【摘 要】
:
Copper-based catalysts were widely used in the heterogeneous selective hydrogenation of ethylene car-bonate (EC),a key step in the indirect conversion of CO2 to methanol.However,a high H2/EC molar ratio in feed is required to achieve favorable activity an
【机 构】
:
Key Laboratory for Green Chemical Technology of Ministry of Education,Collaborative Innovation Cente
论文部分内容阅读
Copper-based catalysts were widely used in the heterogeneous selective hydrogenation of ethylene car-bonate (EC),a key step in the indirect conversion of CO2 to methanol.However,a high H2/EC molar ratio in feed is required to achieve favorable activity and the methanol selectivity still needs to be improved.Herein,we fabricated a series of Pt-modulated Cu/SiO2 catalysts and investigated their catalytic perfor-mance for hydrogenation of EC in a fixed bed reactor.By modulating the Pt amount,the optimal 0.2Pt-Cu/SiO2 catalyst exhibited the highest catalytic performance with ~99% EC conversion,over 98% selectiv-ity to ethylene glycol and 95.8% selectivity to methanol at the H2/EC ratio as low as 60 in feed.In addition,0.2Pt-Cu/SiO2 catalyst showed excellent stability for 150 h on stream over different H2/EC ratios of 180-40.It is demonstrated a proper amount of Pt could significantly lower the H2/EC molar ratio,promote the reducibility and dispersion of copper,and also enhance surface density of Cu+ species.This could be due to the strong interaction of Cu and Pt induced by formation of alloyed Pt single atoms on the Cu lattice.Meanwhile,a relatively higher amount of Pt would deteriorate the catalytic activity,which could be due to the surface coverage and aggregation of active species.These findings may enlighten some fundamen-tal insights for further design of Cu-based catalysts for the hydrogenation of carbon-oxygen bonds.
其他文献
Developing highly efficient,durable,and non-noble electrocatalysts for the sluggish anodic oxygen evo-lution reaction (OER) is the pivotal for meeting the practical demand in water splitting.However,the cur-rent transition-metal electrocatalysts still suf
目的 提高新任护士长综合管理病区的能力,同时缓解工作压力,以饱满的热情投身护理管理中.方法 选取该院新任护士长5人实施改良型“AB角模式”培养,即由2名科护士长以上的护理管理骨干(A、B角)先后对其进行目标性指导带教,每人指导时间3个月,A角、B角分别指导后的第3个月从护理质量、患者满意度调查结果、院回访中心回访结果、护理不良事件、上级部门指令性任务完成情况等多维度进行权重计算、评价,并调查其工作压力情况,与2018年度新上任护士长同期进行对比.结果 实施改良型“AB角模式”培养后的新任护士长病区综合管理
现代科技支撑下的医疗设备是实现优质医疗成果的重要技术保障,不可替代.全面提升医疗设备的可靠性、安全性与有效性,不仅取决于医疗设备的质量品质,更与医疗设备使用人员的日常操作、医疗设备的维护保养、故障维修等环节密切相关.西藏地区自然环境恶劣、交通不便、人力资源缺乏,医疗设备安全使用保障问题尤为突出.该文针对日喀则市人民医院医疗设备使用及管理过程中存在的问题,充分梳理现有制度、流程,完成管理流程的再造,逐步构建医院医疗设备安全使用精细化管理体系.医疗设备安全使用精细化管理体系的建立并严格执行实施过程中,充分借鉴
目的 探讨血站实行绩效考核对提升血站整体管理水平的作用.方法 以茂名市中心血站绩效考核的实际做法和效果为例,分析实行绩效考核对推动血站健康发展的作用.结果 员工工作积极性和主动性提高,采供血量持续增长,血液供需稳定平衡,无偿献血工作得到健康、稳定、持续发展.结论 科学合理的绩效考核管理能发挥导向、激励和控制作用,使收入分配更科学、更公平,促进血站和员工个人的进步,实现效率提高和质量提升,确保质量管理体系的贯彻落实和临床用血供应.
The nature and distribution of Cu species in Cu-SSZ-13 play a vital role in selective catalytic reduction of NO by NH3 (NH3-SCR),but existing methods for adjusting the Cu distribution are complex and difficult to control.Herein,we report a simple and effe
Mordenite (MOR) has shown great potential to catalyze dimethyl ether (DME) carbonylation to methyl acetate (MA) in industry.The synergy between metal species and Brφnsted acid sites accelerates DME conversion.Here we designed and prepared two catalysts wi
Fischer-Tropsch synthesis (FTS) wax is a mixture of linear hydrocarbons with carbon number from C7 to C70+.Converting FTS wax into high-quality diesel (no sulfur and nitrogen contents) by hydrocracking technology is attractive in economy and practicabilit
为进一步提高涂覆水性环氧树脂的45钢在重防腐蚀领域的防腐蚀能力,研究纳米ZrO2含量对水性环氧树脂复合涂层防腐蚀性能的影响规律,采用硅烷偶联剂KH550和钛酸酯偶联剂HY105分别改性纳米ZrO2,并将不同含量的2种改性纳米ZrO2添加至环氧树脂制成复合涂料涂覆在45钢表面,通过极化曲线和电化学阻抗谱研究涂层的防腐蚀性能,用扫描电镜(SEM)观察涂层的表面形貌.结果 表明:硅烷偶联剂和钛酸酯偶联剂改性后的纳米ZrO2均可有效提高水性环氧涂层的防腐蚀性能,且最佳质量分数为1.0%,此时腐蚀电流分别达到0.2
随着智能网联汽车技术和产业的不断发展,智能网联汽车逐渐成为人们交通出行的选择之一.但受智能网联汽车自身环境感知系统对特定道路交通场景信息处理的局限,无法实现在所有行驶工况下安全高效的运行,其需车路协同路侧感知技术的辅助方能更安全高效的运行.海量的车路协同感知数据是城市道路和高速公路车路协同、运行分析和科学管理的宝藏,理解和分析这些数据是车路协同路侧感知融合的关键.面对车路协同路侧多传感器的不同数据,如何高效准确地挖掘和提取雷达、视频在不同时间、不同空间维度的数据,实现对重点交通场景(如视野盲区、急转弯道、
As a fascinating alternative to the energy-intensive Haber-Bosch process,the electrochemically-driven N2 reduction reaction (NRR) utilizing the N2 and H2O for the production of NH3 has received enormous attention.The development and preparation of promisi