A Study On Electrochemistry To Prepare Inorganic Membranes With Waste Aluminum

Inorganic membrane has been the center of research in recent years according to its high temperature resistance and perfect chemical stability, it will be widely utilized in environmental engineering. How to reduce the cost of inorganic membrane has become the obstacle to its development with reforming and creating kinds of synthesis technology.Nowadays many cans are dumped, the level of recycling is low, which not only pollutes the environment, but wastes the useful recycling resource. So it is meaning for conservation of environment and resource to find high level recycling method.The research successfully prepared AAO with properties of separation with electrochemistry using waste non-pure aluminum. It combines resource of waste and preparation of membrane. The purpose is to look for a new way to reduce the cost of preparation of membrane and makes a high class use of waste aluminum.The thesis has already prepared anodic aluminum oxidation (AAO) on the basis of the high pure aluminum with acid electrolyte. In the research of voltage, category of electrolyte, current and concentration of electrolyte, the process of anodic oxidation consists of barrier layer, development of microporosity and stable growth of porosity. Compared with the case in sulfuric acid and oxalic acid electrolyte, the quantum of the membrane in sulfuric acid is larger than that in oxalic acid. But the exothermic in sulfuric is larger than that in oxalic acid, oxalic acid is a better electrolyte in laboratory. The aperture and porosity are compared which in sulfuric acid and oxalic acid by SEM.The thickness of AAO is growing with the time increasing, concentration of oxalic acid increasing, current density and voltage increasing. AAO is transforming noncrystal to crystal after annealing in 850°C,1000°C,1160°C. The range of utilization is increasing from the pH 5-10 to 2-13.The thesis has prepared the AAO membrane of waste non-pure aluminum, with 0.3M oxalic acid ,40V ,20°C and 2h. The surface of AAO has some crystals through SEM, it indicates that the alloy in waste aluminum also joins the process of the anodic oxidation. The research of flow rate indicates that the flow rate increases with the voltage increasing and has no relation to concentration of electrolyte. But its flowrate is a little lower than the flow rate of AAO of high pure aluminum. The research indicates that it is feasible to prepare alumina liquid or gas membrane with old non-pure aluminum using anodic oxidation. It is hopeful to a green technology of making high level use of waste aluminum.