Hydrofluoric acid corrosion behaviour of SiO₂ glass used to prepare glass hollow fibre membrane

Abstract

This paper describes the corrosion behaviour of SiO₂ glass hollow fibres by hydrofluoric acid (HF). The decrease of corrosion rate after 6 h etching could be explained by the change of surface area and concentration of the HF solution. The small and positive ΔS implies that the decrease in disordering takes place due to the transformation of the amorphous glass phase to SiF₄ and Na₂SiF₆. The results show that many pit typed corrosion masks showed on the surface of the glass hollow fibres. The microflaws and defects lead to the formation of pits on the glass surface.

Keywords:

• Hydrofluoric acid
• Glass
• Acid corrosion
• Scanning electron microscopy

The authors thank the financial support of the National Basic Research Development Program of China (973 Program, 2012CB722706), the National Natural Science Foundation of China (20874073) and the University Science and Technology Development Plans of Tianjin (20110307).