Showing papers in "Journal of Chemical & Engineering Data in 2018"
TL;DR: The presented DESs show good potential to be used as CO2 capture agents and are similar to those found in renowned fluorinated ILs, while the heats of CO2 absorption are in the range of nonpolar solvents.
Abstract: The solubility of CO2 in hydrophobic deep eutectic solvents (DESs) has been measured for the first time. Six different hydrophobic DESs are studied in the temperature range from 298 to 323 K and at CO2 pressures up to 2 MPa. The results are evaluated by comparing the solubility data with existing hydrophilic DESs and currently applied physical solvents and fluorinated ionic liquids. The DESs are prepared by mixing decanoic acid with a quaternary ammonium salt with different halide anions and alkyl chain lengths. The measured CO2 solubilities are similar to those found in renowned fluorinated ILs, while the heats of CO2 absorption are in the range of nonpolar solvents. The presented DESs show good potential to be used as CO2 capture agents.
113 citations
TL;DR: In this article, 15 different types of amine and glycol-based deep eutectic solvents were synthesized and investigated for CO2 absorption, and the highest CO2 solubility was observed for the tetrabutyl ammonium bromide and methyldiethanol amine (TBAB/4MDEA).
Abstract: Anthropogenic CO2 emissions into the atmosphere are responsible for the global warming, therefore, it is essential to reduce these emissions at the source. Recently, deep eutectic solvents (DESs) have shown great potential to absorb the CO2. In the current study, 15 different types of amine- and glycol-based deep eutectic solvents were synthesized and investigated for CO2 absorption. In general, amine-based solvents have shown higher CO2 absorption as compared to glycol based solvents. In particular, the highest CO2 absorption was observed for the tetrabutyl ammonium bromide and methyldiethanol amine (TBAB/4MDEA) system having a CO2 solubility of 0.29 (mol CO2/mol solvent) at 1 MPa and 303.15 K. Thermophysical properties of all synthesized DESs were estimated using the modified Lydersen–Joback–Reid method and Lee–Kesler mixing rule. Experimental CO2 solubility data were well fitted using the nonrandom two liquid and the Peng–Robinson thermodynamic models. Apart, CO2 solubility data were correlated with He...
101 citations
TL;DR: In this paper, the performance of fluoride adsorption on a specific tetrametallic oxide adsorbent Fe-Al-Ce-Ni (FACN) and the effect of temperature on adaption performance was investigated.
Abstract: This study investigated the performance of fluoride adsorption onto a specific tetrametallic oxide adsorbent Fe–Al–Ce-Ni (FACN) and the effect of temperature on adsorption performance. The adsorption performance was determined by adsorption equilibrium, kinetics, and thermodynamic parameters. The adsorption, kinetic, and thermodynamic parameters were compared alternatively. The fluoride adsorption capacity was obtained from four different adsorption isotherm models, namely, Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich (D–R), and Freundlich was found to best fit model. Fluoride removal rate using adsorption (0.27 min–1) was obtained faster than reactive adsorption (0.04 min–1). Several thermodynamic parameters such as enthalpy, Gibbs free energy, entropy (ΔS > 0), and adsorption activation energy were calculated which demonstrated the feasibility and spontaneity (ΔG < 0) and exothermic nature of (ΔH < 0) the fluoride adsorption process. The adsorption process was controlled by a physical mechanis...
99 citations
TL;DR: In this article, an amine-functionalized magnetic chitosan (AFMCS) composite beads were used for the remediation of nitrate and phosphate in batch scale.
Abstract: A variety of adsorbent materials have been tried day by day to minimize the effects of blue baby syndrome and eutrophication but most of them constitute academic interest because of their properties such as powder form, poor selectivity, not easily separable, and difficult regeneration; hence, they could not be used at field conditions. To overcome such technological bottle-necks, the present study has been carried out with amine-functionalized magnetic chitosan (AFMCS) composite beads which was prepared and applied for the remediation of nitrate and phosphate in batch scale. The fabricated adsorbent materials were characterized by Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller analysis, transmission electron microscopy, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray analysis with mapping analysis. The numerous adsorption-influenced parameters such as contact time, adsorbent dosage, initial ions concentration, co-anions, solution pH, and temperature were opti...
