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The structural details, viscosity trends and dynamic phenomena in t-butanol/water solutions are closely related on the molecular scales across the entire composition range. Utilizing ...the experimental small- and wide-angle x-ray scattering (SWAXS) method, molecular dynamics (MD) simulations and the ‘complemented-system approach’ method developed in our group it is possible to comprehensively describe the structure-viscosity-dynamics relationship in such structurally versatile hydrogen-bonded molecular liquids, as well as in similar, self-assembling systems with pronounced molecular and supramolecular structures at the intra-, inter-, and supra-molecular scales.
The SWAXS and x–ray diffraction experiments and MD simulations were performed for aqueous t-butanol solutions at 25 °C. Literature viscosity and self-diffusion data were also used.
The interpretive power of the proposed scheme was demonstrated by the extensive and diverse results obtained for aqueous t–butanol solutions across the whole concentration range. Four composition ranges with qualitatively different structures and viscosity trends were revealed. The experimental and calculated zero-shear viscosities and molecular self-diffusion coefficients were successfully related to the corresponding structural details. The hydrogen bonds that were, along with hydrophobic effects, recognized as the most important driving force for the formation of t–butanol aggregates, show intriguing lifetime trends and thermodynamic properties of their formation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The component proportion of gasoline varies depending on the mining time of crude oil, the mining place, and so on. Because it has effects on the engine performance and emission characteristics, ...studying the effects of the fuel properties on combustion characteristics is important. And a study of power generation for small gasoline engine by using alcohol fuel is extremely important from the viewpoint of stable power supply in the event of a disaster. These points, this experiment has been conducted to examine the reduction of combustion products of power generation for small gasoline engine by using standard fuel with Iso-Octane and Toluene in wide open throttle and throttle opening 2/3, especially about the effects of fuel properties by changing the addition ratio of 1-Butanol, 2-Butanol, Isobutanol, and t-Butanol with a high addition range. The main conclusions are as follows: 1) Standard fuel with Iso-Octane and Toluene is sufficiently possible to use as a alternative standard fuel of power generation for small gasoline engine. 2) It is possible to reduce CO and HC emissions remarkably compared with gasoline by addition of 1-Butanol, 2-Butanol, Isobutanol, and t-Butanol. 3) The CO and HC emissions of 1-Butanol can be reduced more than 31.6 % and 17.5 %, respectively compared with 2-Butanol, Isobutanol, and t-Butanol in the no- and low/medium load ranges. 4) 1-Butanol is most effective for reduction of combustion products when adding each of 1-Butanol, 2-Butanol, Isobutanol, and t-Butanol to standard fuel. 5) It is possible to control CO emissions at a low level, and the reduction of HC and NOx emissions can accomplish by controlling the addition ratio of 1-Butanol in the medium/high load range.
The enzymatic production of biodiesel by methanolysis of cottonseed oil was studied using immobilized
Candida antarctica lipase as catalyst in
t-butanol solvent. Methyl ester production and ...triacylglycerol disappearance were followed by HPLC chromatography. It was found, using a batch system, that enzyme inhibition caused by undissolved methanol was eliminated by adding
t-butanol to the reaction medium, which also gave a noticeable increase of reaction rate and ester yield. The effect of
t-butanol, methanol concentration and temperature on this system was determined. A methanolysis yield of 97% was observed after 24
h at 50
°C with a reaction mixture containing 32.5%
t-butanol, 13.5% methanol, 54% oil and 0.017
g enzyme (g oil)
−1. With the same mixture, a 95% ester yield was obtained using a one step fixed bed continuous reactor with a flow rate of 9.6
ml
h
−1 (g enzyme)
−1. Experiments with the continuous reactor over 500
h did not show any appreciable decrease in ester yields.
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The morphology of cross-linked polymers plays an important role in their physical and chemical properties. NMR cryoporometry allows for the investigation of these structures over ...different length scales, through appropriate choice of probe liquid. The different structures of two different polymeric samples, one a cross-linked polymer hydrogel, the other a pore-expanded ion-exchange polymer, are analysed here. The ability for NMR cryoporometry to analyse both polymeric materials in the swollen state is successfully demonstrated, as is the importance of probe-liquid choice for the analysis of different regions of the pore structure. In both cases, water is used to identify populations of pores smaller than ca. 5 nm. The use of t-butanol and menthol reveals the presence of additional mesoporous structures in the ion-exchange resin as well as the responsiveness of the pore structure to the liquid used to swell it.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Dimethyl Carbonate was explored as organic phase for the first time in three phase partitioning.•Parameters; salts, solvents, ratio of aqueous to organic, time, pH and temperature ...were optimised.•Peroxidase from bitter gourd waste with 4.89 fold purity and 177% recovery was obtained by TPP.•Bitter gourd peroxidase was successfully employed to degrade methylene blue dye.
