Golden Chemical Engineering Days

Chemical engineering as a discipline is in a unique position. The field is sufficiently large and diverse enough to reach across and have a significant impact on a broad range of technologies, yet small enough for its practitioners to maintain the sense of a close-knit community. How long this delicate dichotomy will hold is hard to say. But the collegiality of chemical engineers was evident during the recent annual meeting of the American Institute of Chemical Engineers (AIChE) held on Nov. 12-17 in San Francisco.

"This conference is like no other," commented John C. Chen, AIChE president and a chemical engineering professor at Lehigh University, Bethlehem, Pa. "We have more than 4,500 chemical engineers from academia, industry, and the public sector all together to discuss the cutting-edge and important aspects of chemical engineering."

"The AIChE meeting always provides a unique insight into the important challenges that chemical engineering researchers are facing," noted Martin A. Abraham, a chemical engineering professor and dean of the graduate school at the University of Toledo, in Ohio. "It provides a single venue where chemical engineers can come to take the pulse of our community."

"It is a great meeting," added Joan F. Brennecke, a chemical engineering professor at the University of Notre Dame, in Indiana. In addition to hearing "many good talks," Brennecke noted that she had "great technical conversations" in the hallways of the San Francisco Hilton, where the meeting was held. These side conversations and networking are "always an important part of AIChE," she said. "Unlike chemists, most chemical engineers, even in vastly different fields, all know each other. The AIChE meeting is the place we go to catch up."

The theme of this year's meeting, one of the largest in recent memory, was the globalization and diversity of industries served by chemical engineers, with a focus on energy and sustainability (see page 56). AIChE wants to be involved as the U.S. and the world move to new energy resources, Chen said.

One of the first events was a roundtable discussion conducted by an international group that included chemical engineers from the energy, biotechnology, and semiconductor sectors. They focused on the future of the profession of chemical engineering as the issue of sustainability has turned head-on into the chemical enterprise.

The speakers affirmed that science and engineering are crucial to addressing poverty, climate change, health care needs, and environmental degradation. As one panelist commented, synthesis of clean fuels from biomass could be considered the "new alchemy" for its contribution to sustainability.

"Biomass was a hot topic for chemical engineers in the late 1970s as we responded to the first oil crisis in 1973," chemical engineering professor Mark T. Holtzapple of Texas A&M University told C&EN. "By the early 1980s, the price of oil dropped, so interest waned. Now that we have seen $3-per-gal gasoline and there is concern that global oil production will soon peak, we are seeing a much-renewed interest."

That interest is not just by the researchers and businesses involved, he added. The number of spectators attending talks related to biofuels has increased substantially in the past few years, he said. In many of the sessions on energy and sustainability, there was standing room only, and in some cases people were spilling into the hallways.

Holtzapple's research involves converting the cellulosic material of various types of biomass or waste organic matter into carboxylate salts, which can then be used as a platform to make fuels or feedstock chemicals. His process, dubbed MixAlco, is potentially more efficient than converting biomass to ethanol, and it's being tested in a pilot plant on the Texas A&M campus.

He described his work, as well as the advantages and disadvantages of different strategies for using biomass as a raw material, during a plenary session on sustainable biorefineries. The session featured talks by scientists from academia, government, and industry, including the National Renewable Energy Laboratory, DuPont, and ConocoPhillips.

Beyond energy and sustainability, the AIChE meeting included sessions on subjects as diverse as bioseparations, catalysis and reaction engineering, fluid mechanics, microreactors, nuclear engineering, pilot-plant design, systems biology, and water resource conservation. Also featured was a joint U.S.-Japan conference on medical engineering, as well as a set of keynote lectures and award lectures and presentations.

AIChE additionally teamed up with the American Vacuum Society, which was holding its annual conference at the same time just down the street, for a joint symposium on plasma science and technology. Each society hosted sessions on the use of plasmas to probe the physics and chemistry of surfaces to characterize materials and the use of plasmas to fabricate integrated circuits, electromechanical systems, and optoelectronic devices.

The annual meeting included a concurrent National Student Conference, which this year was attended by more than 1,000 chemical engineering students. This "conference within a conference" featured an undergraduate poster competition with prizes awarded in different disciplines; a student paper competition and a student design competition; career-planning workshops, graduate school fair, and job fair; social events; and the immensely popular Chem-E-Car competition.

A team of chemical engineering students from the University of Puerto Rico, Mayagüez, took top honors in the Chem-E-Car competition, which was held as a public event sponsored by food company General Mills. The team's entry, a school bus design nicknamed "Coki," after a frog native to Puerto Rico, was powered by a hydrogen fuel cell. It outperformed the entries of 30 other university teams as some 600 spectators cheered.

The Chem-E-Car competition is a fun and practical way for students to engage in a team-oriented hands-on design project and apply their knowledge of chemical engineering principles in figuring out new ways to power a shoe-box-sized model vehicle. The teams first display their entries and present posters to explain the chemical reaction used to power their vehicles, as well as environmental and safety features of the designs. But the highlight of the competition is watching the cars in action.