78 citations
TL;DR: In this article, the authors report the high absorption properties of the DES based on 1-butyl-3-methyl imidazolium methanesulfonate-urea toward ammonia.
Abstract: The concept of eutectic solvents as a platform technology for a variety of applications including gas separation has become a popular approach. To date, the number of known deep eutectic solvents (DESs) is limited mainly to halide salts easily interacting with a hydrogen-bond donor (HBD) and resulting in the formation of a liquid phase. Actually, the DESs properties may be tuned by selecting the appropriate HBD, while the structure of the anion is not a decisive factor. However, the presence of other anions may be favorable for certain applications; therefore, expanding the range of deep eutectic solvents seems a relevant issue of chemistry and material science. In this study, we report the high absorption properties of the DES based on 1-butyl-3-methyl imidazolium methanesulfonate–urea toward ammonia. The structure features investigations have revealed the major contribution of C(2)-H to hydrogen bonding. To assess the possibility of selective separation, the solubility of ammonia and two acidic gases (H...
73 citations
TL;DR: In this paper, the adsorptive removal of atrazine, an agricultural herbicide, from water by three water stable MOFs, ZIF-8, UiO-66, and UIO-67, and a commercial activated carbon, F400, was investigated.
Abstract: The adsorptive removal of atrazine, an agricultural herbicide, from water by three water stable MOFs, ZIF-8, UiO-66, and UiO-67, and a commercial activated carbon, F400, was investigated. UiO-67, ZIF-8, and F400 were found to remove up to 98% of the atrazine from water, whereas UiO-66 is found to be ineffective. In an exceptional performance compared to the other adsorbents considered in our study, UiO-67 removed 98% of atrazine from water within only 2 min, whereas ZIF-8 and F400 took over 40 and 50 min, respectively, to remove the same amount of atrazine. Upon regeneration of UiO-67, minimal loss of adsorption capacity was observed, affirming its effective use for atrazine removal from water.
60 citations
TL;DR: In this article, hierarchical porous carbon nanospheres were synthesized by a hydrothermal process at 130 °C/24 h using different triblock copolymers such as F108 (PEO133PPO50PEO 133; PEO, poly(ethylene oxide); PPO, poly (propylene oxide)), F127 (PPO70PEO106), and L64 (PIO13PPO30PEO13) as soft templating agents.
Abstract: Hierarchical porous carbon nanospheres were synthesized by a hydrothermal process at 130 °C/24 h using different triblock copolymers such as F108 (PEO133PPO50PEO133; PEO, poly(ethylene oxide); PPO, poly(propylene oxide)), F127 (PEO106PPO70PEO106), and L64 (PEO13PPO30PEO13) as soft templating agents. Characterization of the samples was carried out by low angle XRD, Raman spectra, FESEM, TEM, and N2 adsorption–desorption studies. The BET surface area of the samples was in the range 600–750 m2/g comprised of micropores and mesopores. Nanospherical particles of size range 60–100 nm were formed. The synthesized samples were used for the removal of phenol and methylene blue (MB), the toxic organic contaminant in water. The maximum adsorptions of 98.9 and 100% were observed within 10 min for phenol and MB, respectively. For different soft templates, the adsorption capacity of the samples followed in the order CF108 > CF127 > CL64, which was affected by the textural properties of the corresponding samples. Select...
55 citations
TL;DR: In order to better understand the hydrate-based desalination process, experiments have been conducted using cyclopentane hydrates, which can be formed at atmospheric pressure and temperatures below 7.7 °C as discussed by the authors.
