共查询到18条相似文献,搜索用时 53 毫秒
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我国化工企业在供给大量化工产品的同时也产生一定量的污水。这些污水成分复杂、有机物浓度偏高、高盐度、难以用生化法降解、处理难度大。常规的废水处理方法占地面积大、低效,要做到达标排放费用高昂。与其耗费大量资源处理污水达标排放,不如利用新技术将污水转化为可使用的化工产品,如氢和其它化学品。利用污水产生的氢可视为蓝氢或者绿氢,尤其是电解的动力来自于可再生能源的情况下。
经典的水电解制氢工艺有碱性膜电解、质子交换膜电解和高温氧化物电解,这些工艺都需要使用纯水作为原料。若将化工污水作为电解原料制氢,需要开发可耐受适量有机物、盐分的新电解电极催化剂和与之相匹配的膜,同时还需要攻克材料的腐蚀问题。
近日,中国科学院兰州化学物理研究所吕功煊团队利用AEM技术对化工废水电解制氢进行了研究,发展出以复合过渡金属为主要组成的复合电极作为AEM电解槽的阳极,镍基复合电极作为阴极的电极系统,通过串联N个相同活性面积的小室组成AEM电解槽系统。在单个小室工作电压为1.6-2.2 V的情况下,实现了电流密度为80-300 mA cm-2时稳定制氢,电解槽系统可连续运行100天,产氢的电效率可达到60%,在优化条件下可达到80%。该技术攻克了电解槽膜堵塞的难题,实现了化工废水的资源化利用转化为绿氢。后续拟通过优化电极材料的组成和改进AEM电解制氢系统,结构进一步降低能耗、提高产氢效率、实现氢气的高效分离和纯化。 相似文献
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面向氢能源、燃料电池和二氧化碳减排的制氢途径的选择 总被引:3,自引:1,他引:2
对氢气的多种制造途径加以探讨,也涉及到氢能的利用、燃料电池以及二氧化碳的减排。需要指出的是氢气并非能源,而只是能量的载体。 所以氢能的发展首先需要制造氢气。对于以化石燃料为基础的制氢过程,如煤的气化和天然气重整,需要开发更经济和环境友好的新过程,在这些新过程中要同时考虑二氧化碳的有效收集和利用问题。对于煤和生物质,在此提出了一种值得进一步深入研究的富一氧化碳气化制氢的概念。对于以氢为原料的质子交换膜燃料电池系统,必须严格控制制备的氢气中的一氧化碳和硫化氢;对于以烃类为原料的固体氧化物燃料电池,制备的合成气中的硫也需严格控制。然而,传统的脱硫方法并不适宜于这种用于燃料电池的极高深度的氢气和合成气的脱硫。氢能和燃料电池的发展是与控制二氧化碳排放紧密相关的。 相似文献
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氢能作为零碳排放能源是被公认的最清洁能源之一,如何有效可持续地产氢是未来人类步入氢能经济首先要解决的问题。电解水技术基于电化学分解水的原理,利用可再生电能或太阳能驱动水分解为氢气和氧气,被认为是最有前途和可持续性的产氢途径。然而,无论是光解水还是电解水,均需要高活性、高稳定性的非贵金属氢析出和氧析出催化剂以使水电解反应经济节能。本文介绍了我们研究所近三年在水电解方面的研究进展,其中着重介绍了:(ⅰ)氢析出催化剂,包括利用低温磷化过渡金属(氢)氧化物的方法制备过渡金属磷化物,同时过渡金属硫化物、硒化物以及碳化物等均被成功合成并被应用为有效的阴极析氢催化剂;(ⅱ)氧析出催化剂,主要包括金属磷化物、硫化物、氧化物/氢氧化物等;(ⅲ)双功能催化剂,主要包括过渡金属磷化物、硒化物、硫化物等。最后,总结展望了发展水电解非贵金属催化剂所面临的挑战与未来发展方向。 相似文献
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甲醇水蒸汽催化转化制氢研究进展 总被引:13,自引:0,他引:13
氢气是石油炼制和化学工业的重要原料 .传统的大规模制氢 ,大多采用天然气、轻油、煤焦为原料造气 ,再用深冷或吸收吸附法提取氢气 ,工艺复杂 ,投资大 ,能耗高 .中小规模制氢 .一般采用电解水法 ,缺点是电耗大 .近年来 ,也采用变压吸附技术 ( PSA)从石化过程产生的含氢气体中回收氢气 ,但受具体条件的限制[1 ] .与上述方法相比 ,甲醇 -水蒸汽转化制氢具有独特的优势 .与大规模制氢相比 ,该方法工艺流程短 ,设备简单 ,投资和能耗低 ;与电解水制氢相比 ,甲醇 -水蒸汽转化制氢可降低电耗 90 %以上 ,成本降低 30 %~ 50 % ,甲醇 -水蒸汽制氢成… 相似文献
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与传统化石能源制氢技术相比,利用可再生能源驱动电解水制氢技术具有绿色可持续和制氢效率高等优势,被认为是目前最具前景的制氢方式。然而, 由于电解水两极反应动力学缓慢、 催化剂稳定性较差, 限制了其大规模发展。此外, 阳极析氧反应存在较高的过电势, 从而导致当前制氢能耗与成本较高, 严重制约了其商业化应用。 为了解决上述问题与挑战,本文对当前发展较为成熟的碱性电解水技术进行了综合讨论与分析。 首先, 对电解水发展历程中的重要节点进行了总结, 便于读者了解该领域。进一步, 从电催化剂、 电极、 反应和系统的角度深入总结了提升电解水制氢性能的有效策略。作者分别介绍了近年来层状双金属氢氧化物基电解水催化剂、电解水制氢耦合氧化反应以及可再生能源驱动的电解水系统的重要研究进展; 同时对结构化催化剂在电解水应用中的构效关系进行了深入分析。最后, 对该领域存在的挑战和未来发展方向进行了展望,希望能为氢能的发展和推广提供一定的思路。 相似文献
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Li-juan Xiang Ling Dai Ke-xin Guo Zhen-hai Wen Su-qin Ci Jing-hong Li 《化学物理学报(中文版)》2020,33(3):263-284
Microbial electrolysis cells (MECs) present an attractive route for energy-saving hydrogen (H2) production along with treatment of various wastewaters, which can convert organic matter into H2 with the assistance of microbial electrocatalysis. However, the development of such renewable technologies for H2 production still faces considerable challenges regarding how to enhance the H2 production rate and to lower the energy and the system cost. In this review, we will focus on the recent research progress of MEC for H2 production. First, we present a brief introduction of MEC technology and the operating mechanism for H2 production. Then, the electrode materials including some typical electrocatalysts for hydrogen production are summarized and discussed. We also highlight how various substrates used in MEC affect the associated performance of hydrogen generation. Finally we presents several key scientific challenges and our perspectives on how to enhance the electrochemical performance. 相似文献
