Microstructure control of ceramic membrane support from corundum-rutile powder mixture

The reaction sintering of porous alumina ceramic membrane support was realized at 1300 °C using commercial titanium white powder (rutile) as sintering aids. The microstructures of sintered body were significantly affected by the amount of rutile, organic pore-forming agents and sintering techniques. The results indicated that the porosity dramatically decreased and the pore radius decreased from 1.6 μm to 0.8 μm with less than 10.0 wt.% rutile addition. Correspondingly, their permeations to nitrogen depending on the pore structure parameters of the support were in the range of 11.8–26.1 km3 m− 2 h− 1 bar− 1 at 1400 °C. Organic additives up to 25.0 wt.% is appropriate, otherwise the excessive organic additives would lead to poor sintering of green support. Sintering experiments showed that the microcracks formed once the sintering temperature was over 1600 °C. To prepare porous alumina support with > 40% open porosity and 50 MPa mechanical strength along with better resistance to alkaline corrosion, the optimum sintering conditions are the sintering temperature of 1400 °C and 2–4 h holding time at this temperature.