Abstract: The use of a hydrate-based technology in seawater desalination is an interesting potential hydrate application since salt ions would be excluded from the hydrate crystal lattice. In order to better understand the hydrate-based desalination process, experiments have been conducted using cyclopentane (CyC5, sII) hydrates, which can be formed at atmospheric pressure and temperatures below 7.7 °C. The hydrate formation experiments were performed at various subcoolings for aqueous solutions with different salinities in a bubble column. The hydrate formation times decreased and the hydrate conversion increased with increasing subcooling and agitation. Various hydrate-former injection methods were studied, with the most effective method involving spraying finely dispersed CyC5 droplets (around 5 μm in diameter) into the water-filled bubble column. The latter method resulted in a 2-fold increase in seawater conversion to hydrate crystals compared with injecting millimeter-scale CyC5 droplets. A desalination effic...
54 citations
TL;DR: In this article, the authors evaluated biorenewable deep eutectic solvents (DES) composed of glycerol (Gly) and choline chloride (ChCl) for citrus essential oil deterpenation.
Abstract: Citrus essential oils are complex hydrocarbon mixtures mainly composed of terpenes and terpenoids and are widely used as raw materials in food, pharmaceutical, and fine chemical industries. However, essential oil deterpenation (i.e., separation of terpenes and terpenoids) is required to preserve the quality of the final product for practical applications. Currently, there is a need to find efficient and environmentally friendly solvents to replace the harmful volatile organic compounds that are conventionally used as extraction solvents. Therefore, alternative solvents with more benign and environmentally friendly characteristics are crucial to develop sustainable citrus essential oil deterpenation processes. In this work, biorenewable deep eutectic solvents (DES) composed of glycerol (Gly) and choline chloride (ChCl) are evaluated as sustainable solvents for citrus essential oil deterpenation, using model mixtures and real citrus crude orange essential oils (COEO). The liquid–liquid extraction process fo...
51 citations
TL;DR: In this paper, the saturation pressure of trifluoroethene (R1123, CF2═CHF) and 3,3,3-trifluoropropene (R1243zf, CF3CH═CH2) were measured by the isochoric method for temperatures between 278 and 377 K. The experimental uncertainties in temperature and pressure are estimated to be 5 mK and 1 kPa (k = 2), respectively.
Abstract: Saturation pressures for new low global warming potential refrigerants trifluoroethene (R1123, CF2═CHF) and 3,3,3-trifluoropropene (R1243zf, CF3CH═CH2) were measured by the isochoric method for temperatures between 278 and 377 K. Temperature was measured with a 25 Ω standard platinum resistance thermometer on ITS-90. Pressure was measured with a digital quartz pressure transducer. The experimental uncertainties in temperature and pressure are estimated to be 5 mK and 1 kPa (k = 2), respectively. New saturation-pressure correlations for the refrigerants have been formulated based on the present saturation-pressure data. The critical pressures of R1123 and R1243zf were also determined.
47 citations
TL;DR: In this paper, a series of deep eutectic solvents (DESs) based on benzyltrimethylammonium chloride and benzyltributylammoniamium chloride as hydrogen bond acceptor (HBAs) with three ethylene glycols and glycerols as HBDs were investigated.
Abstract: Deep eutectic solvents (DESs) are regarded as a promising and emerging alternative for volatile organic compounds (VOCs) due to their cost-effectiveness and environmentally sustainable nature. Formulation of new DESs and thorough investigation of their physicochemical properties have been on the rise ever since potential applications of DES have been realized. The present study reports a new series of DES based on benzyltrimethylammonium chloride and benzyltributylammonium chloride as hydrogen bond acceptor (HBAs) with three ethylene glycols and glycerols as hydrogen bond donors (HBDs). The current work includes the synthesis, characterization, and investigation of the thermophysical properties of a series of DES systems. The studied properties include density, ρ, speed of sound, u, viscosity, η, refractive index, nD, and electrical conductivity, σ, for all DESs in the temperature range from 283.15 to 343.15 K. The observed trends in properties like density, speed of sound, viscosity, and refractive indic...