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固体氧化物电解池是一种先进的能量转换装置,具有高效、简单、灵活、环境友好等特点,是目前国际能源领域的研究热点. 本文对高温固体氧化物电解制氢技术的基本原理、关键材料、系统组成、发展历程及国内外研究现状等进行了总结和分析,小结了该技术发展面临的主要挑战,简述了清华大学在高温固体氧化物电解领域近期的研究进展,并对其未来应用前景进行了展望. 相似文献
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With the rapid development of human society, clean energy forms are imperative to sustain the normal operations of various mechanical and electrical facilities under a cozy environment. Hydrogen is considered among the most promising clean energy sources for the future. Recently, electrochemical water splitting has been considered as one of the most efficient approaches to harvest hydrogen energy, which generates only non-pollutant water on combustion. However, the sluggish anodic oxygen evolution reaction significantly restricts the efficiency of water splitting and requires a relatively high cell voltage to drive the electrolysis. Therefore, seeking a thermodynamically favorable anodic reaction to replace the sluggish oxygen evolution reaction by utilizing highly active bifunctional electrocatalysts for the anodic reaction and hydrogen evolution are crucial for achieving energy-efficient hydrogen production for industrial applications. Nevertheless, it is known that the oxygen evolution reaction can be replaced with other useful and thermodynamically favorable reactions to reduce the electrolysis voltage for realizing energy-efficient hydrogen production. Therefore, in this study, we present a bifunctional nickel nanoparticle-embedded carbon (Ni@C) prism-like microrod electrocatalyst synthesized via a two-step method involving the synthesis of a precursor metal-organic framework-74 and subsequent carbonization treatment for methanol oxidation and hydrogen evolution. The interfacial structure consisting of a nickel and carbon skeleton was realized via in situ carbonization. However, the dispersed nickel nanoparticles do not easily aggregate owing to the partition by the surrounding carbon as it would sufficiently expose the active Ni sites to the electrolytes, ensuring fast charge transfer between the catalyst and electrolytes by accelerating the electrochemical kinetics. In the anodic methanol oxidation, the products were detected as carbon dioxide and formate with faradaic efficiencies of 36.2% and 62.5%, respectively, at an applied potential of 1.55 V. Meanwhile, the Ni@C microrod catalyst demonstrated high activity and durability (2.7% current decay after 12 h of continuous operation) toward methanol oxidation, which demonstrates that methanol oxidation precedes oxidation under voltage forces. Notably, the bifunctional catalyst not only exhibits excellent performance toward methanol oxidation but also yields a low overpotential of 155 mV to drive 10 mA∙cm−2 toward hydrogen evolution in 1.0 mol∙L−1 KOH aqueous solution with 0.5 mol∙L−1 methanol at room temperature, which guarantees the hydrogen production efficiency. More importantly, the constructed two-electrode electrolyzer produced a current density of 10 mA∙cm−2 at a low cell voltage of 1.6 V, which decreased by 240 mV after replacing the oxygen evolution reaction with methanol oxidation. 相似文献
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甲醇催化氧化重整反应制氢的研究 总被引:14,自引:1,他引:13
