The purpose of this paper is to explore a membrane material with stable operation and development potential. We have understood that the stability of the organic membrane has some problems in the high temperature seawater from the previous research. Based on the previous research results, this paper focuses on the highly stable non-oxide ceramic membrane. The preparation, surface modification and distillation properties of the ceramic membrane were studied in this paper. It is divided into the following parts.

The first chapter introduces the current situation of water resources, the urgency of freshwater demand, the industrialization of seawater desalination technology and the defects of seawater desalination technology at present. The working principle of membrane distillation technology and the obstacles hindering the industrialization of membrane distillation technology, as well as the preparation and modification of ceramic membrane are all introduced. At last, the whole research thought is expounded.

The second chapter briefly introduces the raw materials and instruments used in the experiment.

The third chapter introduces two parts: One is the shaping and  sintering of β-Sialon ceramic fiber tube. The fiber tube membrane was successfully obtained by using the method of phase inversion extrusion molding combined with sintering. The stable homogeneous slurry was obtained by the type of dispersing agents, content and composition ratio of the slurry, and the properties of the ceramic membrane were characterized and optimized by adjusting the sintering temperature and other conditions. The other one is the preparation and characterization of silicon nitride and β-Sialon ceramic plate films. The silicon nitride flat film was prepared by phase inversion casting and sintering. By optimizing the size of ceramic membrane and sintering temperature, the high strength and high porosity of silicon nitride and β-sialon ceramic plate films were successfully obtained.

In chapter 5, the flux of the membrane distillation is improved on the basis of the stable and practical ceramic membrane. By improving the forming process of ceramic membrane, using the double layer curtain coating and hot pressing process of graphite sacrificial layer, the material transport flux of ceramic membrane was improved, and the water flux in the membrane distillation process was increased by more than 50 %. The efficiency of the membrane distillation process was improved, and its industrial application was further improved.

The fourth chapter introduces the surface modification of ceramic membrane, and tests the membrane distillation process of the modified ceramic membrane. The natural hydrophilicity of ceramic membrane does not apply to the process of membrane distillation. Its surface modification process is a key step to improve its service life. It has three modification methods: ( 1 ) grafting fluorine molecules on the surface; ( 2 ) the pyrolysis of inorganic nanoparticles modified by ammonia of surface of; ( 3 ) pyrolysis modification of surface poly. The three modification methods have successfully achieved the target of surface modification, and all of them have the separation effect in the membrane distillation process and obtain pure water. However, the long-term stability is different, and the graft stability of fluorine organic molecules is obviously inferior to the pyrolysis modification.

In chapter 6, the application of silicon nitride ceramic as a supporting material was introduced. The dense ZIF-8 gas separation membrane was successfully synthesized on the outer surface of the silicon nitride hollow fiber tube, and its application in carbon dioxide adsorption and separation was proved. The separation factor of hydrogen and carbon dioxide is 11.67.

The seventh chapter summarizes the work of this paper, and points out the shortcomings and development prospects of the work.