TL;DR: In this paper, the authors present an extensive literature survey and analysis of the heat capacity and thermodynamic properties of fusion, vaporization, and sublimation for the linear hydrocarbons and several terminally substituted homologous series.
Abstract: The present work presents an extensive literature survey and analysis of the heat capacity and thermodynamic properties of fusion, vaporization, and sublimation for the linear hydrocarbons and several terminally substituted homologous series. The successive introduction of methylene groups on the relative stability of the solid and liquid phases is analyzed and discussed based on the chain length dependence of the enthalpies, entropies, and Gibbs energies of phase transition. An odd–even alternation is observed in the fusion and sublimation equilibria. The improved packing patterns of even-numbered n-alkanes is reflected in higher values of melting temperatures and thermodynamic properties of phase transition. Molar heat capacities in liquid phase of n-alkanes derivatives exhibit a linear dependence with the chain length by an increment of 31 ± 2 J·K–1·mol–1 per methylene group (−CH2−). A contribution of 4.95 kJ·mol–1 per methylene group (value corrected for 298.15 K) is derived for the increment of the e...
TL;DR: The results demonstrate that α-amino acids with similar physical structures have similar changes in solubility in mixed water/ethanol mixtures.
Abstract: The addition of organic solvents to α-amino acids in aqueous solution could be an effective method in crystallization We reviewed the available data on the solubility of α-amino acids in water, water–ethanol mixtures, and ethanol at 29815 K and 01 MPa The solubility of l-alanine, l-proline, l-arginine, l-cysteine, and l-lysine in water and ethanol mixtures and the solubility of l-alanine, l-proline, l-arginine, l-cysteine, l-lysine, l-asparagine, l-glutamine, l-histidine, and l-leucine in pure ethanol systems were measured and are published here for the first time The impact on the solubility of amino acids that can convert in solution, l-glutamic acid and l-cysteine, was studied At lower concentrations, only the ninhydrin method and the ultraperfomance liquid chromatography (UPLC) method yield reliable results In the case of α-amino acids that convert in solution, only the UPLC method was able to discern between the different α-amino acids and yields reliable results Our results demonstrate that
TL;DR: In this article, the process of palladium(II) chloride complex ion adsorption on activated carbon was investigated and the influence of variable parameters such as the initial concentration of the PdII complex and temperature (from 294 to 348 K) was determined.
Abstract: The process of palladium(II) chloride complex ion adsorption on activated carbon was investigated The influence of variable parameters such as the initial concentration of the Pd(II) complex (from 004 to 225 mmol·kg–1) and temperature (from 294 to 348 K) was determined Experiments were conducted in the solution with pH equal to 0 and 1 It was found that the Freundlich adsorption isotherm describes the process better than the Langmuir model The observed sorption capacity as high as q294K = 424 mg·g–1 and q323K = 67 mg·g–1 for activated carbon was found at 294 and 323 K, and it is increasing with temperature increase The obtained results showed that the palladium(II) complex may react with functional groups present on the surface of activated carbon The thermodynamic parameters such as the equilibrium constant and heat and entropy of adsorption were derived The enthalpy value is equal to −67 kJ·mol–1, and the entropy is equal to −23 J·mol–1·K–1 It is suggested that, during chemisorption of palla
TL;DR: In this paper, the effects of tetra-n-butyl ammonium bromide (TBAB) and graphite nanoparticles (GN) on phase equilibrium curves, gas consumption, induction time, and ratio of water to hydrate conversion were investigated.
