Preparation Of Asymmetric Ceramic Filter Membranes

The aim of this research is to prepare asymmetric ceramic filter membranes. Studied on the manufacture method of prepare alumina ceramic filter membranes by solid-state-particles and the characterization of alumina ceramic filter membranes. membranes with smooth surface and adjustable porosity and Pore size distribution were obtained.Researched the effect of the particle size and particle size distribution of aggregate on pore structure, the research shows use aggregate with narrow particle size distribution make the Pore size distribution of the ceramic membranes more narrower, the porosities more higher. The pore size is relevant to the particle size of aggregate, in this research D/d≈3.5.Researched the effect of the amount and particle size of vitrified bonding agent on mechanical property of ceramic membranes. With the increase of the content of vitrified bonding agent, the strength of the ceramic membranes enhanced, the porosity of the ceramic membranes decreased, the best content of vitrified bonding agent is 18%. The particle size can inflect the roasting temperature, pore size and pore size distribution of the ceramic membranes. The particle size of aggregate should be 3～4 times bigger than vitrified bonding agent.research on the theory and technique on stabilization of slurry. The experimentation indicates it has the greatest effect when we put 1.2wt% dispersing agent in the slurry and make the pH between 9～10.Researched the effect of the amount and particle size of pore-forming agent on mechanical property of ceramic membranes. With the increase of the content of pore-forming agent, the strength of the ceramic membranes fell, the porosity of the ceramic membranes increased, the best content of pore-forming agent is between 14wt%～26wt%. The narrower the particle size distribution of pore-forming agent ,the narrower the pore size distribution of ceramic membranes.The pore structure, retention and chemical stability were characterized. The SEM photo shows the ceramic membranes has network pore structure, the thickness of the ceramic membrane is between 300～400nm. Test shows the porosity of the membrane is 47.2%, The average Pore size of the membrane is2.39μm. The ceramic membranes has great retention to micro powder at the particle size between 1.2～7μm. acid fastness of ceramic membranes is much better then resistance to alkali.According to the experiment results, asymmetric ceramic filter membranes made in this research have narrower aperture size distribution, bigger flux for water, higher strength. The experiment results can be used in industrial production. It will hasten the development of separate technology.