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1.
采用三维溶度参数理论并借助计算机软件模拟计算了防老剂4020、天然橡胶(NR)、顺丁橡胶(BR)和丁苯橡胶(SBR)的三维溶度参数值,分别计算了防老剂4020与NR、BR和SBR之间的Flory-Huggins相互作用参数(χ),并与防老剂4020的相容性实验结果进行对比,以预测防老剂与橡胶间的相容性。结果表明,三维溶度参数理论在表征防老剂4020与橡胶的相容性方面具有独特的优势,通过实验数据拟合,得到了防老剂4020的相容性与χ值之间的定量关系。 相似文献
2.
Vaidhegi Kugarajah Moogambigai Sugumar Elamathi Swaminathan Nagaraj Balasubramani Sangeetha Dharmalingam 《International Journal of Hydrogen Energy》2021,46(42):22134-22148
Hydrothermally prepared zinc oxide nanorods are sulphonated (S–ZnO NR) and incorporated into 15% Sulphonated Poly (1,4-Phenylene Ether Ether Sulfone) (SPEES) to improve the hydrophilicity, water uptake and ion transfer capacity. Water uptake and ion transfer capacity increased to 34.6 ± 0.6% and 2.0 ± 0.05 meq g?1 from 29.8 ± 0.3% and 1.4 ± 0.04 meq g?1 by adding 7.5 wt% S–ZnO NR to SPEES. Morphological studies show the prepared S–ZnO NR is well dispersed in the polymer matrix. SPEES +7.5 wt% S–ZnO NR membrane exhibits optimum performance after three-weeks of continual operation in a fabricated microbial fuel cell (MFC) to produce a maximum power density of 142 ± 1.2 mW m?2 with a reduced biofilm compared to plain SPEES (59 ± 0.8 mW m?2), unsulphonated filler incorporated SPEES (SPEES + 7.5 wt% ZnO, 68 ± 1.1 mW m?2) and Nafion (130 ± 1.5 mW m?2) thereby suggesting its suitability as a sustainable and improved cation exchange membrane (CEM) for MFCs. 相似文献
3.
Carina Heisig Jelka Diedenhoven Christopher Jensen Helmut Gehrke Thomas Turek 《化学工程与技术》2020,43(3):484-492
The conversion of bio-based succinic acid (SA) to the value-added chemicals 1,4-butanediol (BDO), γ-butyrolactone (GBL), and tetrahydrofuran (THF) can replace the corresponding petrochemical production routes to achieve a sustainable process. The reaction network for aqueous-phase catalytic hydrogenation of succinic acid over a supported Re-Pd catalyst was identified and the reaction kinetics was determined. With the developed kinetic model, the composition of the product mixture regarding the desired products (BDO, GBL, THF) can be described as a function of educt concentration, temperature, and pressure. The maximum BDO yield was achieved at high pressure and low temperature, while low pressure and high temperature favored GBL and THF production. 相似文献
4.
Identification of potential technologies for 1,4-Butanediol production using prospecting methodology
Ramon Geraldo Campos Silva Tatiana Felix Ferreira Élcio Ribeiro Borges 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(12):3057-3070
1,4-Butanediol (1,4-BDO) is a four-carbon diol used for industrial applications such as organic solvents, and the production of adhesives, fibers and polyurethanes. 1,4-BDO currently is produced through several petrochemical routes: hydrogenation of maleic anhydride, isomerization of propylene oxide, acetoxylation of butadiene, and the reaction between formaldehyde and acetylene. The current trends in 1,4-BDO production involve the utilization of renewable sources such as biomass. In this context, the present study aimed to identify promising technologies of 1,4-BDO production through prospecting methodology based on the analyses of patents and scientific article, describing the most relevant aspects of those emerging technologies. An increasing amount of 1,4-BDO production focused on biotechnological routes has been reported, with the US heavily involved in the development of new technologies. This study tracked three promising technologies which have potential for application in a biorefinery context because those processes involve (i) production of 1,4-BDO from sugars, classified herein as the biotechnological route; (ii) production of intermediates from sugar fermentation followed by catalytic conversion into 1,4-BDO, classified herein as the hybrid route, and (iii) furan/furfural conversion into 1,4-BDO. © 2020 Society of Chemical Industry 相似文献
5.