研究了Cu/Zn/Al系列催化剂催化甲醇氧化重整反应制氢,得到活性,选择性及稳定性较好的催化剂Cu60Zn30Al5Ce5;并且考察了Cu60Zn30Al5Ce5为催化剂时,该反应的工艺条件如温度,物料配比等,当压力为0.1MPa,温度为240℃,CH3OH:H2O=1:0.8,CH3OH:O2=4:1时,甲醇的转化率达97.75%,在此反应条件下,反应100h后,甲醇的转化率仍在96%以上。 相似文献
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Qie Liu Shiqian Du Tianyang Liu Liyuan Gong Yujie Wu Jiaqi Lin Pupu Yang Gen Huang Miaoyu Li Yandong Wu Yangyang Zhou Prof. Yafei Li Prof. Li Tao Prof. Shuangyin Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(7):e202315157
Methanol steam reforming (MSR) provides an alternative way for efficient production and safe transportation of hydrogen but requires harsh conditions and complicated purification processes. In this work, an efficient electrochemical-assisted MSR reaction for pure H2 production at lower temperature (~140 °C) is developed by coupling the electrocatalysis reaction into the MSR in a polymer electrolyte membrane electrolysis reactor. By electrochemically assisted, the two critical steps including the methanol dehydrogenation and water-gas shift reaction are accelerated, which is attributed to decreasing the methanol dehydrogenation energy and promoting the dissociation of H2O to OH* by the applied potential. Furthermore, the reduced H2 partial pressure by the hydrogen oxidation and reduction process further promotes MSR. The combination of these advantages not only efficiently decreases the MSR temperature but also achieves the high rate of hydrogen production of 505 mmol H2 g Pt−1 h−1 with exceptionally high H2 selectivity (99 %) at 180 °C and a low voltage (0.4 V), and the productivity is about 30-fold than that of traditional MSR. This study opens up a new avenue to design novel electrolysis cells for hydrogen production. 相似文献
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在辉光放电分解乙醇制氢过程中, 高能电子在反应中起到了最为关键的作用, 非法拉第效应使得电流效率获得大幅度提升, 产物产量远远高于理论产量. 本文研究了乙醇水溶液辉光放电等离子体电解制氢的过程. 实验研究发现, 辉光放电分解乙醇水溶液的产物主要以H2和CO为主, 还有少量的C2H4、CH4、O2和C2H6. H2体积分数能达到59%以上, CO为20%左右. 通过对影响辉光放电的因素进行实验后发现: 乙醇体积分数的大小不会影响辉光放电的伏安特性参数; 电导率的提高会使‘Kellogg 区’收窄, 同时使放电尽快进入辉光放电. 此外, 乙醇体积分数越高H2体积分数越低, 产气速率在乙醇体积分数为30%和80%附近时达到极大值; 提高放电电压和电导率对辉光放电的影响规律是相类似的, 其实质都是增大了辉光放电加载在等离子鞘层两端的电压,H2体积分数基本不随二者的变化而变化, 但提高溶液的电导率更有利于减少辉光放电引起的焦耳热. 相似文献
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Decoupling Hydrogen and Oxygen Production in Acidic Water Electrolysis Using a Polytriphenylamine‐Based Battery Electrode
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Yuanyuan Ma Xiaoli Dong Prof. Yonggang Wang Prof. Yongyao Xia 《Angewandte Chemie (International ed. in English)》2018,57(11):2904-2908
Hydrogen production through water splitting is considered a promising approach for solar energy harvesting. However, the variable and intermittent nature of solar energy and the co‐production of H2 and O2 significantly reduce the flexibility of this approach, increasing the costs of its use in practical applications. Herein, using the reversible n‐type doping/de‐doping reaction of the solid‐state polytriphenylamine‐based battery electrode, we decouple the H2 and O2 production in acid water electrolysis. In this architecture, the H2 and O2 production occur at different times, which eliminates the issue of gas mixing and adapts to the variable and intermittent nature of solar energy, facilitating the conversion of solar energy to hydrogen (STH). Furthermore, for the first time, we demonstrate a membrane‐free solar water splitting through commercial photovoltaics and the decoupled acid water electrolysis, which potentially paves the way for a new approach for solar water splitting. 相似文献