Dynamic light scattering and angular dissymmetry for the in situ measurement of silicon dioxide particle synthesis in flames.

Particle size measurements have been made of silica formation in a counterflow diffusion flame reactor utilizing dynamic light scattering and angular dissymmetry methods. The results suggest that the techniques compare quite favorably in conditions of high signal to noise. However, the dynamic light scattering technique degrades rapidly as the signal strength declines, resulting in erroneously small particle diameters. As a general rule dynamic light scattering does not seem to possess the versatility and robustness of the classical techniques as a possible on-line diagnostic for process control. The drawbacks and limitations of the two techniques are also discussed.