Abstract: The effects of tetra-n-butyl ammonium bromide (TBAB) and graphite nanoparticles (GN) on phase equilibrium curves, gas consumption, induction time, and ratio of water to hydrate conversion were investigated in this work. Aqueous solutions of the mixture of TBAB and GN with three concentrations of 0.04%, 0.06%, 0.08%, and 0.1% were tested in a stirred reactor. The graphite nanoparticles with a concentration of 0.08% showed the highest hydrate formation rate, revealing that 0.08% is the optimal concentration for the hydrate formation in this study. Comparing the induction time of the pure TBAB system with that of various concentrations of GN, a decrease by 16.6% of induction time at 0.08% GN concentration was observed, while the value decreased by 31.62% at a GN concentration of 0.1%. The final water to hydrate conversion reached the maximum value of 50.75% at a GN concentration of 0.08%. The concentration effect of graphite nanoparticles on the phase equilibrium curve in the presence of TBAB was also studie...
TL;DR: In this article, the authors reported the isosteric heat of adsorption on pure carbon dioxide on zeolite 13X (also called zeolites NaX) pellets over a temperature range of 0 to 200 °C and a pressure range from 0.001 to 100 kPa.
Abstract: Adsorption isotherms are reported for pure carbon dioxide on zeolite 13X (also called zeolite NaX) pellets over a temperature range of 0 to 200 °C and a pressure range of 0.001 to 100 kPa. These pure-component equilibria are fit with Langmuir, Toth, two-site Langmuir, and three-site Langmuir models, both with and without temperature dependence being included in the saturation capacity. The agreement between fitted and measured isotherms is shown to increase with increasing number of available fitting parameters in the model, with the constant-saturation, two-site Langmuir isotherm providing the best balance between agreement with the measurements and model complexity. The isosteric heats of adsorption are measured across a temperature range from 10 to 200 °C using differential scanning calorimetry. The measured heats of adsorption decrease with increasing CO2 loading but show little variation with temperature. The measurements are shown to agree with predicted heats of adsorption derived from the fitted L...
TL;DR: The experimental results showed that the mole fraction solubility of florfenicol in the pure solvents decreased according to the following order: ethanol > 1-propanol > 2-pro-panol, 2-methyl-1-hexanol > 3-methyl 1-butanol > 2.5 methyl 1hexanol as mentioned in this paper.
Abstract: The solubility of florfenicol form A in eight pure organic solvents (propionic acid, ethanol, 1-propanol, 1-butanol, 2-propanol, 2-methyl-1-propanol, 3-methyl-1-butanol, and 2-ethyl-1-hexanol) and three binary solvents (dimethyl sulfoxide + ethanol, dimethyl sulfoxide + 1-propanol, and dimethyl sulfoxide + 1-butanol) was measured by a laser dynamic method at temperature from 283.15 to 323.15 K. The experimental results show that the mole fraction solubility of florfenicol in the pure solvents decreased according to the following order: ethanol > 1-propanol > 2-propanol > 1-butanol > 3-methyl-1-butanol > 2-methyl-1-propanol ≈ propionic acid > 2-ethyl-1-hexanol. The experimental results show that the mole fraction solubility of florfenicol form A in the binary solvents increased with the increase of temperature and dimethyl sulfoxide mass fraction. The experimental solubility data were well correlated with the four thermodynamic models: modified Apelblat equation, λh equation, NRTL model equation, and Wilso...
TL;DR: In this article, the physicochemical effects present in five binary liquid mixtures containing n-butyl acetate + a homologue series of 1-alkanols have been studied over the full range of concentrations by measuring the density and viscosity at temperatures 29315 to 32315 K.
Abstract: Physico-chemical effects present in five binary liquid mixtures containing n-butyl acetate + a homologue series of 1-alkanols have been studied over the full range of concentrations by measuring the density and viscosity at temperatures 29315 to 32315 K The alcohols considered are those from 1-hexanol up to 1-decanol Excess molar volumes are positive for all binary mixtures over the whole concentration range, while viscosity deviations are negative for all binary systems Influences of temperature and addition of −CH2 group of alcohols on excess properties have been discussed Systems involving n-butyl acetate + 1-alkanol are mainly characterized by the self-association of the alcohol, and the mentioned effect decreases when the size of the 1-alkanol increases in the mixtures As a result, molecular interactions are weaker in longer 1-alkanols Moreover, the applicability of PC-SAFT theory has been examined and discussed for these systems Although the PC-SAFT model provides consistent results on the
TL;DR: In this article, the suitability of different combinations of property data among vapor pressure, enthalpy of vaporization, and saturated-liquid heat capacity (cP,liqsat) data for fitting consistent Twu α-function parameters is evaluated.
