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排序方式: 共有1448条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(8):5638-5649
The sustainable reduction of greenhouse gas emissions from road transport requires solutions to achieve net-zero carbon dioxide emissions. Therefore, in addition to vehicles with electrified powertrains, such as those implemented in battery electric of fuel cell vehicles, internal combustion engines fueled with e-fuels or biofuels are also under discussion. An e-fuel that has come into focus recently, is hydrogen due to its potential to achieve zero tank-to-wheel and well-to-wheel carbon dioxide emissions when the electrolysis is powered by electricity from renewable sources. Due to the high laminar burning velocity, hydrogen has the potential for engine operation with high cylinder charge dilution by e.g. external exhaust gas recirculation or enleanment, resulting in increased efficiency. On the other hand, the high burning velocity and high adiabatic flame temperatures pose a challenge for engine cooling due to increased heat losses compared to conventional fuels. To further evaluate the use of hydrogen for small passenger car engines, a series production 1 L 3 cylinder gasoline engine provided by Ford Werke GmbH was modified for hydrogen direct injection. The engine was equipped with a high pressure external exhaust gas recirculation system to investigate charge dilution at stoichiometric operation. Due to limitations of the turbocharging system, very lean operation, which can achieve nitrogen oxides raw emissions below 10 ppm, was limited to part load operation below BMEP = 8 bar. Thus, a reduction of the nitrogen oxides emission level at high loads compared to stoichiometric operation was not possible. At stoichiometric operation with external exhaust gas recirculation engine efficiency can be increased significantly. The comparison of stoichiometric hydrogen and gasoline operation shows a reduced indicated efficiency with hydrogen with significant faster combustion of hydrogen at comparable centers of combustion. However, higher boost pressures would allow to achieve even higher indicated efficiencies by charge dilution compared to gasoline engine operation. 相似文献
2.
Global decrease in crude oil resources and frequent crude oil leaks cause the energy crisis and ecological pollution. The absorption and release of leaked crude oil through absorption materials are a necessary process for environmental protection and recycling. In this article, a CO2-responsive olefin copolymer was obtained by copolymerization of styrene and an amine-containing olefin monomer. The structure of resultant copolymer was characterized by FTIR; thermal properties and CO2-responsive morphology changes were determined by DSC/TGA and SEM, respectively. Copolymers had certain absorption capacity for toluene with absorption rate up to 180.0%. The absorbed toluene could be released upon CO2 stimulation with desorption rate up to 84.6%. The CO2-responsive copolymer could be regenerated through a simple heating process and showed stable absorption–desorption performance even after being recycled for 4 times. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47439. 相似文献
3.
The technology to produce compatibilized blends of liquid crystalline polymer and highly amorphous cyclic olefin copolymers through two novel approaches were studied. The first approach was to use silane-functionalized halloysite nanotube as nonspecific compatibilizer and the second method was reactive compatibilization. The study of blends and their resulting microstructure; their thermal, mechanical, and viscoelastic properties were investigated. The kinetic study of blends compatibilized through both routes was performed. 相似文献
4.
重整生成油选择性加氢脱烯烃 Pd基催化剂的研究 总被引:1,自引:0,他引:1
研究了负载在Al2O3载体上的贵金属钯(Pd)基催化剂在重整生成油选择性加氢脱烯烃反应中的性能。在高压微反装置上,采用环己烯、甲苯和正庚烷的混合物为模拟油来评价筛选催化剂,并对不同工业原料油进行加氢试验。结果表明,在现有工业上常用的工艺条件下,采用Pd/Al2O3催化剂进行重整生成油全馏分的选择性加氢,不能满足产品质量要求。其原因是高沸点馏分强吸附在催化剂表面,从而导致催化剂失活。在适宜的工艺条件下,采用Pd/Al2O3催化剂进行连续重整汽油BTX 馏分选择性加氢脱烯烃,可以使加氢汽油满足芳烃抽提进料的质量要求。添加助剂对Pd/Al2O3催化剂进行改进,可以大大提高催化剂的稳定性。改进后的双金属Pd基催化剂(Pd+M/Al2O3)可用于不同原料的重整生成油(苯(C6)馏分、BTX(C6~C9)馏分、全馏分)的选择性加氢脱烯烃反应。加氢反应产物的溴价小于200mgBr/100g,芳烃损失小于0.5%(质量分数),且在重整生成油全馏分的选择性加氢过程中该催化剂表现出好的稳定性。 相似文献
5.
分子筛绿色化合成技术的开发 总被引:3,自引:0,他引:3
对现有分子筛合成废液中氨氮及还原性物质的来源进行分析,确定降低排放废水中氨氮浓度及COD的方案。对现有ZRP-5分子筛制备流程进行优化,增加母液及赶胺水回用工序;建立母液浓缩装置,将钛硅分子筛及Β分子筛的合成母液及重排母液应用于ZSM-5分子筛的合成,实现废液的梯级利用。上述措施既解决了因分子筛生产废液的排放造成的环境污染,亦因废物资源化降低了ZSM-5分子筛的生产成本。 相似文献
6.
7.
介绍了利用现有的催化裂化装置 ,通过优化操作及运用MGD技术提高柴油和液化气收率的方法和技术措施。 相似文献
8.
9.
开发了一种用于脱除重整生成油或混合芳烃中烯烃的加氢精制催化剂TORH-1,该催化剂以具有独特孔道结构的新型氧化铝材料为载体,以Pd和Pt为主要活性组分。实验室中型试验、工业侧线试验、工业试验及工业应用结果表明,TORH-1催化剂具有良好的脱烯烃活性、选择性、稳定性以及对复杂原料的适应性,可以完全替代工业颗粒白土。TORH-1催化剂开工不需要额外预硫化,开工方法简便、安全和绿色环保。 相似文献
10.
MIP-CGP工艺专用催化剂CGP-1的开发与应用 总被引:11,自引:3,他引:8
阐述了生产汽油组分满足欧Ⅲ排放标准并多产丙烯的催化裂化工艺(简称MIP-CGP)专用催化剂(简称CGP-1)的研究开发与工业应用结果。CGP-1催化剂的基质具有良好的容炭性能,使活性组元受到良好保护,其优势作用在第二反应区得以充分发挥,具有更高的氢转移活性和强的汽油小分子烯烃裂化活性。中国石化九江分公司和镇海炼化公司的MIP-CGP工业试验标定结果表明,与常规FCC相比,采用CGP-1催化剂的MIP-CGP技术在生产烯烃体积分数小于18%的汽油组分的同时,丙烯产率达到8%以上。此外,汽油诱导期大幅提高,抗爆指数增加;总液体收率有所提高,干气产率下降,焦炭选择性良好。 相似文献