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1.
In the present study, we report an eco-friendly and simple route to design and synthesize novel nanocomposite catalyst based on platinum nanoparticles anchored on binary support of graphitic carbon nitride (g-C3N4) and cobalt-metal-organic framework (ZIF-67). For this purpose, ZIF-67 was prepared by precipitation method and g-C3N4 was prepared through thermal polymerization method. Later, ZIF-67 and g-C3N4 were hybridized through sonication to get homogeneous g–C3N4–ZIF-67 nanocomposite support material. Platinum nanoparticles (PtNPs) were uniformly deposited on g–C3N4–ZIF-67 by an electrochemical method. The as-developed nanocatalyst was characterized by morphological, structural and electrochemical techniques. The electrocatalytic activity of PtNPs@g–C3N4–ZIF-67 nanocatalyst towards butanol oxidation was evaluated via CV, CA, LSV and EIS in an alkaline medium. Results revealed that the proposed catalyst showed greatly enhanced electrooxidation of butanol in terms of high magnificent current density, lower oxidation potential, excellent long-term stability, large surface area, low charge transfer resistance and less toxic ability. Enhanced catalytic performance of the proposed catalyst could be ascribed to the synergistic effect of g–C3N4–ZIF-67 nanocomposite and PtNPs. The PtNPs@g–C3N4–ZIF-67 catalyst holds promising potential applications to be used as an anodic electrocatalyst for the development of high-performance alkaline fuel cells.  相似文献   
2.
In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space-time yield. Thermal separation is not feasible due to the boiling point of n-butanol. As an integrated and selective solid-liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed-bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once.  相似文献   
3.
The partition of n-butanol in Winsor type III (W-III) microemulsions was investigated in this work. Three kinds of anionic surfactants (sodium dodecyl sulfate (SDS), sodium dodecyl sulfonate (DSS), and sodium dodecyl benzene sulfonate (SDBS)) and two kinds of anionic/cationic surfactant mixtures (SDS/octadecyl trimethyl ammonium chloride (OTAC) mixtures and DSS/OTAC mixtures) were studied. Internal standard gas chromatography was employed in n-butanol content analysis. The results showed that no water exists in the excess oil (EO) phase and no oil exists in the excess water (EW) phase. For the W-III microemulsions obtained by salinity scanning, relatively constant n-butanol content in the EO (11–12 v%) and EW (1–4 v%) was found under different salinities. Accurate measurement of n-butanol content in each phase is important for those systems having low solubilization ability. For the W-III microemulsions prepared using SDS/OTAC surfactant mixture, the percentage of n-butanol distributed into the interfacial layer decreased while the fraction of n-butanol in the interfacial layer first increased sharply and then tended to be stable with the addition of n-butanol. For the different optimum W-III microemulsion systems tested, most of the surfactant-to-alcohol molar ratio data are near 1:3, but obvious deviation could be observed for some data. On the basis of the accurate measurement of n-butanol content in the EO and EW phases, the standard free energy, ΔG o→in * (T = 298.15 K) of n-butanol transferring from the EO phase to the interfacial region was calculated. The results show negative ΔG o→in * values. For microemulsions with the same components, n-butanol content is an important factor influencing the ΔG o→in * value, and a high absolute value of ΔG o→in * leads to high solubilization ability.  相似文献   
4.
Abstract

Butyl acetate is a versatile chemical due to its excellent solvency for polymers, resins, and oils. In this work, the butyl acetate synthesis was studied by the esterification of n-butanol with acetic acid using the commercial immobilized lipase Novozym® 435. The acetic acid and n-butanol concentrations have to be limited in the enzymatic synthesis of this ester due to the deleterious effects caused by these reagents on the enzyme. Three methods of acetic acid addition (single, stepwise and continuous addition) were investigated to minimize the acid concentration. A significant drop on acid conversion was observed in the presence of a higher concentration of the reagents when single or stepwise acid addition was used. However, a solvent-free system using a continuous addition of acetic acid favored butyl acetate synthesis, reaching a conversion of 84% at 60?°C, employing 5?wt% of enzyme and n-butanol/acetic acid final molar ratio equal to 1/1.  相似文献   
5.