Abstract: The suitability of different combinations of property data among vapor-pressure (Psat), enthalpy of vaporization (ΔvapH) and saturated-liquid heat-capacity (cP,liqsat) data for fitting consistent Twu α-function parameters is evaluated. A given combination is declared to be suitable if the obtained fitted parameters produce acceptable predictions for the three considered properties for the 783 molecules included in the reference database. Calculations are carried out using the translated-consistent versions of the Peng–Robinson (tc-PR) and Redlich–Kwong (tc-RK) cubic equations of state (CEoS). It is demonstrated that reliable parameters are obtained on the condition that they are, at least, fitted to vapor-pressure data. It is strongly advised to not exclusively fit α-function parameters to enthalpy of vaporization and/or saturated-liquid heat capacity data. Finally, Twu α-function parameters (L, M, N) suitable for the tc-PR and tc-RK CEoS are determined for the 1721 molecules, for which at least accurate ...
TL;DR: In this paper, four natural deep eutectic solvents (NADES) were prepared at specific molar ratios, La:Bet (2:1), La:Hist (9:1) (lactic acid/histidine), Ma:Bet:H2O (1:2:3) (malic acid/betaine/water) and Ma: Bet:Pro:H 2O ( 1:1:1):2)
Abstract: In this paper, four natural deep eutectic solvents (NADES) systems were prepared at specific molar ratios, La:Bet (2:1) (lactic acid/betaine), La:Hist (9:1) (lactic acid/histidine), Ma:Bet:H2O (1:2:3) (malic acid/betaine/water) and Ma:Bet:Pro:H2O (1:1:1:2) (malic acid/betaine/proline/water). Their physical and thermodynamic properties were studied, namely viscosity, electrical conductivity, and heat capacity. The viscosity and electrical conductivity were determined as a function of temperature and the correlation for the temperature dependence was obtained and discussed based on Arrhenius theory. The heat capacity for all eutectic systems was measured by differential scanning calorimetry (DSC) over a temperature range of 293.15–363.15 K. The ability of these NADES to reduce cellulose crystallinity was evaluated. Cellulose crystallinity after suspension in these NADES was studied by X-ray diffraction. Cellulose suspended in Ma/Bet/H2O (1:2:3) suffer the highest crystallinity reduction among the systems st...
TL;DR: A very low interfacial tension, γ, can be achieved between an oil phase and an aqueous solution containing anionic surfactant and salt at a very low concentration in the presence of monovalent [sodium chloride, NaCl] and divalent [calcium chloride, CaCl2] salts in the low concentration range as mentioned in this paper.
Abstract: A very low interfacial tension, γ, can be achieved between an oil phase and an aqueous solution containing anionic surfactant and salt at a very low concentration. This phenomenon can have potential applications in recovering residual oil from the reservoir through low salinity–low surfactant enhanced oil recovery flooding. Measurements of γ between n-heptane and aqueous solution of anionic surfactants in the concentration range of 0.141–2.167 mM and salts in the concentration range of 9.010–119.780 mM at 313.15 ± 0.1 K have been carried out. The experimental results show that the value of γ falls to a lowest value at a temperature above the Krafft point when the concentration of anionic surfactants [sodium dodecyl sulfate (SDS) and dioctyl sulfosuccinate sodium salt (AOT)] is increased up to a maximum surface excess concentration in an aqueous solution in the presence of monovalent [sodium chloride, (NaCl)] and divalent [calcium chloride, (CaCl2)] salts in the low concentration range. To understand and a...