Functional expression and synergistic cooperation of xylan‐degrading enzymes from Hypocrea orientalis and Aspergillus niger 下载免费PDF全文
6.
采用等体积浸渍法制备了系列不同MgO含量的CuO-Bi2O3-MgO/γ-Al2O3催化剂,用N2-BET、XRD和TPR对其进行表征,并考察了其催化甲醛溶液和乙炔合成1,4-丁炔二醇的性能。结果表明,添加适量的MgO可显著改进催化剂的活性和选择性,其中γ-Al2O3先负载质量分数1%的MgO,700℃焙烧后,再共浸渍CuO和Bi2O3后500℃焙烧制备的30%CuO-2%Bi2O3-1%MgO/γ-Al2O3催化剂性能较好,1,4-丁炔二醇产率和选择性可分别达到67.9%和90.3%。 相似文献
7.
8.
在低酸度溶液中,以三嵌段非离子表面活性剂P123为模板剂,采用水热合成法制备锡掺杂PHTS催化剂(Sn-PHTS),采用XRD、TEM、N2吸附-脱附、NH3-TPD和FTIR等手段对其进行表征,并考察了Sn-PHTS催化1,4-丁二醇酯化的性能。结果表明,Sn-PHTS催化剂具有有序的六方晶相结构,随着锡含量的增加,其比表面积、孔容、孔径变化较小,酸性逐渐减小;在催化1,4-丁二醇和醋酸的酯化反应中,3Sn-PHTS表现出更高的催化活性,单酯收率达46.8%。 相似文献
9.
以氟苯和肉桂醇为起始原料,氟苯经傅克烷基化、水解、羰基还原和溴代得到双(4-氟苯基)溴甲烷,肉桂醇经氯代,再和哌嗪反应制得肉桂基哌嗪,然后与双(4-氟苯基)溴甲烷反应,最终制得产品。并做了重复性实验验证了稳定性。通过工艺条件的优化,确定合成盐酸氟桂利嗪的最佳工艺条件为:n(氟苯)∶n(AlCl3)∶n(PEG-400)=1∶1.1∶0.04,45℃反应2h,n(4,4'-二氟二苯甲酮)∶n(硼氢化钠)=1∶0.6,乙醇作溶剂,50℃保温2h,选择 NBS 作为4,4'-二氟二苯甲醇的溴代试剂,AIBN 做引发剂,物料比为 n(4,4'-二氟二苯甲醇)∶n(NBS)∶n(AIBN)=1∶1∶0.03,80℃反应3h,n(肉桂基氯)∶n(哌嗪)=1∶3.5,50℃保温1.5h,粗品肉桂基哌嗪通过水洗、萃取和成盐等步骤提纯,收率达56.2%。盐酸氟桂利嗪的总收率由18.5%提高到30.0%,产物纯度在99%以上。产物结构经红外和质谱进行了表征确定。 相似文献
10.
Carbon dioxide capture, utilization, and storage (CCUS) is one of the promising negative emission technologies (NET). Within various CCUS routes available, CO2 conversion into fuels is one of the attractive options. Currently, most of CO2 conversion into fuels requires hydrogen, which is expensive and consume large energy to produce. Hence, a different route of producing fuel from CO2 by utilizing 1,4‐butanediol as the raw material is proposed and evaluated in this study. This alternative route comprises production of levulinic acid from the reaction between CO2 and 1,4‐butanediol and production of ethyl levulinate, an alternative biofuel and biofuel additive, via an esterification reaction of levulinic acid with ethanol. The process is designed and simulated according to the available data and evaluated in terms of its technical features. Because of the unavailability of reaction data for synthesis of levulinic acid from 1,4‐butanediol and CO2, several assumptions were taken, which may implicate the accuracy of the studied design. This technical evaluation is followed by cost estimations and sensitivity analysis. Because of the free CO2, the profitability of the plant depends strongly on the prices of the other chemicals and the price difference between 1,4‐butanediol (raw material) and ethyl levulinate (product). Monte Carlo simulation indicates that the proposed plant will always be profitable if the ethyl levulinate is slightly more expensive than the 1,4‐butanediol, highlighting that the process of producing ethyl levulinate from CO2 is economically profitable. Future research should be directed towards a catalytic system that can effectively convert CO2 into levulinic acid, by‐products produced from the two reaction steps, and reduce the excess ethanol used in the second reaction. 相似文献