Injection of nanoparticles into cooled process gas

The product gas from the 802 + 0.502 SO3 oxidation converter leaves the last catalyst bed at 390-400 °C (Fig. 26.1). It typically contains  

It is cooled to 270-290 °C and continuously sent to sulfuric acid condensation 

The first step in treating the cooled gas from SO2-I- 0.502 SO3 oxidation is injection of solid silica nanoparticles, 2-100 nm (2 x 10 to 100 x 10 m) diameter. These particles provide condensation sites for H2S04(g) produced by the following reaction  

They also serve as condensation sites for the H2S04(g) already in the converter exit gas, i.e.. 

The sulfuric acid condenses mainly on the injected particles (Christensen, 2008 Schoubye, 1982). It also condenses on the glass tube walls and to a much lesser extent, homogeneously. 

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