Chemical engineering researchers have developed a new catalyst that significantly increases yield in styrene manufacturing, while simultaneously reducing energy use and greenhouse gas emissions. Styrene is a synthetic chemical that is used to make a variety of plastics, resins, and other materials. Industry estimates predict that manufacturers will be producing more than 33 million tons of styrene each year by 2023.
Conventional styrene production technologies have a single-pass yield of about 54%. In other words, for every 100 units of feedstock put into the process, it would yield 54 units of styrene out of each pass. Using the new catalyst, the researchers were able to achieve a single-pass yield of 91%.
The conversion process takes place at 500 to 600 °C — the same temperature range as conventional styrene manufacturing processes. Current techniques require injecting very large volumes of steam into the reactor where the conversion takes place. The new technique requires no steam. In practical terms, this drastically reduces the amount of energy needed to perform the conversion. Specifically, the conversion process that incorporates the new catalyst uses 82% less energy and reduces carbon dioxide emissions by 79%.
The new redox catalyst has a potassium ferrite surface for the catalytic phase and a mixed calcium manganese oxide core for lattice oxygen storage. In order to adopt the new catalyst, styrene manufacturers would need to adopt a different style of reactor than they are currently using but the cost savings from the new process should be significant.