The Importance of Green Chemistry

Focus on renewable energy leans toward types and delivery systems; solar, wind, geothermal, fuel cells, photovoltaics and turbines, for example.

But the concept of renewables can extend to the materials that make these delivery systems. That is where green chemistry comes into play.

The EPA defines green chemistry this way:

Green chemistry, also known as sustainable chemistry, is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry applies across the life cycle, including the design, manufacture, and use of a chemical product.

As Dr. Richard Wool, a professor of chemical engineering who founded and runs the Affordable Composites from Renewable Sources, or ACRES lab, at the University of Delaware, explains, renewable energy systems can be energy and resource intensive to create. To the degree that we can find suitable renewable materials to create them, we must or we are going to run into problems with toxic processes that limited resources when it comes to renewables.

That is where Dr. Wool’s lab focuses; finding cheap, plentiful, renewable materials to make polymers and composites that replace petroleum and mineral based components. Whether it is chicken feathers to power the hydrogen economy or soybeans to create hurricane resistant - and highly insulating - roofs, green chemistry looks to solve some of the green economies largest problems. In fact, Dr. Wool believes that solutions to global warming can be found in green chemistry.

Dr. Wool is particularly excited about opportunities in wind and solar and how green chemistry can make them even better. “Just one hour of sunlight striking the earth’s surface can provide enough energy to meet the needs of the whole planet for an entire year,” says Dr. Wool. Capturing that energy is the challenge, and one that green chemistry may help to solve. “We can convert the solar energy to hydrogen in order to store it, but the issue becomes the materials needed to create the storage. We have found that carbonized chicken feathers work.” They are still early in their research, but Dr. Wool sees this as a strong beginning using an agricultural by-product that goes to waste. And he believes that solving the hydrogen storage problem is the most important one for green chemistry to solve.

Dr. Wool has an unusual view when it comes to bioplastics; he doesn’t believe they should biodegrade. “There is a major paradigm shift in the concept of what a green plastic material should be,” he explained to me. “The old idea was that it should be biodegradable and derived from renewable resources. This was the perceived solution to Landfill problems of the 1980's. The current new idea is that the plastic should help reduce global warming and be derived from renewable biomass by removing CO2 from the atmosphere through photo-synthesis, be synthesized to plastic at low energy consumption and not give back the CO2 to the atmosphere through biodegradation.” He cites as an example polyethylene made from ethylene gas derived from sugar cane ethanol,

Some of the projects coming out of Dr. Wool’s lab are finding commercial use. Cara Plastics, in collaboration with manufacturing partner DynaChem, for example, is marketing the bio-resins developed at ACRES to replace petroleum-based thermosetting resins. This is right in line with Dr. Wool’s premise that we can replace petroleum in many of the products and processes we use.

The next level of green chemistry is to fully support the renewable energy industry and solve its problems of materials, storage and efficiency. Dr. Wool, along with colleagues at institutions like Yale University, Howard University and Boston University, University of Manitoba, Nottingham University, Bogazici University and others have proposed a multi-disciplinary Green Engineered Materials (GEM) society and center. GEM will focus on the development of bio-based materials in support of renewable energies like solar wind and hydro, and related advanced materials technologies, especially for use in energy-efficient housing.

It’s green chemistry solving global warming in action.