Nanoengineering X/AlOOH-Al2O3 Sols by Sequential Adsorption to Produce Xerogel Ceramic Catalytic Films for Environmental Pollution Control and Nanoparticles for BaSO4 Scale Control in Water

作者：Sermon P A^*; Worsley M; Abdulla S A E; Collins I R

来源：Journal of the Australian Ceramic Society, 2011, 47(2): 82-88.

• sol-gel
• AlOOH
• boehmite
• ceramic films
• pollution control catalysis and BaSO4 scale control

Colloidal AlOOH (90-100nm in average size but with needle-like morphology) has been prepared by sol-gel routes. Then a sequential adsorption route has been used to nanoengineer novel catalysts and BaSO4-scale control agents. First, it has been shown that oxalate ions (C2O4-) can be adsorbed onto the surface of the water-dispersed colloidal AlOOH. When La-(aq)(3+) and Co-(aq)(3+) (or Ba-(aq)(2+) and Ce-(aq)(4+)) are introduced to dispersed oxalate/AlOOH, then the cations adsorb and the M-1-M-2/oxalate/AlOOH forms. This produces fractal ceramic film coatings and after drying and calcinations LaCO3/AlOOH (or BaCeO3/AlOOH) and then highly-dispersed LaCO3/Al2O3 (or BaCeO3/Al2O3) are formed. These have useful catalytic activity in CO oxidation. We expect to show that one can fine-tune the M-1-M-2 pair and loading to give the lowest CO conversion light-off temperatures. Second, it has also been demonstrated that sulfate anions adsorb onto water-dispersed colloidal AlOOH without destabilizing this and then Ba-(aq)(2+) adsorb onto SO42-/AlOOH to give BaSO4/AlOOH. Thus the AlOOH nanoparticulate chaperones ensure BaSO4 grows safely when water rich in Ba-(aq)(2+) is introduced. This may be useful in barite scale control in oil-wells worldwide.

• 出版日期2011