The competition always heats up one hour before this demonstration phase, when students and their faculty advisers are provided the final details of exactly how far their vehicles, carrying a specified amount of water, must travel before stopping. In this year's event, the students were challenged to transport 10 mL of water 75 feet.

The teams then fly into action to make careful calculations and adjustments to their designs so that their vehicles would meet those objectives. The teams have two chances to drive their vehicle as close as possible to a finish line, with the best attempt counting. The cars can't be controlled remotely or be given any mechanical or physical assistance to start or stop.

The winners from Puerto Rico, wearing matching team racing shirts at the AIChE meeting, celebrated with their prize of $2,000, a trophy, and bragging rights. Finishing second place and receiving a $1,000 prize and trophy was a team from the University of Dayton, in Ohio. In third place was a team from the University of Maine, Orono, which received $500 and a trophy.

"The Chem-E-Car competition is always a highlight of the AIChE annual meeting for me," Chen noted. "With each year's competition, there is more creativity from our student members," he said.

An important reason that many faculty attend the AIChE meeting is, in fact, to check out some of the students as prospective new faculty members, Notre Dame's Brennecke noted. "Chemical engineering departments still see themselves as a single unit, as opposed to large chemistry departments where the focus is on recruiting candidates in your discipline, such as physical, organic, or inorganic chemistry," she explained. "We all want to see all the candidates."

There are two ways to accomplish this at the AIChE meeting, she said. One is to attend a special forum, held on the first day of the meeting, to meet faculty candidates. The second way is to do a lot of "session hopping" to listen to talks given by the candidates.

The AIChE meeting is thus a great venue for graduate students to give talks and to get broad exposure and experience for advancing their careers, Brennecke added. For example, Berlyn R. Mellein in Brennecke's group gave a talk on her research in the use of CO₂ as a cosolvent to separate organic liquids from ionic liquids.

Ionic liquids are organic salts that are nonvolatile liquids at room temperature, and they are proving to be useful as alternative separation and reaction solvents. Their properties are tunable by selecting different organic cations and inorganic ions.

During the meeting, Brennecke received the 2006 AIChE Professional Progress Award, one of the institute's highest honors, for her seminal work on ionic liquids. In one of the technical sessions, she gave a talk on using ionic liquids to capture CO₂, SO₂, and other environmentally problematic industrial flue gases. This work includes ionic liquids with CO₂ absorption capacities as high as that of conventional alkanolamine-based scrubber technology, she said. But the ionic liquids have a lower enthalpy of absorption, which means "lower energy cost for regenerating the absorbent material," she noted.

Toledo's Abraham agreed that a major reason for attending the meeting is for the benefit of the students. Presenting their research and attending the different technical sessions "give them a much broader perspective," he said.

Several of Abraham's students gave talks related to their efforts to produce hydrogen to power fuel cells. One of the group's approaches is to convert currently available liquid fuels, such as diesel, gasoline, or jet fuel, into H₂ and CO₂ by using steam reforming, a high-temperature catalytic reaction. "While this doesn't get us away from the use of hydrocarbon resources, it does provide an opportunity to use these fuels more efficiently," Abraham said.

The challenge is the presence of sulfur in fuels, which poisons the reforming catalyst and subsequently poisons the anode catalyst of the fuel cell, Abraham told C&EN. The researchers are developing new sulfur-tolerant catalysts that can be used to make hydrogen for extended periods. The Toledo researchers also are evaluating a potential alternative technology that involves biological conversion of raw biomass into an aqueous organic broth containing ethanol, for example, followed by aqueous reforming of the organic phase to produce H₂.

Chemical engineering, like chemistry, is a field whose leaders are concerned about where the next generation of researchers will come from. Perhaps more important, chemical engineers are also concerned about where newly minted chemical engineers can go once they earn their degrees.

In a symposium on undergraduate education, speakers from industry, government, and academia took a crack at answering the fundamental question: What is a bachelor's degree in chemical engineering? The speakers agreed that an undergraduate degree in chemical engineering is one of the most versatile degrees one can have, as it lends itself to many future career paths. But they still explored some of the current trends in undergraduate research to see what types of curriculum reform might be needed.

Chemical engineering assistant professor Jamil T. Naser at Tuskegee University, in Alabama, noted that undergraduates continue to take the traditional core chemical engineering courses. These include material and energy balance, process control, heat transfer, fluid mechanics, and more. Though this fundamental education is still needed, it's not enough to equip new graduates with all the tools necessary in today's job market, Naser said.

Chemical engineering departments in universities are responding to recent changing times by changing their names, he pointed out, in part to attract students and funding. Once upon a time, all chemical engineering departments were called "chemical engineering," he said. But these days, only about 60% of the 151 AIChE-accredited departments are labeled chemical engineering. The remainder are called "chemical and ___ engineering." The most popular names filling in the blank are biological, biomedical, biomolecular, environmental, and materials. Naser quipped that the AIChE acronym perhaps should stand for the American Institute of Changing Engineers.

