Open season on sulphur

The sulphur emitted during the combustion of fuels in vehicle engines forms sulphur oxides, which contribute to acid rain, and it also participates to increased greenhouse gas emissions. The SAMBA beamline allows the “hunt for sulphur”, a chemical reaction involving hydrogen and a metallic catalyst, to be monitored live. By controlling this type of reaction, the longer term goal is to completely remove all undesirable sulphur from diesel fuel and petrol.

Open season on sulphur

Audio Transcription

VOICE-OVER
The chemist is putting catalyst powder into an analysis cell. Catalysts are commonly used in refineries to eliminate sulphur from crude oil in order to obtain cleaner fuels. 

Virginie Moizan - Research fellow (IFP Énergies Nouvelles) 
The sulphur emitted during the combustion of fuels in vehicle engines forms sulphur oxides which contribute to acid rain, so it is logical that reducing the sulphur content of fuels will also reduce the phenomenon of acid rain. 
Sulphur also contributes to increasing greenhouse gas emissions. 

VOICE-OVER
The process of removing sulphur from oil at the refinery would not work without a catalyst. Hydrogen is also required for the success of the process. The catalyst helps hydrogen capture the sulphur during the elimination process. 

Virginie 
The catalyst accelerates the process and ensures that the hydrogen actually removes the sulphur from the oil, and not something else. 

Amélie Rochet - Chemist and PhD student (SOLEIL synchrotron-IFPEN) 
Gas settles in the pores of the catalyst. The reaction that takes place on the surface of the catalyst helps us obtain cleaner molecules. 

VOICE-OVER
However, all catalysts do not react in the same way and are not all equally efficient. Thanks to the X-rays of SOLEIL synchrotron’s SAMBA beamline, the two young researchers will be able to study the behaviour of various metal-based catalysts in detail. 
The cell is filled with metal catalyst powder – a blend of nickel and molybdenum in this case –, and is placed on the X-ray beamline. Sulphur and hydrogen are then injected into the cell. The hunt for sulphur can begin and the entire process can be monitored live on the control screens. 

Amélie 
The X-rays will detect what is going on with the molybdenum and then, just one minute later, what is happening with the nickel. This shows us how the nickel and molybdenum respond almost simultaneously (just one minute apart) and under the same conditions.

Virginie 
This is the only beamline in the world that allows us to observe both elements at exactly the same time. 
We have a film of the structural changes during the reaction and during activation throughout the catalyst’s lifecycle. 

VOICE-OVER
Thousands of measurements will be recorded. By changing certain parameters, such as temperature or pressure, the researchers hope to understand why some catalysts are more efficient than others. The longer term goal is to completely remove all undesirable sulphur from diesel fuel and petrol.