XAS Applications in Chemical Engineering

 

Polymerization of SiO2 units: From Quartz to Silica

Many topics in Chemical Engineering ask for structural information. Examples how such information can be achieved are shown here: In Quartz SiO2 units are linked together in highly ordered patterns whereas this is not the case for simple silicates. The polymerization of SiO2 units can be resolved at Si K-edge.Polimerization in Silicates: Si K-edge XANES shows an edge shift with increasing chain length.

photo: Figure 1: The polymerization of SiO2 units can be resolved at Si K-edge

Figure 1: The polymerization of SiO2 units can be resolved at Si K-edge

photo: Figure 2: Overview of Silicate polymers(from website)

Figure 2: Overview of Silicate polymers(from website)

Vulcanization of Rubber: Thermo-oxidative ageing – at S K-edge

Fig. 3 shows the processes at the sulfur crosslinks of vulcanized rubber during thermo-oxidative aging at sulfur K-edge using X-ray absorption near-edge structure (XANES).

Figure 3: Vulcanization of Rubber: Thermo-oxidative aging - at S K-edge.

Figure 3: Vulcanization of Rubber: Thermo-oxidative aging - at S K-edge.