"Change isn't something bad," he said. "It can be good if you are changing in the right direction." He suggested that "tuning" the chemical engineering curriculum to give students options to learn about new high-demand subfields is natural. This could come in the form of offering a minor in a specialty area. At Tuskegee, these include biochemical and environmental engineering, in addition to a premed option. The department has also added emphasis on written and oral communication and on ethics. "As little as one course in a target area can make a difference," Naser said.

Another highlight of the annual AIChE meeting is a set of keynote lectures, which in San Francisco were attended by more than 500 people. One of the most popular talks was the 58th annual AIChE Institute Lecture, which was delivered by Carol K. Hall, a professor of chemical and biomolecular engineering at North Carolina State University.

Hall is credited with modernizing chemical engineering thermodynamics research. She kept the audience's attention with a description of her work on applied thermodynamics and molecular simulations to study the formation of protein aggregates. The goal of the research is to better understand the 24 known amyloid protein neurodegenerative diseases, which include Alzheimer's disease, Parkinson's disease, Huntington's disease, and prion diseases, she said.

Her group is refining a computer simulation using polyalanine as a model to follow the kinetics of the unfolding of proteins from their native, lowest free-energy state to form random coils. These coils in turn latch onto one another to slowly form amorphous aggregates that converge to form larger β-sheet structures. These structures finally form larger fibrils known as plaques, Hall explained. The modeling allows researchers to visualize the temperature-dependent gyrations of the protein strands to form the fibrils, which some people think are the cause of amyloid diseases, she said.

Hall included personal notes that her father suffered from Pick's disease, a degenerative brain disease similar to Alzheimer's disease, and that her mother had Alzheimer's. Hall called for more funding, noting that the amount of funding directed toward Alzheimer's research, about $650 million per year, is small, given the millions of people affected by the disease. She joked that more money is spent on breast implants and sexual dysfunction.

One of the well-attended topical conferences in San Francisco focused on product design. It included some 60 papers and addressed the latest developments in estimation and modeling of product properties, management and business issues, sustainability, and incorporating product design into chemical engineering education. The conference kicked off with a plenary session featuring several invited speakers and a panel discussion.

Robert S. Langer of Massachusetts Institute of Technology gave a lively overview of his approach to creating and implementing medical technologies. Langer is known for being a prolific inventor and revolutionizing drug delivery and the engineering of human tissue. He has more than 550 patents for drug delivery devices and medical implants that have been licensed to more than 180 pharmaceutical, biotechnology, and chemical companies, many of which he has helped start. His mile-a-minute talk in San Francisco gave the audience a personal view of how he thinks on his feet, comes up with so many ideas, and finds clever ways to move them from paper to the lab and into companies.

"The success or failure of a company depends not only on the scientific issues, but also the nonscientific issues such as the quality of the business staff," he noted. The secret is naturally knowing what to look for in a product, such as market need, regulatory hurdles, and competition and patent protection, he said. A critical next step is establishing a platform technology, such as a single manufacturing process that can be expanded and used over and over again for different products, rather than having to use a new process for each new product.

Langer proceeded to describe the ups and downs associated with several of his top inventions. One example he gave was porous polymeric microspheres that slowly release drugs. In the late 1970s, Langer figured out the right combination of biocompatible copolymers necessary to allow controlled release of small molecules or larger molecules such as peptides and proteins. This was an accomplishment that most scientists at the time didn't think was possible, he said, and it took several years to convince the patent examiner that the idea was novel and worked.

Today, the microspheres, or particles like them, serve as a platform technology for 10 injectable products approved or in clinical trials to treat schizophrenia, alcoholism, growth-hormone deficiency, diabetes, and other health problems, he noted. The technology was licensed and is being commercialized by Alkermes, a Cambridge, Mass.-based company that now has 750 employees, along with other companies. "It all got started with that one discovery," he said.

In another example, Langer described his development of shape-memory polymers. He related that he was riding an exercise bike and looking at Life magazine, in which he read a story about shape-memory metals that could be reshaped by heating—for example, to repair a car after an accident.

One thought led to another, he said, and he wondered if one could create stringlike biocompatible polymers that could be inserted into the body during minimally invasive endoscopic surgery and do something useful, such as form a coil to serve as a stent or serve as a smart suture that can tie itself into a perfect knot. His group was soon able to make such polymers that have one shape at room temperature but take on a different shape at body temperature. Just recently, his lab helped develop shape-memory polymers that can take on three different shapes (C&EN, Nov. 27, page 25). The polymers are being commercially developed by mNemoscience, based in Aachen, Germany.

"It helps to get started with a seminal paper in a top journal or a seminal patent that is sufficiently broad in scope to block others from obtaining a similar patent," Langer advised. "It's also very useful to demonstrate early on that a technology works in vivo. These accomplishments draw interest and generate excitement among the companies and investors."

So it went at the AIChE meeting this year. Chemical engineers celebrated their discipline the week before Thanksgiving by sharing their research and enjoying good fellowship—and of course also enjoying sourdough bread, ethnic foods, and the rattle of cable cars through the hills of San Francisco.