alternativeАльтернативная энергетика и экология (ISJAEE)Alternative Energy and Ecology (ISJAEE)1608-8298Международный издательский дом научной периодики "Спейс10.15518/isjaee.2019.19-21.045-060alternative-1764Research ArticleIV. ВОДОРОДНАЯ ЭКОНОМИКА 12. Водородная экономикаIV. HYDROGEN ECONOMY. 12. Hydrogen EconomyКатализаторы CuO/ZnO для паровой конверсии метанола. Роль степени полярности и площади поверхности подложкиCuO/ZnO Catalysts for Methanol Steam Reforming: the Role of the Upport Polarity Ratio and Surface AreaМатеос-ПедрероС.Mateos-PedreroСecilia

Лаборатория LEPABE – Кафедра химической инженерии, инженерный факультет

LEPABE-Departamento de Engenharia Química, Faculdade de Engenharia

cmpedrero@fe.up.ptСильваУ.SilvaHugo

Лаборатория LEPABE – Кафедра химической инженерии, инженерный факультет

LEPABE-Departamento de Engenharia Química, Faculdade de Engenharia

Пахеко ТанакаД. А.Pacheco TanakaDavid A.

Лаборатория LEPABE – Кафедра химической инженерии, инженерный факультет

LEPABE-Departamento de Engenharia Química, Faculdade de Engenharia

ЛигуориС.LiguoryS.ИулианеллиА.IulianelliAdolfoБазилеА.BasileAngeloМендесА.MendesAdelio

Лаборатория LEPABE – Кафедра химической инженерии, инженерный факультет

LEPABE-Departamento de Engenharia Química, Faculdade de Engenharia

Университет ПортоПортугалияUniversidade do PortoPortugalНациональный научный центр Италии ITM-CNRИталияITM-CNRItaly201920092019019-214560Copyright © Международный издательский дом научной периодики "Спейс, 20192019Международный издательский дом научной периодики "СпейсМеждународный издательский дом научной периодики "Спейсhttps://www.isjaee.com/jour/about/submissions#copyrightNoticehttps://www.isjaee.com/jour/article/view/1764

В работе исследовалось влияние площади поверхности и степени полярности подложки ZnO на каталитические свойства катализатора CuO/ZnO для паровой конверсии метанола (ПКМ). Площадь ZnO поверхности варьировалась путем изменения температуры прокаливания, а степень их полярности – использованием разных предшественников Zn (ацетат или нитрат цинка). Установлено, что при увеличении площади поверхности ZnO дисперсия и площадь поверхности меди увеличивается, а степень полярности ZnO сильно влияет на восстанавливаемость медных образцов. Более высокая степень полярности способствует восстанавливаемости, что объясняется активным взаимодействием меди с «более полярной» подложкой ZnO. Интересно отметить, что селективность катализаторов CuO/ZnO (с меньшим количеством CO) повышается с ростом степени полярности носителей ZnO. Результаты проведенных экспериментов также подтвердили, что катализатор CuO/ZnOAc-375 обладает большей селективностью (до 90 %), чем аналогичный образец CuO/ZnO/Al2O3 марки G66-MR производства Süd Chemie AG. Активность наиболее эффективного катализатора (CuO/ZnOAc-375) изучалась в Pd-композитном мембранном реакторе и в традиционном реакторе с уплотненным слоем. В результате эксперимента получены значения восстановления водорода ~75 % и чистоты проникающего водорода более 90 %. Применение мембранного реактора на основе палладия позволило повысить эффективность процесса конверсии метанола за счет частичного подавления обратной реакции ПКМ, а также чистоту получаемого водорода для высокотемпературных топливных элементов с протонообменной мембраной.

The effect of surface area and polarity ratio of ZnO support on the catalytic properties of CuO/ZnO catalyst for methanol steam reforming (MSR) are studied. The surface area of ZnO was varied changing the calcination temperature, and its polarity ratio was modified using different Zn precursors, zinc acetate and zinc nitrate. It was found that the copper dispersion and copper surface area increase with the surface area of the ZnO support, and the polarity ratio of ZnO strongly influences the reducibility of copper species. A higher polarity ratio promotes the reducibility, which is attributed to a strong interaction between copper and the more polar ZnO support. Interestingly, it was observed that the selectivity of CuO/ZnO catalysts (lower CO yield) increases with the polarity ratio of ZnO carriers. As another key result, CuO/ZnOAc-375 catalyst has proven to be more selective (up to 90%) than a reference CuO/ZnO/Al2O3 sample (G66-MR, Süd Chemie). The activity of the best performing catalyst, CuO/ZnOAc-375, was assessed in a Pd-composite membrane reactor and in a conventional packed-bed reactor. A hydrogen recovery of ca. 75% and a hydrogen permeate purity of more than 90% was obtained. The Pd-based membrane reactor allowed to improve the methanol conversion, by partially suppressing the methanol steam reforming backward reaction, besides upgrading the reformate hydrogen purity for use in HT-PEMFC.

катализаторы CuO/ZnOстепень полярностипаровая конверсия метаноласелективность к COPdмембранаCuO/ZnO catalystspolarity ratiomethanol steam reformingCO selectivityPd-membraneНастоящая работа выполнена в рамках проекта «SYM – Produção de Metanol da Eletrólise da água, usando Elétrodos de Grafite (Получение метанола путем электролиза воды с использованием графитовых электродов)», (FCOMP-01-0202-FEDER-038899) при финансовой поддержке Европейского фонда регионального развития по линии Национальной стратегической рамочной программы. Авторы выражают благодарность Седьмой Рамочной Программе Европейского Союза по развитию научных исследований и технологий в области топливных ячеек и водорода (FP7/2007-2013) за финансовую помощь, оказанную при проведении ряда исследований (Договор о предоставлении гранта № [303476]). Авторы благодарны профессору Ю. Хуан (Y. Huang) из Нанкинского технологического университета, Китай, за подготовку Pd-композитной мембраны, используемой в настоящей работе. Сесилия Матеос-Педреро (Cecilia Mateos-Pedrero) признательна Португальскому Фонду науки и техники за предоставление постдокторского гранта (Договор SFRH/BPD/97114/2013). Исследования У. Сильва (Hugo Silva) выполнены при финансовой поддержке Португальского Фонда науки и техники (Договор SFRH/BD/45890/2008).The authors would like to thank the European Union’s Seventh Framework Programme (FP7/2007-2013) for the Fuel Cells and Hydrogen Joint Technology Initiative under grant agreement No [303476] due to the funding received for part of this work. This work was performed under the project “SYM – Produção deb Metanol por Electrólise de Agua, usando Electrodos de Grafite” (ref.bFCOMP-01-0202-FEDER-038899), financed by European Regional Development Fund (ERDF), through the Operational Program for Competitiveness Factors (POFC) in the National Strategic Reference Framework (NSRF), in the framework of the Incentive system for technology research and development. Dr. C. 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The authors declare that there are no conflicts of interest present.