lignite (XL) and corn stalk (CS) was carried out in water, ethanol, and ethanol–water mixed solvent at different mixing ratios with or without iron ore as catalyst, under initial N2 atmosphere. Results showed that ethanol improved the liquefaction and coliquefaction of XL and CS. The liquefaction of XL and CS separately resulted in 31.0 and 41.9 wt % of oil yield in ethanol and 7.3 and 20.2 wt % of oil yield in water, respectively, whereas the ethanol and water coliquefaction process resulted in 34.4 and 13.2 wt % of oil yield, respectively. The addition of formic acid increased the oil yield in the single liquefaction of XL and CS and their coliquefaction in ethanol, water, or ethanol–water (50:50, v/v). The liquefaction of XL and CS and coliquefaction of XL/CS in ethanol at N2 atmosphere with formic acid resulted in higher oil and conversion yields, suggesting that formic acid can supply active hydrogen. Also, iron ore was an effective catalyst, for instance, adding 20 w...

Liquefaction of sewage sludge in ethanol-water mixed solvents for bio-oil and biochar products

Liquefaction of sewage sludge (SS) is a promising technology for the preparation of bio-oil (target product) and biochar (by-product). The liquefaction of SS in ethanol-water cosolvent were preliminarily investigated in this study. There existed synergetic effects between ethanol and water on the liquefaction of SS. Higher bio-oil yield (33.5–36.1 wt%) were obtained in ethanol-water cosolvent, compared to those in pure water (32.2 wt%) and pure ethanol (26.8 wt%). Furthermore, the bio-oil obtained in ethanol-water cosolvent contained higher content of ester components, suggesting higher bio-oil quality. The addition of Na2CO3 further increased the yield of bio-oil (37.5 wt% versus 34.9 wt%), but lowered the quality of bio-oil. The main two types of coke oils in bio-oils were diesel oils and lubricating oils. Elemental, proximate and micromorphology analyses of biochars further indicated that ethanol-water cosolvent had better degradation/transformation effects on SS. The biochars obtained from the liquefaction of SS in ethanol-water cosolvent possessed similar specific surface area (23.0–26.0 m2/g) and pore volume (0.118–0.141 cm3/g) to SS pyrolysis biochar. In view of the yield and quality of liquefaction products, ethanol-water cosolvent may be more proper for the liquefaction of SS, compared to pure water/ethanol.

Nanostructured Zirconium Pyrophosphate Catalyzed Diastereoselective Synthesis of β-Amino Ketones via One-Pot Three-Component Mannich Reaction

In this study, ZrP2O7 catalytic nanomaterials were prepared by co-precipitation and polyvinylpyrrolidone assisted methods. These nanomaterials were structurally characterized by XRD, N2 adsorption/desorption, TGA, SEM and TEM microscopy techniques. This study investigated the application of these nanomaterials in the synthesis of various β-amino carbonyls via a one-pot-three-component condensation of aldehydes, ketones and amines. As a result, high efficiency was obtained in a water–ethanol mixed solvent at room temperature. Under the optimized conditions, the catalyst prepared via the PVP assisted method exhibited higher catalytic activity and higher diastereoselectivity when compared to the catalyst prepared by co-precipitation. Moreover, the ZrP2O7 catalysts were easily recovered and reused several times with only a slight loss of activity. At the conclusion of this study, a possible mechanism of the Mannich reaction over ZrP2O7 catalysts was also proposed and discussed.

Effect of Mixed Valence States of Platinum Ion Dopants on the Photocatalytic Activity of Titanium Dioxide under Visible Light Irradiation

