Fabrication Of Porous Alumina Ceramic With Special Wettability And Their Applications In Oil/water Seperation

The research on separation of water and oil has important significance on the reclamation of water resource and environmental protection.Interfacial material with special wettability can separate water from oil in oil-water mixtures due to dramatic difference in wettability of water and oil.The aim of thesis was to fabricate two types of porous Al2O3 ceramic materials with different wettability,and to design an oil-water separation device in order to investigate the oil-water separationperformance.The main research contents and results are as following:1.In this work,A series of porous alumina ceramics were prepared by sintering alumina powder aggregates formed with the mass fraction of 20%colloidal silica as bonding agent at various temperature.Alumina powders with 0.5-1.5 ?m,20-30 ?m,40-60 ?m,80-100 ?m,120-150 ?m,200-240 ?m were used in preparation of these porous ceramics.The obtained porous alumina ceramics have good mechanical strength and chemical stability.2.The superhydrophobic and superoleophilic porous alumina ceramic with particle diameters of 0.5-1.5?m was successful obtained by modifying with octadecyltrichlorosilane(with low surface free energy),which with a water contact angle of 155.1°and a oil contact angle of 0°.The prepared materials can separate the oil slick which is heavier than water.Meanwhile,The prepared materials possess high efficiency of oil/water seperation and good recycle efficiency.3.The superhydrophilic and underwater superoleophobic self-cleaning porous alumina ceramic with particle diameters of 120-150 ?m was prepared by coating TiO2 film on the surface of porous alumina ceramic.Such a porous ceramic exhibited 0° contact angle for both the water and oil in the air,and 152.2°contact angle for oil in the water.The results showed that efficiency of oil/water separation and recycle efficiency of superhydrophilic and underwater superoleophobic porous alumina ceramic are excellent and it can separate the oil slick which is lighter than water.Furthermore,The superhydrophilic and underwater superoleophobic self-cleaning porous alumina ceramic possess excellent photocatalysis to achieve self-cleaning and regeneration.