476331 Energy-Dense Liquids from Renewable Energy

Sunday, November 13, 2016
Continental 4 & 5 (Hilton San Francisco Union Square)
Mahdi Malmali, Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN

Those in the global chemical enterprise now agree that the future of the chemical industry depends on becoming more sustainable. Such a goal includes developing energy sources that are not based on fossil fuels, and that do not release large quantities of climate-changing gases. This goal implies developing technologies that effectively collect stranded renewable energy - solar and wind - and enable long-term energy storage and long-distance energy delivery from remote areas. Solar and wind energy are continuing to get cheaper, but they are far from population centers and storage/transmission is difficult. Hence, small-scale distributed manufacturing processes that directly convert the renewable energy to transportable chemicals are important.

Research Interests:

At the University of Minnesota, I have been working on designing small scale Haber-Bosch process powered by stranded wind-generated electricity. The electricity generated by windmills is used to split water to make hydrogen, and to separate nitrogen from air by pressure swing adsorption. The hydrogen and nitrogen are then reacted to make ammonia. This ammonia is made without the use of natural gas or coal, and hence without emission of climate-changing carbon dioxide. Our analysis of this small process shows that its performance is governed by three characteristic times, those for chemical reaction, for ammonia removal by condensation, and for unreacted gas recycle. To date, our proposed process is limited by the time for ammonia removal, that is, by how long it takes the condenser to liquefy the ammonia product. While this acceleration of ammonia removal should be straightforward, we believe it will require considerable capital investment. As a result, we have been trying to simplify and intensify the Haber-Bosch process. We have not tried to improve the catalytic steps in the reactor at all, because we believe that the existing reaction, optimized by a century of intensive effort, has produced a very rapid potential reaction as good as can be hoped. We have focused instead on reducing the operating pressure and rapidly separating the ammonia produced. In my research, I have showed that the conversion could be increased from 20% to over 90% by coupling reaction and absorption. I have also showed how the operating pressure could be cut from 130 bar to 20 bar, while increasing the specific rate of reaction by cutting the product concentration in the reactor.

My future research has its origin in efforts to develop novel small-scale distributed production processes from stranded renewable energy, for production of carbon-neutral liquid fuels. In particular, I am interested in developing: devices that enable low-pressure ammonia synthesis via reactive-separation in a single vessel; processes for enhanced synthesis of renewable methanol for sustainable chemical industry; and novel supported adsorbents for facile mass and heat transfer for chemical synthesis.

Teaching Interests:

My philosophy of teaching was shaped and developed from my experience as a teaching assistant and guest lecturer in various undergraduate and graduate level courses. Whether I am teaching or learning, I am strongly committed and strive to be student-centered, engaging with students for active learning, and to support diversity as well as cooperation among everyone.

Prior Teaching Experience

My passion for academia and learning culminated into a longing to teach - a way to help others by imparting my knowledge or method of understanding. As a result, my aspirations to teach have pressed me to seek the most unique and challenging positions related to teaching. I have taught as a guest lecturer and teaching assistant in multiple undergraduate and graduate courses in the following subjects: Chemical Engineering Reactions, Mass Transfer, Senior Chemical Engineering Design, and Advanced Membrane Separations.

Teaching in academia requires continual development of one’s teaching ability. This aptitude to constantly improve has been my motivation to stay informed not only with the latest practices in chemical engineering, but also the art of teaching. In regards to chemical engineering practices, I am continually interested in exploring and pursuing different strategies for teaching chemical engineering principles. Additionally, my enthusiasm propelled me to take part in the Senior Chemical Engineering Product Design course at the University of Minnesota. In this activity, we are piloting new undergraduate product design projects using chemical engineering principles familiar to students, but have unique design objectives that are innovative for students. The outcomes of our effort was presented at the 2016 American Society of Educational Engineering in New Orleans. In addition, a manuscript based on this work is currently under preparation that will explain the lessons we as faculty members learned, practices we recommend, and objectives that we accomplished.

My fervent desire for teaching extends beyond the classroom as I incorporate teaching principles in my daily life when working with family members, friends, and to people I have never met. [Add More]

Future Teaching Plans

I am prepared to teach the following courses:

- Reaction Kinetics and Reaction Engineering

- Chemical Engineering Design

- Mass Transfer

- Separation Processes

- Junior and Senior Chemical Engineering Lab

As a well-trained chemical engineer, I am more than capable and willing to teach other courses based on the department’s needs. I am also personally interested in developing an elective course called “Novel Separation Processes for Sustainability,” that I plan to offer to graduate students and upper level undergraduate students.

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