23 October, 2023
By David Murphy
KAUST Ph.D. student Cristina Queirós da Silva recently won a best poster prize at the 15th edition of the biannual congress of the European Federation of Catalysis Societies (EFCATS), EuropaCat 2023.
Held in Prague, the Czech Republic, from August 27 to September 1, 2023, the congress covered important challenges in catalysis and related industrial areas. For the first time, the conference was jointly organized by the catalysis societies of the Czech Republic, Hungary, Poland and Slovakia.
Queirós da Silva, a Ph.D. candidate in chemistry, was one of 10 winners of the Best Poster Award. Her submission was titled "Effect of Fe and Ce in a manganese titania catalyst for the low-temperature catalytic reduction of NOx with NH3." It focused on the design of novel and efficient alternative catalysts for the catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3).
The work’s uniqueness relies on formulating a novel manganese-based catalyst with other metals to efficiently decrease the emission of harmful pollutants from automobiles. This research is part of a group effort between her and KAUST Catalysis Center colleagues Polina Lavrik, Sarah Komaty Zaarour, Yan Wang, Sudheesh Kumar Veeranmaril, Mohamed Nejib Hedhili and the group’s principal investigator, Professor Javier Ruiz-Martinez.
The researchers have designed a catalyst that shows promising performance at low temperatures by combining manganese oxides with other metals, such as cerium, iron and titanium. The group is now working on improving the catalyst’s water and sulfur dioxide tolerance.
“In the context of heterogeneous catalysis, we want to bring new insight into the origin of the active sites in manganese-based materials. To achieve this, we will combine catalytic activity studies with advanced characterization techniques, such as microscopy and spectroscopy. This will allow for a more robust design of catalytic materials of this type, which will hopefully lead to their commercialization one day,” Queirós da Silva explained.
For over 20 years, selective catalytic reduction with ammonia (NH3-SCR) has been used in vehicles to control nitrogen oxide emissions. However, current catalysts are inefficient at low temperatures, i.e., cold starts, representing up to 60% of current emissions.1
“The general problem that the project is trying to tackle is the lack of commercial catalysts that can effectively decrease nitrogen oxide emissions at low temperatures through NH3-SCR,” Queirós da Silva noted. “Since Euro 7 standards will also regulate cold start emissions for buses and lorries, this is particularly relevant now.2”
“The more specific goal of our research is to improve the performance of manganese-based catalysts, mainly by decreasing their nitrous oxide production and their resistance to poisoning by water and sulfur dioxide, which originate from fuel combustion.”
Solo success at EuropaCat 2023
Regarding her Best Poster Award win at EuropaCat 2023, Queirós da Silva said: “It felt pretty unexpected since many people were competing for the award; therefore, it was quite a pleasant surprise. I was also pleased to highlight our cutting-edge research at KAUST in Europe.
“I didn’t work in heterogeneous catalysis before coming to KAUST, so I believe this type of recognition shows that I can adapt to any new line of research and that I am going in the right direction in my Ph.D. I want to thank my supervisor, Professor Ruiz-Martinez, for all the support, my research group for always being so helpful and, of course, KAUST, for allowing me to do this type of research.”