Titanium dioxide doped with the Pt ion (Pt–TiO2) was synthesized by a sol–gel method using only water as the solvent and conducting dialysis. The photocatalytic activity for the degradation of 4-chlorophenol (4-CP) on Pt–TiO2 was not affected by the Brunauer–Emmett–Teller specific surface area under visible light (VL) irradiation. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure measurements revealed that only the Pt(IV) ion existed in the TiO2 bulk and both Pt(II) and Pt(IV) were present near the Pt–TiO2 surface. Pt(IV) is most likely substituted in the Ti(IV) site of the TiO2 lattice because of their similar ionic sizes. Quantitative analysis of Pt(II) was performed in the XPS measurements, indicating that the amount of Pt(II) on the surface increased with an increase in the doping amount from 0.2 to 1.0 atom %. We synthesized 0.5 atom % Pt–TiO2 with various Pt(II)/Pt(IV) ratios by changing the Ti(OC3H7)4 concentration used in the sol–gel synthesis. The 4-CP conversion on Pt–TiO2 increased linearly with an increase in the Pt(II)/Pt(IV) ratios. A similar relationship was obtained with Pt–TiO2, which was prepared by a conventional sol–gel method in ethanol–water mixed solvent. Therefore, the Pt(II)/Pt(IV) ratio is a key factor affecting the photocatalytic activity of Pt–TiO2 under VL irradiation. Our results indicate that controlling the mixed valence states of the doped metal ions is a new strategy to developing highly active metal-ion-doped TiO2 under VL irradiation.

Self-assembled monolayers of sulfonate-terminated alkanethiols investigated by frequency modulation atomic force microscopy in liquid

A molecular-scale understanding of self-assembled monolayers (SAMs) of sulfonate-terminated alkanethiols is crucial for interfacial studies of functionalized SAMs and their various applications. However, such an understanding has been difficult to achieve because of the lack of direct information on these molecular-scale structures in real space. In this study, we investigated the structures of sulfonate SAMs of sodium 11-mercapto-1-undecanesulfonate (MUS) by frequency modulation atomic force microscopy (FM-AFM) in liquid. The subnanometer-resolution FM-AFM images showed that the single-component MUS SAM prepared in pure water had random surface structures. In contrast, the MUS SAM prepared in a water–ethanol mixed solvent showed periodic striped structures with a flat-lying conformation. The results suggest a significant solvent effect on molecular-scale structures of long-chain sulfonate SAMs. In addition, we investigated the molecular-scale structures of mixed SAMs of MUS and 11-mercapto-1-undecanol (MUO) with alkane chains of the same length. The FM-AFM images of the mixed SAMs showed clear phase separation between MUS SAM and MUO SAM domains. In the MUO SAM domains, the incorporated MUS molecules appeared as protrusions. The results obtained in this study provide direct structural information on long-chain sulfonate and mixed SAMs.

Ultrasound assisted extraction of anthocyanins and total phenolic compounds from dried cob of purple waxy corn using response surface methodology

Ultrasound-assisted extraction of anthocyanins and total phenolic compounds from the dried cob of purple waxy corn was investigated using response surface methodology, where the process variables were ultrasound amplitude levels (25, 50, 100%) and different solvents (pure water, water–ethanol ratio 1:1, pure ethanol), using a sample–solvent ratio of 1:20, and extraction temperature of 65 °C for 30 min. Central composite face-centered design was used to determine optimum process conditions. The results showed that the overall optimal condition for simultaneous extraction of anthocyanins and phenolic compounds was obtained by using 50% water in water–ethanol mixed solvent as solvent and amplitude level of 50%. The optimal yields of anthocyanins and phenolic compounds were 240.161 μg cyanidin-3-glucoside/g dry sample and 27.662 mg gallic acid/g dry sample, respectively. The result for the antioxidant activity of the extract obtained from this optimal extraction condition to decrease the initial DPPH• concentration by 50% was approximately 4.64 mg/ml. Practical applications This article has practical application to study extraction of total anthocyanins and total phenolic compounds from dried cob of purple waxy corn using ultrasound-assisted extraction. The response surface method using central composite face-centered design was successfully employed to predict the effect of two independent variables on the ultrasound assisted extraction of total anthocyanins and total phenolic compounds. Moreover, the methodology and results presented in this study could be beneficial for future efforts to increase the recovery of potentially bioactive compounds from fruits, vegetables, plants and agricultural residues.

Facile synthesis of flower-like hierarchical architecture of SnO2 nanoarrays

A novel structure of flower-like hierarchical SnO2 architecture consisted of nanorods array was successfully synthesized by facile one-step hydrothermal route only using sodium stannate tetrahydrate solution of ethanol–water mixed solvent. The morphology and microstructure of the hierarchical SnO2 architecture showed that flower-like hierarchical SnO2 architecture with six similar petals were organized by large scale uniformity and ordered dense nanorods arrays with a diameter of 10–15 nm and length of about 200 nm. Infrared absorption spectra (IR), Raman spectra and Ultraviolet–visible (UV–vis) absorption spectra were carried out to investigate the optical properties of the flower-like hierarchical SnO2 nanoarrays. The UV–vis spectrum of as-prepared layered SnO2 nanorod array assemblies showed the band gap blue-shifted compared with the band gap of bulk SnO2. A series of peculiar emission band positions of the room temperature photoluminescence properties of the hierarchical SnO2 nanoarrays were observed.