Three phase partitioning (TPP) is most renowned technique used for extraction and purification of natural products. In previous studies of TPP, t-butanol is mainly used as an organic phase. This is the first report that explores ability of dimethyl carbonate (DMC) in the field of TPP as an alternate solvent for t-butanol. In the present study TPP process with t-butanol and DMC as organic phase along with different salts was applied to waste bitter gourd powder to obtained peroxidase enzyme. DMC was found to be compatible with most of salts such as ammonium sulphate and sodium citrate and explored as more efficient solvent than t-butanol. This TPP system provides 4.84 fold purity of peroxidase enzyme at optimum source concentration of 0.15g/mL, with a system comprising DMC as organic phase, sodium citrate (20%) as salt, agitation speed 120rpm, pH 7, temperature 30°C and extraction time of 3h. Present study has aimed for extraction and separation of peroxidase from bitter gourd waste with TPP technique and ensures the scope of carbonated solvents in extraction and purification of proteins.
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•t-Butanol was selected as an excellent freeze-drying medium for freeze-drying.•Higher SSA based on t-butanol medium than water was achieved.•GCT-based counter electrodes exhibited excellent ...electrocatalytic activity.•PCE increased to 8.70% from 7.05% under assisted by t-butanol as solvent.
Cryogels are typically synthesized using a freeze-drying method based on hydrogels. However, we have found that the volume changes of water during the freeze-drying process can destroy the gel structure. In this paper, t-butanol was selected as an excellent freeze-drying medium because of its favorable properties and retention of the massive gel structure. The graphene/single-walled carbon nanotube (SWCNT) cryogel exhibited a higher specific surface area (SSA) using t-butanol as a solvent (GCT) compared with using water (GCW) in the hydrogel for freeze-drying. GCT retained the most porous structure with the highest SSA (402.19m2·g−1) after the freeze-drying process. Then, GCW and GCT were tested as counter electrode materials as a substitute for platinized FTO in dye-sensitized solar cells (DSSCs). The DSSC based on the GCT counter electrode exhibited a remarkable photovoltaic conversion efficiency (8.70%) compared with the GCW-based CE (7.05%) and Pt (7.57%). Hence, our results demonstrate that graphene/SWCNT cryogels freeze-dried with t-butanol as the solvent are promising candidates for use in Pt-free DSSCs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Nuclear magnetic resonance (NMR) cryoporometry, although well established, can be limited by the inability of any one liquid to probe a broad range of pore sizes, a relatively small number of ...commonly-used probe liquids and the requirement to match the probe liquid to the chemistry of the material being studied. Here we demonstrate, for the first time, the use of menthol and t-butanol as probe liquids in NMR cryoporometry measurements. Using appropriate estimates for the values of the melting point depression constant, kc, and the non-freezing surface layer, 2sl, NMR melting data was converted into pore size distributions. The melting point depression constant for t-butanol is similar to that of cyclohexane; however due to its functionality, t-butanol may be the preferred liquid used to study the porosity of hydrophilic materials. Menthol, having a larger value of kc, can accurately analyze larger pore sizes up to 100 nm. This represents the first use of menthol and t-butanol to accurately probe pore dimensions in NMR cryoporometry.
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•Potential liquids for NMR cryoporometry expanded to include menthol and t-butanol.•Reliable estimates of parameters, kc and 2sl, obtained for both liquids.•Demonstration of use for both liquids over range of pore sizes from 20 to 100 nm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Ozonation of p-nitrophenol was carried out at constant pH values of 2, 7 and 10.•Radical scavenger t-butanol was used for different t-butanol concentrations.•pH determines the relative production ...rates of the first intermediates.•Radicals play an important role in ozonation at low pH.•There exists t-butanol concentration for the slowest 4-nitrocathecol production.
Ozonation of p-nitrophenol solution was carried out without pH control and at constant pH values of 2, 7 and 10. The effect of radical scavenger t-butanol at pH 2 was studied for t-butanol concentrations of 0.0, 0.000225, 0.00225 and 0.0225mol/dm3. The ozone decomposition rate was computed for each pH as a function of time on the basis of each experimental run. The consumed ozone dose was calculated at each pH and at each t-butanol concentration at pH 2. The results indicate that pH determines the relative production rates of the first intermediates, hydroquinone and 4-nitrocathecol, on the reaction path of p-nitrophenol decomposition and that radicals play an important role in ozonation at low pH. The results also indicate that there exists some optimum t-butanol concentration at which slowest 4-nitrocathecol production occurs, and further, there exists some optimum t-butanol concentration for highest consumed ozone dose per amount of decomposed p-nitrophenol at pH 2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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