‘My research focuses on the nickel-catalysed dry reforming reaction between CO₂ and methane to produce syngas and specifically on the mechanisms that cause deactivation of the catalyst’, says Sofie Ferwerda, PhD student in the group of Bert Weckhuysen at Utrecht University. ‘One of the problems is the occurrence of unwanted, but thermodynamically favourable, side reactions. This leads to the formation of elemental carbon, which sticks to everything, including the catalyst particles.’

Another problem is the issue of sintering, when the nickel particles get too hot. ‘High temperatures accelerate the reaction, but when they’re too high, you lose catalyst activity. It is all about finding the optimum between activity and stability. One of the solutions could be in the size of the particles. We saw that using smaller nickel particles on the support resulted in improved activity, because it is harder for the carbon to grow on smaller particles as they have relatively less flat surface area.’

Structure performance relationship

The major question that drives Ferwerda’s research is to understand the structure performance relationship of the nickel catalyst. ‘The better we can define the properties of the catalyst, the higher the chance of coming up with leads for improvement for industrial applications.’

To gain more insight into the industrial side of things, Ferwerda spent a month at the BASF facilities in Ludwigshafen. ‘It taught me a lot about upscaling and about how different issues are important at different scales. Some aspects can be very important on the lab scale that are completely irrelevant on the industrial scale, whereas other issues, for example a slight increase in pressure, may be no issue at all in the lab, but could cause enormous problems on the real-world scale of an industrial plant.’

Incorporating industrial expertise in her research proved insightful. ‘I got a lot of input on how to design my experiments, how to make sure that we study a phenomenon in a meaningful way. To do that, it is important to know the industrial conditions. For example, in the lab we use quartz reactors, but industry uses steel, which is a serious difference. Another thing is that our feedstocks are extremely pure, which is certainly not the case in industry where they aim to use waste gas.’

Hard to navigate

But the differences are not only related to the specs, Ferwerda explains. ‘There is also a huge difference in what you aim to achieve. In academia, we want to understand a phenomenon in as much detail as we can, whereas for industry it is far more important to know how to deal with it, how to prevent or promote it. Whatever is needed to ensure the highest yield of product.’

Those different approaches sometimes make it hard to navigate between both worlds. ‘On the one hand, you want complete understanding, but your industrial partners try to push you towards providing a solution. That can be difficult, but it also gave me the feeling that what I am doing is actually relevant. I think my thesis will serve both ends, with a part on the mechanistic studies and a part on the leads for industrial improvement.’ As for her career choices, Ferwerda foresees a move to industry. ‘Probably first with a start-up or smaller company. But in any case, it has to be on CO₂ conversion or another sustainability topic. That I know for sure.’