Preparation, Characterization Of Holding Ag Anti-bacteria Ball In Drinking Water System

The health security of drinking water is the basic requirement. Drinking water of low quality will lead to serious consequences. Drinking water of residents confronts serious secondary pollution in the transport and storage. This study aims to develop a kind of new holding nano-Ag anti-bacteria balls which are low-cost, easy to use and efficient antibacterial effect. These anti-bacteria balls are applied to tanks in residential buildings, to improve the quality of drinking water.In this study, CTS-SiO2 blend films, CTS-SiO2-Ag+ blend films and CTS-SiO2-Ag blend films was prepared based on chitosan by blend reaction, and study the physical and chemical properties and antibacterial properties of these blend films. On this basis, using silicone as the carrier of the ball, and prepare the surface coating CTS-SiO2-Ag layer of the anti-bacteria balls with excellent mechanical properties, favorable, stability and continuous antibacterial properties. This paper study the influence of blend films and anti-bacteria balls' properties on the reaction temperature of experiment, the reaction time of experiment, the input amount of Ag+ and heat treatment condition, choose the best preparation method finally. At the same time, this study characterize the blend films by using IR and SEM.The results show that, there are strong hydrogen bonds between SiO2 and the CTS, and favor the CTS blend SiO2 reaction. There are coordination bonds between Ag+ and amino(-NH2) in the molecular structure of CTS, enhanc the cross-linked extent of blend films. CTS-SiO2 blend films compared with pure CTS films structure is more compact, surface is smoother. The scatter properties and size of nano-Ag particle in CTS-SiO2-Ag blend films lie on the input amount of Ag+:fewer input amount of Ag+, the nano-Ag particle's size is smaller, scattered better; more input amount of Ag+, the nano-Ag particles'size is larger, scattered more badly. The antibacterial properties of surface coating CTS-SiO2-Ag layer anti-bacteria balls lie on nano-Ag particles' size and scatteration degree:the smaller the particle size, the higher the scatteration degree, the better antibacterial properties; the greater the particle size, the lower the scatteration degree, the worse the antibacterial properties.Heat treatment can improve the cross-linked extent of function layer, on the one hand, it can improve the mechanical properties of function layer, on the other hand it can prevent losing of nano-Ag in function layer, effectively promote the antibacterial properties of anti-bacteria balls. On the preparation process of anti-bacteria balls, first heat treatment temperature is 60℃, second heat treatment temperature is 50℃, first& second heat treatment time is 2 h conformably.Determined the best method by single-factor test preparation surface coating CTS-SiO2-Ag layer anti-bacteria balls:the blend reaction temperature is 30℃, the blend reaction time is 2 h, drying temperature is 30℃, with concentrations of 80% hydrazine hydrate N2H4·H2O as a reducing agent, at room temperature and reaction time is 6h. When SiO2 concentration of massρSiO2=2%, CTS concentration of massρCTS=2.5%, Ag+ concentration of volumeφAg+(0.01mol/L)=3%, in the CTS-SiO2-Ag functional layer, choosing silicone as a carrier, can be prepared surface coating CTS-SiO2-Ag layer anti-bacteria balls with excellent mechanical properties, favorable, stability&continuous antibacterial properties, its mass loss rate P=2.11%, antibacterial rateψ=98.8%.