TY - JOUR
T1 - Synthesis of ceramic membranes
T2 - Part I: Synthesis of non-supported and supported γ-alumina membranes without defects
AU - Uhlhorn, R.J.R.
AU - Huis in 't Veld, M.H.B.J.
AU - Keizer, K.
AU - Burggraaf, A.J.
PY - 1992
Y1 - 1992
N2 - Non-supported γ-alumina films are prepared from a boehmite colloidal suspension. After calcination at 600°C, the microstructure is characterized by a mean pore diameter of 3 nm, a porosity of 50% and a tortuosity of 5.5. The structure is formed by card packed, plate-shaped particles, giving rise to slit-shaped pores. Supported γ-alumina films, made by a slipcasting process using the same boehmite precursor, have a similar structure as the non-supported films. The slipcasting process is very sensitive to support characteristics and frequently yields defect films. Polyvinylalcohol (PVA) (molecular weight 72000 g mol-1) is added to the boehmite precursor (0.25 gg-1 film) to improve this process. This addition results in a less critical and better controllable drying and calcining procedure. The addition of PVA is necessary to slipcast defect free γ-alumina films on supports with pore diameters of 0.4 μm or smaller and on multi-layer supports. It has no significant effect on the resultant microstructure of the γ-alumina film, provided all PVA is removed by appropriate thermal treatment. The slipcasting rate is slower, resulting in thinner films of 3-5 μm at identical slipcasting times.
AB - Non-supported γ-alumina films are prepared from a boehmite colloidal suspension. After calcination at 600°C, the microstructure is characterized by a mean pore diameter of 3 nm, a porosity of 50% and a tortuosity of 5.5. The structure is formed by card packed, plate-shaped particles, giving rise to slit-shaped pores. Supported γ-alumina films, made by a slipcasting process using the same boehmite precursor, have a similar structure as the non-supported films. The slipcasting process is very sensitive to support characteristics and frequently yields defect films. Polyvinylalcohol (PVA) (molecular weight 72000 g mol-1) is added to the boehmite precursor (0.25 gg-1 film) to improve this process. This addition results in a less critical and better controllable drying and calcining procedure. The addition of PVA is necessary to slipcast defect free γ-alumina films on supports with pore diameters of 0.4 μm or smaller and on multi-layer supports. It has no significant effect on the resultant microstructure of the γ-alumina film, provided all PVA is removed by appropriate thermal treatment. The slipcasting rate is slower, resulting in thinner films of 3-5 μm at identical slipcasting times.
UR - http://www.scopus.com/inward/record.url?scp=34249841605&partnerID=8YFLogxK
U2 - 10.1007/BF00543947
DO - 10.1007/BF00543947
M3 - Article
AN - SCOPUS:34249841605
SN - 0022-2461
VL - 27
SP - 527
EP - 537
JO - Journal of materials science
JF - Journal of materials science
IS - 2
ER -