Continuous Crystallization with Impurity Complexation and Nanofiltration Recycle

For crystal-impurity systems with similar structures and molecular weights, the impurity has a strong tendency to incorporate into the crystal lattice, making it difficult to obtain high purity with a single crystallization or even multiple crystallizations. In such cases, complexation of the impurity with an additive can be used to sterically prevent impurity incorporation in the host lattice. A nanofiltration membrane can be used to preferentially reject the higher molecular weight impurity complex in solution, while allowing the lower molecular weight API to permeate through. This permeate stream can be concentrated and recycled to operate the crystallization in a continuous mode with the aim of enhancing both yield and crystal purity simultaneously. In the present work, this strategy was applied to the continuous cooling crystallization of two systems in a mixed-suspension mixed-product removal (MSMPR) crystallizer from their solutions in 50:50 (by volume) water–ethanol mixed solvent. The first system...

Synthesis of N-doped Carbon Spheres Using Extended Stöber Method for SO2Adsorption

SO2is one of the major pollutants in the atmosphere. N-doped microporous carbon spheres (NCS) have been demonstrated to be effective for SO2adsorption. Here we report the synthesis of monodispersed NCS by the extended Stöber method with urea resorcinol-formaldehyde resins as carbon source, urea as nitrogen source and ammonia as catalyst in an ethanol-water mixed solvent. The obtained carbon spheres show a uniform diameter of around 550[Formula: see text]nm, specific surface area of 476[Formula: see text]m2[Formula: see text]g[Formula: see text], micropores pore volume of 0.20[Formula: see text]cm3[Formula: see text]g[Formula: see text] and nitrogen doping. The NCS manifest special performance for SO2capture with capability of 75.34[Formula: see text]mg[Formula: see text]g[Formula: see text] and good cycling stability, due to the large surface area, abundant micropores and nitrogen functionality.

Constructing a “Pizza‐Like” MoS2/Polypyrrole/Polyaniline Ternary Architecture with High Energy Density and Superior Cycling Stability for Supercapacitors

Polypyrrole (PPy) and polyaniline (PANI) are most promising candidates for high energy and power density supercapacitors. However, their relative low surface area and poor cyclic stability greatly limit their practical applications. Morphology‐ and size‐controlled micro/nanostructure formation of such materials may lead to enhanced performance. Here, the solvent‐exchange method is proposed for the preparation of high‐concentration few‐layer MoS2 (f‐MoS2) suspension in an ethanol–water mixed solvent. PPy layers with high surface coverage are formed on the resultant dispersible f‐MoS2 by in situ polymerization of pyrrole. The MoS2/PPy hybrid is then used as the reactive layer for subsequent in situ growth and attachment of PANI, thus forming a “pizza‐like” MoS2/PPy/PANI ternary nanostructure. The rational design of such hierarchical nanostructures greatly enhances the specific capacitance up to 1273 F g−1 at 0.5 A g−1 and effectively improves the cyclic performance maintaining ≈83% after 3000 charge/discharge cycles. The excellent performances of MoS2/PPy/PANI hybrid are mainly attributed to robust interconnected frameworks for improved electrical conductivity and well‐defined porosities for enhanced electrolyte/electrode interaction. The superior electrochemical performance thus suggests a promising strategy for fabricating component adjustable, high energy density, and durable nanostructures as novel electrode materials for supercapacitors.

Examination of the dyeing properties of pigment printing fabrics in a water-ethanol mixed solvent

We examined the dyeing properties of pigment printing fabrics in a water-ethanol mixed solvent. SEM, infrared spectroscopy, XRD, and rheological studies were carried out to understand the results. The K/S values of all pigment printing fabrics initially increased prior to a subsequent decrease, as can be observed from SEM images of the fabric surfaces. Viscosity tests indicated that variations in the dyeing performance in the mixed solvent could be mainly attributed to the quality of the thickener. Through examination of the rheological properties of the NaAlg paste and the IR spectra of the NaAlg membrane, ethanol appeared to weaken the hydrogen bonds between the NaAlg chains and water molecules, leading to more compact and disordered NaAlg chains. As the rubbing fastness remained relatively constant upon increasing the colour depth of the printing fabrics, this indicated the potential for broadening the application range of such a system.

