What is a catalyst and how does catalysis work?


My name is Kim Boding Johannsen.

I'm a chemical engineer and I work in Research and Development here in Topsoe.

Today, I'm standing in our chemical lab in Lyngby, Denmark, a part of our R&D Unit.

In Topsoe, we work in the field of catalysis.

With catalysis, we help our clients run the chemical reactions in their production plants

in order to produce different chemicals we need in our society.

Without catalysis, we would not have gasoline, plastics, polyesters, artificial fertilizer,

and countless other products in the volumes we need.

So what is a catalyst and how does catalysis work?

A catalyst is a compound that accelerates chemical reactions.

This process is called "catalysis".

Catalysts are very efficient and typically make a chemical reaction one million times


Imagine this: you have two identical production plants; one is using catalysts, and the other

is not.

Production plant number one can produce one million tonnes of, for example, ammonia in

the same amount of time as production plant number two can produce only one tonne of ammonia.

That's why catalysis is indispensable for industry and society, and we could not mass-produce

most of the products we take for granted without it.

Catalysts reduce the binding energy between atoms and molecules.

This makes it easier to react these molecules to form the desired product.

Our catalysts in Topsoe come in all shapes and sizes, and we have around 150 different

types of catalysts.

Let me show you an example of one of our popular catalysts, TK.

TK catalysts are used by refineries to remove harmful sulfur and turn crude oil into gasoline

and diesel.

At the refinery, around 100 tonnes of TK catalyst is placed in a large metal pipe, called a

chemical reactor.

The purpose of the process is to convert sulfur-containing diesel into sulfur-free diesel in order to

ensure a clean exhaust gas from diesel cars.

Sulfur-containing diesel is mixed with hydrogen and passed through the catalyst where the

mixture reacts to sulfur-free diesel and hydrogen sulfide.

The hydrogen sulfide is subsequently removed and ultimately converted into fertilizer,

and we are left with a desired product, sulfur-free diesel in a continuous process.

This process layout, using a continuous flow over a solid catalyst, is the simplest and

cheapest way of running a catalytic process in an industrial plant.

In a solid catalyst, the catalytic reaction takes place on the surface of the catalyst.

In order to make the best catalysts, we need to be able to design the surface of the catalyst

down to the nanoscale.

Optimizing the nanostructure of the surface combined with maximizing the available surface

area and the microporosity of the catalyst are all essential tasks in order to design

an optimal catalyst.

Next step is to optimize the size and shape of the catalyst before we can move to production

of the catalyst in tonne-scale in our own production plants.

All these steps need to be optimized in order to deliver the best and most effective catalysts

to our customers and their mega-scale plants.