Preparation And Properties Of Copper Hydroxide/Copper Oxide Nanowire Homogeneous Membrance

Membrane separation is an emerging discipline that uses separation membranes as the core to selectively separate mixed solutions of different particle sizes.Membrane separation technology has the functions of separation,concentration,purification and refining.It has the advantages of high separation efficiency,low energy consumption,no pollution,simple operation process and easy control.Therefore,membrane separation technology has been widely used in water treatment,medicine,chemical,biological,metallurgical,environmental protection,energy,food and other fields.The development of nanotechnology has injected new vitality into the research and development of new membrane technology.In this paper,ultra-long Cu(OH)2/CuO nanowires were synthesized by direct precipitation method.The Cu(OH)2/CuO ultrafiltration membranes were prepared for the first time by vacuum suction filtration and the membranes formation mechanism was studied.By changing the reaction temperature,the diameter of Cu(OH)2/CuO and nanowires can be controlled,and then the pore size of the Cu(OH)2/CuO ultrafiltration membrane can be adjusted to evaluate its rejection performance.The ultrasonic method was used to study the characteristics of Cu(OH)2/CuO ultrafiltration membranes which were reassembled after ultrasonic dissociation.X-ray diffractometer,field emission scanning electron microscope,high-resolution transmission electron microscope,and atomic force microscope systematically characterize the microstructure,phase composition,surface morphology,and strength of the membrance.The rejection performance of the dye and the bacteriostatic and bactericidal properties of the membrane were evaluated by the dye rejection test and the bactericidal experiment of the membrance,respectively.The results show that:(1)The diameter of the synthesized Cu(OH)2 nano wires is about 10nm and the length exceeds 30?m.It will spontaneously converge into a bundle,and the diameter of the nanowires bundles can reach 50-400nm.By increasing the reaction temperature,the diameter of the corresponding nanowires bundle increases,and the pore size of the Cu(OH)2 membrance also increases.The rejection experiments showed that the rejection coefficients of three Cu(OH)2 membrances(25??30??35?)for methyl blue were 100%,100%,and 98%respectively;and the rejection coefficients for methylene blue were 100%,52%,0%.At 0.1 MPa,the pure water fluxes of three Cu(OH)2 membrances are 58.9?133.7?159.2 Lh-1m-2.(2)The Cu(OH)2 ultrafiltration membrane has a multilayer structure,and each single-layer membrane is thick nanowires bundles wrapping thin nanowires bundles which can achieve the effect of multiple filtering.Thus,a model of Cu(OH)2 nanowires spheres formed during the reaction was established.(3)The length of the synthesized CuO nano wires exceeds 3 0?m.CuO nano wires also spontaneously converge into nano wires bundles,and the diameter of the bundles ranges from 100 to 500 nm.The rejection coefficients of the CuO membrance for methyl blue and methylene blue were 100%and 0,respectively.At a pressure of 0.1 MPa,the pure water flux reached 127.2 Lh-1m-2.(4)By the method of ultrasonic dissociation in distilled water,the self-assembly performance of Cu(OH)2/CuO membrance after fracture was studied.The length of the nanowires bundles in the recombination Cu(OH)2 membrane was truncated to 5-10?m and the diameter was significantly thickened,reaching 200-500nm,and the rejection coefficient of methyl blue was above 96%.In the recombination CuO membrane,the length of the nanowires bundles is 5-10?m and the diameter is about 100 nm.The rejection coefficient of methyl blue reached 100%.The ultrasonic dissociation and recombination method realizes the recycling of Cu(OH)2/CuO membrance,and provides a new method for energy saving and environmental protection of film materials.(5)The sterilization rate of Cu(OH)2/CuO membrance to staphylococcus aureus and escherichia coli is over 90%,which can effectively prevent the biological pollution of the membrance and the secondary pollution of purified water,and increase the service life of the membrance.