Solvothermal synthesis of 3D leaf-like α-Fe2O3 and its gas-sensing properties research

3D leaf-like Alpha-iron oxide (α-Fe2O3) nanostructure and other nanomorphologies were fabricated by adding different ethanol content in ethanol-water mixed solvent under a simple solvothermal route. The structures and morphologies of nanostructures were characterized by X-ray diffraction (XRD), field-emission electron scanning microscopy (FESEM) and transmission electron microscopy (TEM). Their morphologies and gas-sensing properties were mainly studied. The sensor synthesized in 80vol% ethanol–water as the solvent exhibited lower operating temperature (260°C), higher response and shorter Response/recovery time (about 8s and 9s). The results indicated that 3D leaf-like iron oxide (α-Fe2O3) nanostructure was a potential candidate for fabricating effective acetone sensor.

Fabrication of Z-scheme Ag3PO4/MoS2 composites with enhanced photocatalytic activity and stability for organic pollutant degradation

In this study, highly efficient visible-light-driven Ag3PO4/MoS2 composite photocatalysts with different weight ratios of MoS2 were prepared via the ethanol-water mixed solvents precipitation method and characterized by ICP, XRD, HRTEM, FE-SEM, BET, XPS, UV–vis DRS and PL analysis. Under visible-light irradiation, Ag3PO4/MoS2 composites exhibit excellent photocatalytic activity towards the degradation of organic pollutants in aqueous solution. The optimal composite with 0.648wt% MoS2 content exhibits the highest photocatalytic activity, which can degrade almost all MB under visible-light irradiation within 60min. Recycling experiments confirmed that the Ag3PO4/MoS2 catalysts had superior cycle performance and stability. The photocatalytic activity enhancement of Ag3PO4/MoS2 photocatalysts can be mainly ascribed to the efficient separation of photogenerated charge carriers and the stronger oxidation and reduction ability through a Z-scheme system composed of Ag3PO4, Ag and MoS2, in which Ag particles act as the charge separation center. The high photocatalytic stability is due to the successful inhibition of the photocorrosion of Ag3PO4 by transferring the photogenerated electrons of Ag3PO4 to MoS2. The evidence of the Z-scheme photocatalytic mechanism of the composite photocatalysts could be obtained from the active species trapping experiments and the photoluminescence technique.

Synthesis, growth, spectral, optical and thermal properties of a novel metal–organic family single crystal: Bis (thiocyanato) cobalt(II) di thiourea

Single crystals of bis(thiocyanato) cobalt(II) di thiourea [Co(NCS)2(N2H4CS)2]; BTCT were grown from an aqueous solution using slow evaporation technique for the first time. Interestingly, Co2+ ion present in the crystalline compound connects two N atoms of thiocyanate and four S atoms of thiourea ligands. The bridging thiourea ligands link Co ions into a one dimensional polymeric chain along [100] direction. Single crystal XRD shows that the BTCT crystal belongs to triclinic system with the space group P1¯. BTCT single crystals were subjected to FT-IR, Laser Raman, UV–vis, CHNS, TG-DTA and DSC studies. The optical study shows that the UV cut-off wavelength of BTCT in ethanol–water mixed solvent is about 310nm. The thermal analysis of BTCT reveals that the sample is thermally stable up to 196.01°C. The VSM study shows that Co2+ in BTCT possesses higher coercivity (32.414μCi) and retentivity (654.62E-6emu/g) than Mn2+ of [Hg(N2H4CS)4Mn(SCN)4]; TMTM.

Unique nanocrystalline frameworks in mesoporous tin phosphate prepared through a hydrofluoric acid assisted chemical reaction

A mesostructured tin phosphate (SnPi) material has been prepared in the presence of an amphiphilic block copolymer (F127), tin chloride (SnCl4), and phosphoric acid (H3PO4) in an ethanol–water mixed solvent medium.