Two alcohols, ethanol and butanol, with different water contents were evaluated for phospholipids (PL) sequential extraction from drum dried egg yolk flakes. It showed that butanol was more effective in extracting total yolk lipids compared to ethanol, but the PL in the extract had the same concentration as in the original yolk total lipid. The use of aqueous ethanol of 95 and 75% resulted in lipid extracts with higher PL concentration during the initial stages of the sequential extraction. When ethanol was further diluted to a concentration of 55%, the solvent lost its PL extraction ability, and the total lipid recovery also decreased dramatically. When both the PL purity and recovery were considered, 75% ethanol was the most effective aqueous alcohol for PL extraction and enrichment from the yolk flakes. In the first stage of extraction using such a solvent, 67% of the total PL in the original yolk was recovered in a lipid fraction with a PL purity of 75%. This study identified the optimal ethanol concentration for PL extraction from dried egg yolk. With this information, the best solid:solvent ratio can be designed to extract and enrich the polar lipids from lipid-bearing materials with known moisture content using a renewable or “green” solvent, ethanol.  相似文献   
6.
木质纤维原料制备燃料丁醇的研究进展   总被引:1,自引:0,他引:1  
丁醇作为一种重要的且具有极大潜力的新型生物燃料受到广泛重视。生物发酵法制备丁醇是通过产溶剂梭菌的厌氧发酵合成,即传统的丙酮-丁醇-乙醇(ABE)发酵,其可以降低对有限石油资源的消耗和依赖;而以玉米、糖蜜等淀粉质和糖质为原料发酵制备丁醇使得丁醇的原料成本升高,不利于丁醇未来的发展和产业化;木质纤维素是自然界中廉价且丰富的可再生资源,利用木质纤维原料制备丁醇成为研究热点之一。本文介绍了木质纤维原料的预处理、酶解及脱毒;重点归纳了近年来国内外对以木质纤维素为原料产丁醇菌种的选育研究进展,并概括了ABE发酵工艺中的调控技术进展;最后针对以木质纤维原料制备丁醇过程存在的问题提出可能的解决方向,以期为高效利用木质纤维素制备燃料丁醇提供新思路。  相似文献   
7.
以尼龙酸和丁醇为原料,浓硫酸为催化剂,环己烷为带水剂,合成出了3种尼龙酸二丁酯.以正丁醇和异丁醇为原料时反应速率最快,仲丁醇为原料时反应速率最慢.考察了反应的醇酸物质的量比对酯化反应的影响,n(醇)∶n(酸)=1.1∶1是最适宜的反应条件.测试了3种产品的性能,其中尼龙酸二正丁酯性能最佳,适合作为润滑油添加剂和耐寒型增塑剂.  相似文献   
8.
9.
Frank Lujaji  Akos Bereczky 《Fuel》2011,90(2):505-510
Emission problems associated with the use of fossil fuels have led to numerous research projects on the use of renewable fuels. The aim of this study is to evaluate the effects of blends containing croton mogalocarpus oil (CRO)-Butanol (BU) alcohol-diesel (D2) on engine performance, combustion, and emission characteristics. Samples investigated were 15%CRO-5%BU-80%D2, 10%CRO-10%BU-80%D2, and diesel fuel (D2) as a baseline. The density, viscosity, cetane number CN, and contents of carbon, hydrogen, and oxygen were measured according to ASTM standards. A four cylinder turbocharged direct injection (TDI) diesel engine was used for the tests. It was observed that brake specific energy consumption (BSEC) of blends was found to be high when compared with that of D2 fuel. Butanol containing blends show peak cylinder pressure and heat release rate comparable to that of D2 on higher engine loads. Carbon dioxide (CO2) and smoke emissions of the BU blends were lower in comparison to D2 fuel.  相似文献   
10.
Catalytic partial oxidation of isobutanol was investigated at various contact times and equivalence ratios for the purpose of H2 production. This reaction was studied using a γ-Al2O3 coated foam as a catalyst, as well as a similar foam with rhodium (Rh) added. The results show that little H2 is produced when the Rh is absent, whereas selectivities as high as 62.92% were achieved (80% is the theoretical maximum) with the noble metal present. The alumina catalyst also displays no complete combustion regime for fuel lean combustion; instead, olefins, carbon dioxide (CO2), and water are the dominant products at all equivalence ratios. Additional results from catalytic partial oxidation of isobutene suggest that isobutene could be an intermediate during catalytic partial oxidation of isobutanol. With approximately 8.25 W of isobutanol, 3.61 W of H2 can be attained with the Rh catalyst for use in small power devices, such as a proton exchange membrane fuel cell. The corresponding fuel-to-electricity efficiency was about 20.8%.  相似文献   
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