“When molecules are straight and narrow, we use them in lipsticks and candles. But if we give the molecules arms and legs, we can use them as lubricants,” explains Santiesteban, an expert in catalyst technology at ExxonMobil Research and Engineering Co. “We have to find a catalyst that will give us the product we desire.” When the catalyst they want doesn’t exist, Santiesteban and his team work to create one from scratch. This work is challenging—and it’s the reason the Mexican-born ExxonMobil engineer was recently recognized by the National Academy of Engineering (NAE).
Catalysts: For change
Catalysts accelerate chemical reactions. An everyday example is a catalytic converter in a car, which uses chemical compounds to speed up the removal of pollution.
In refineries, catalysts help transform petroleum into other useful products, playing the same role as enzymes in our bodies. In both cases, a chemical reaction occurs that changes the way molecules are shaped.
“My job is to come up with new pathways to create chemicals that our society needs,” says Santiesteban. Producing those chemicals—which are used to make everything from fabric to soap to fuel—requires a variety of molecules. Each catalyst relies on its own set of specific molecules.
This year’s group of 102 NAE inductees includes masters of cryptography, creators of undersea optical communications and developers of novel drugs. The NAE recognized Santiesteban for “developing and commercializing catalytic systems that aid in the manufacture of petrochemicals and in the production of cleaner fuels.”
For a love of catalysis
Santiesteban was born in Hidalgo del Parral in the Mexican state of Chihuahua. He moved to the United States more than 30 years ago to complete a PhD in physical chemistry. Once he began studying catalysts and learning what they could do, he knew he had found his calling. “I fell in love with catalysis,” he laughs.
Catalysts aren’t just used to make polyester pants and makeup. They can also be engineered so they decrease the environmental footprint of the products they help make.
“More selective catalysts means less byproduct or less waste,” says Santiesteban. Molecularly engineered catalysts function like filters, and the goal is to use ones that are choosy about what molecules get through. That way, when the chemical reaction takes place, the right molecules are inside. The amount of waste is reduced because it takes less energy to do the job.
Even with the new batch of inductees, the organization remains an exclusive group. Worldwide fewer than 2,600 individuals enjoy NAE membership. However, Santiesteban is in good company at ExxonMobil. He’s the third current employee to be included, after CEO Rex Tillerson and researcher Stuart Soled. Santiesteban holds more than 80 U.S. patents, and has authored more than 20 published scientific papers. It may sound fancy, but he’s just following his passion for speeding up chemical processes with catalysts.