TL;DR: In this paper, the capability of DESs containing other salts (e.g., different alkyl chain lengths or different functional groups on the ammonium cation) for the extraction of thiophene from n-hexane + THiophene mixtures via LLE was evaluated.
Abstract: In a previous work, we proved that the deep eutectic solvents (DESs) consisting of mixtures of tetraalkylammonium salts with polyols are promising candidates for oil desulfurization based on the obtained liquid–liquid equilibrium (LLE) data. In this study, the capability of DESs containing other salts (e.g., different alkyl chain lengths or different functional groups on the ammonium cation) for the extraction of thiophene from {n-hexane + thiophene} mixtures via LLE was evaluated. Therefore, four DESs composed of tetraethylammonium chloride or methyltriphenylphosphonium bromide as hydrogen bond acceptors and ethylene glycol or glycerol as hydrogen bond donors were prepared. Thereafter, the binary solubilities of the aliphatic hydrocarbon (n-hexane) and the thiophene in DESs were measured at 298.2 K and atmospheric pressure. Next, ternary liquid–liquid equilibrium (LLE) data for the four ternary systems {n-hexane + thiophene + DES} were measured at 298.2 K and atmospheric pressure. The conductor-like scre...
TL;DR: A phytic acid impregnated polyaniline (PA-PANI) was synthesized by a in situ polymerization and supermolecular self-assembly method and has been used as an adsorbent for efficient capture of.
Abstract: A novel phytic acid impregnated polyaniline (PA-PANI) was synthesized by a in situ polymerization and supermolecular self-assembly method and has been used as an adsorbent for efficient capture of
TL;DR: In this article, the aggregation behavior in binary mixtures of two surfactants, 1-hexadecyl-3methylimidazolium chloride and dodecyltrimethylammonium bromide, has been investigated in aqueous solutions using condu...
Abstract: The aggregation behavior in binary mixtures of two surfactants, 1-hexadecyl-3-methylimidazolium chloride and dodecyltrimethylammonium bromide, has been investigated in aqueous solutions using condu...
TL;DR: A novel magnetic nanomaterial based on Fe3O4-g-C3N4 was synthesized by a facile ultrasonic method and characterized by various means, including scanning ele....
Abstract: A novel magnetic nanomaterial (Fe3O4-g-C3N4) based on Fe3O4 nanoparticles anchored on g-C3N4 was synthesized by a facile ultrasonic method and characterized by various means, including scanning ele...
TL;DR: In this paper, a carboxymethyl cellulose adsorbent (TCMC) was synthesized by the oxidation reaction of carboxy methyl cellulose with sodium periodate followed by a condensation reaction with thiosemicarbazide and stabilized with sodium borohydride, which was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermogravimetric analyzer (TGA), and Fourier transform infrared spectroscopy (FTIR).
Abstract: Thiosemicarbazide-modified carboxymethyl cellulose adsorbent (TCMC) was synthesized by the oxidation reaction of carboxymethyl cellulose with sodium periodate followed by a condensation reaction with thiosemicarbazide and stabilized with sodium borohydride. TCMC was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermogravimetric analyzer (TGA), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). FTIR and XPS analysis successfully shows inclusion of the sulfur and Cu(II) adsorption mechanism onto TCMC. It was also confirmed that the maximum adsorption of Cu(II) ions was achieved by the presence of NH2, OH, and COOH groups. The effects of aldehyde content, pH, time, and concentration of Cu(II) ions were analyzed. Kinetics and error analysis suggested that the pseudo-second-order was best fitted for the adsorption of Cu(II) ions than the other models. The maximum Cu(II) ion adsorption was obtained by the Langmuir model i...
TL;DR: In this paper, measurements of PvT properties, saturated densities, and critical parameters were carried out for a low-GWP refrigerant: 3,3,3-trifluoropropene (HFO1243zf, CF3CH═CH2).