Use of the Pitzer model for correlating thermodynamic phase behavior of salts in water–ethanol mixed solvent solutions

Hydrogen can be produced from Ethanol through many industrial processes which may involve electrolyte species in some cases. The thermodynamic phase behavior of electrolyte solutions is very important for the design of such processes.The Pitzer model, initially designed for aqueous electrolyte solutions, has been adapted to the case of electrolytes in mixed solvent solutions. This approach was applied for calculating activity coefficients of the electrolytes KCl, CsCl, NaCl and NaBr in water–ethanol mixtures at 25 °C. The Pitzer parameters have been evaluated for each salt in both aqueous and ethanol–water mixed solvent by minimizing the objective function using experimental data from literature.The values of the standard deviations show that the Pitzer model can be used successfully in modeling activity coefficients of the electrolytes studied in both aqueous and ethanol-water mixed solvent solutions.

Controlled synthesis of α-Fe2O3 nanostructures for efficient photocatalysis

α-Fe2O3 microspheres and nanospheres were successfully fabricated by a simple solvothermal method in ethanol–water mixed solvent, with the assistance of NaCl and NaBr, respectively. The as-prepared sample was characterized by XRD, FESEM, TEM, BET surface area, and UV–vis diffuse reflectance spectra. The photocatalytic activity of the α-Fe2O3 nanostructures was evaluated by photocatalytic degradation of Rhodamine B under visible-light irradiation. The results show that α-Fe2O3 nanospheres prepared in the presence of NaBr exhibit much better photocatalytic activity than α-Fe2O3 microspheres prepared in the presence of NaCl. The good photocatalytic activity of α-Fe2O3 nanospheres is attributed to the larger surface area and enhanced light absorption.

Sonochemical synthesis of monodispersed perovskite barium zirconate (BaZrO3) by using an ethanol–water mixed solvent

Perovskite barium zirconate (BaZrO3) was synthesized successfully in an ethanol–water mixed solvent under ultrasonic irradiation. Four compositions, including 0%, 30%, 50%, and 70% by volume of ethanol in ethanol/water mixed solvent, were used. The effect of ethanol content and irradiation time on the phase formation and morphology of product particles was studied and discussed. As a result, a pure perovskite BaZrO3 phase was formed completely at a short irradiation time of about 15min in 70% by volume of ethanol without the calcination process. The average particles size decreases and particle size distribution becomes narrower by increasing the percentage of ethanol volume. On the other hand, the monodispersibility of BaZrO3 particles was improved significantly through ultrasonic irradiation.

In situ IR spectral identification of NH4H2PO4structural evolution during crystallization in water–ethanol mixed solvent

Download options Please wait... Supplementary files Supplementary information PDF (643K) Article information DOI https://doi.org/10.1039/C5CE00196J Article type Paper Submitted 28 Jan 2015 Accepted 02 Mar 2015 First published 02 Mar 2015 Download Citation CrystEngComm, 2015,17, 2728-2736 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions In situ IR spectral identification of NH4H2PO4 structural evolution during crystallization in water–ethanol mixed solvent C. Sun and D. Xue, CrystEngComm, 2015, 17, 2728 DOI: 10.1039/C5CE00196J To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Congting Sun Dongfeng Xue

Growth, crystalline perfection, spectral and optical characterization of a novel optical material: l-tryptophan p-nitrophenol trisolvate single crystal

l-tryptophan p-nitrophenol trisolvate (LTPN), an organic nonlinear optical material was synthesized using ethanol–water mixed solvent and the crystals were grown by a slow solvent evaporation method. The crystal structure and morphology were studied by single crystal X-ray diffraction analysis. The crystalline perfection of the LTPN crystal was analyzed by high-resolution X-ray diffraction study. The molecular structure of the crystal was confirmed by observing the various characteristic functional groups of the material using vibrational spectroscopy. The cut-off wavelength, optical transmission, refractive index and band gap energy were determined using UV–visible data. The variation of refractive index with wavelength shows the normal behavior. The second harmonic generation of the crystal was confirmed and the efficiency was measured using Kurtz Perry powder method. Single and multiple shot methods were employed to measure surface laser damage of the crystal. The photoluminescence spectral study revealed that the emission may be associated with the radiative recombination of trapped electrons and holes. Microhardness measurements revealed that LTPN belongs to a soft material category.