Abstract: Measurements of PvT properties, saturated densities, and critical parameters were carried out for a low-GWP refrigerant: 3,3,3-trifluoropropene (HFO1243zf, CF3CH═CH2). Seventy-five PvT property dat...
TL;DR: In this paper, the synthesis of Mg/Al-CO3 layered double hydroxides (LDHs) by the urea hydrolysis method under hydrothermal conditions at different aging times was reported.
Abstract: Herein, we report the synthesis of Mg/Al-CO3 layered double hydroxides (LDHs) by the urea hydrolysis method under hydrothermal conditions at different aging times. The LDHs were characterized by different microscopic, spectroscopic, diffractometric, and thermal analysis techniques. The as-prepared LDHs were then used as adsorbents for the removal of fluoride ions from water. The adsorption process was systematically studied in terms of influences of pH, interaction time, temperature, adsorbent loading, fluoride ion concentration, and the effect of coexisting anions to understand the ideal conditions for adsorption. The adsorption process primarily followed pseudo-second-order kinetics. The Langmuir monolayer adsorption capacities of different adsorbents are in the range of 15.13–27.03 mg g–1 at 303 K. The hydrothermal aging time has a negative impact on the adsorption capacities of the LDHs. The as-prepared LDHs are reusable up to five cycles of the fluoride ion adsorption–desorption process.
TL;DR: In this article, the solubility data of CO2 in four azole-based deep eutectic solvents (DESs), prepared from azoles (imidazole, Im; 1,2,4-triazoles,Tri) and acetylcholine chloride (ACC), were reported at temperatures of 303.15, 313.15 and 333.15 K under a pressure range of (20.0-600.0) kPa using the isochoric saturation method.
Abstract: The solubility data of CO2 in four azole-based deep eutectic solvents (DESs), prepared from azoles (imidazole, Im; 1,2,4-triazole,Tri) and acetylcholine chloride (ACC), were reported at temperatures of 303.15, 313.15, 323.15, and 333.15 K under a pressure range of (20.0- 600.0) kPa using the isochoric saturation method. Henry’s constants and thermodynamic properties of standard Gibbs free energy, enthalpy, and entropy changes of CO2 dissolution were derived by correlating the data. Results demonstrated that ACC-Im DESs (Hm = 1.91–4.46 MPa·kg·mol–1) possess higher capacities of CO2 than CC-Tri ones (Hm = 2.66- 4.58 MPa·kg·mol–1). The CO2 solubility increased with rising pressure, mole ratio of Im to ACC, and decreasing temperature. All the obtained enthalpies of solution were negative. Furthermore, the comparison of dissolution capacities between present DESs and other DESs as well as some ionic liquids in the literature was conducted.
TL;DR: Graphene oxide loaded with titanium dioxide composites (GO-TiO2) was successfully prepared by hydrolysis of titanium tetrachloride in the presence of an aqueous dispersion of graphene oxide, and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrography (XPS), transmission electron microscope (TEM), and X -ray diffraction (XRD) as mentioned in this paper.
Abstract: Graphene oxide loaded with titanium dioxide composites (GO-TiO2) was successfully prepared by hydrolysis of titanium tetrachloride in the presence of an aqueous dispersion of graphene oxide, and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and X-ray diffraction (XRD). Characterized results exhibited that TiO2 was successfully loaded on the surface of GO. Adsorptive removal of tetracycline (TC) by GO-TiO2 and photocatalytic regeneration of adsorbent was investigated. Adsorption isotherms of TC onto GO-TiO2 proved that the adsorption process was multilayered, and the adsorption capacity of GO-TiO2 for aqueous TC in the tested range was 99.46, 117.98, and 133.05 mg/g at 15, 25, and 35 °C, respectively. TC adsorption by GO-TiO2 followed the pseudo-second-order kinetic model. TC adsorption by GO-TiO2 was favored at lower pH and decreased with an increase of solution pH. Additionally, Ca2+ had a more powerful in...