Study On Nano-composite Water Purifying Materials

The scarcity of water resource and the seriousness of water pollutionhave become the global problems. With the development of living conditionand industrialization, water pollution becomes serious increasingly and itleads to the decline of the quality of drinking water. If a man drinks or touchesthe polluted water in a long period, it will bring serious influence and do harmto man's health. It has been an important and pressing problem to purify waterwith waste water treatment, so people can drink clean and healthy water.The contaminations in the aqueous solutions, such as heavy metals,organic matter and bacteria, all do harm to man's health. The heavy metals inthe aqueous solutions mainly come from the drainage of industrial wastewater. Some diseases are relative to heavy metal ions in the aqueous solutions.With the development of exploitation,smelting, transaction and commercialmanufacture, heavy metals come into atmosphere, water and soil environmentmay cause serious environmental pollution. When the heavy metals of variouschemical state or conformation come into natural environment or ecosystem,they will exist, cumulate, transfer and engender harm. Heavy metal ions aredifficult to biodegraded or destroy. Biology ingests heavy metals fromenvironment, heavy metals may accumulate into the organism, hydrophyticplants and terricolous crops, then turn into human through the food chain,heavy metals do severe harm to human beings. So we attach important to thesource of heavy metals pollution, the treatment of waste water and thestandard of drained water increasingly. Most of the organic matters in theaqueous solutions have acute or chronic, direct or indirect noxious functions;some of them can even change the structures of DNA in human tissues. Thereare 117 kinds of the organic matters in drinking water; these matters causecancer, abnormality and mutation. Therefore to purify wastewater containingorganic matters is necessary. WHO has summarized that 80% of diseases andone third of death are caused by the polluted drinking water. So it is importantto remove bacteria in the aqueous solutions and let humans drink healthy andclean water. Now there are many waste water treatments and methods, most of them are applied in large scale system. Most of them are used to remove high concentration pollution but seldom aim at low concentration pollution. The conventional separation technologies consume vast chemical reagent, demand big place to experiment and cost a lot, then the chemical reagent may pollute the environment again and the separation technologies are not thorough, so the waste water can not reach the "Integrated Wastewater Discharge Standard GB8978-1996". To solve the problems above and satisfy the developing of the health consciousness and living condition, now we urgently need one kind of efficient and easy operated waste water treatment. Here we researched on the nano-composite water purifying material. By changing the raw and processed materials and the condition of the preparation, we continuously optimized the nano-composite water purifying material. The nano-aluminium powders have high react activity and big ratio surface area. By using its hydration reaction we prepared the nano-composite particles. In our experiment, we respectively chose fiberglass , microcrystalline cellulose,polyethylene fiber and activated carbon fiber as the carrier of the nano-composite particles, and designed a series of the comparative experiments. We prepared the nano-composite water purifyingmaterial using the four kinds of carries above, and we examined thematerials'characterization through the experiment of removing thecontaminations in the aqueous solutions. The results showed that thenano-composite water purifying materials made by the carrier of fiberglasshas the maximum saturated adsorption. It show that fiberglass is better thanthe other carriers,it can better fix the nano-composite particles, and thematerial's absorption capability is biggest. Because the adsorption capabilityof the activated carbon fiber felt, we used it as the underlay of thenano-composite water purifying materials. Hereto we ascertained theselection of the raw and processed materials of the materials. To optimize thematerial's adsorption capability, we changed the temperature of the reactionand the conductions of the reaction to prepare the nano-composite waterpurifying materials, then we had a lot of comparative experiments purifyingwater, at last we drew a conclusion that the best conduction to preparematerial is that using the ultrasonic precipitation process to prepare thenano-composite particles, then fix them on the fiberglass, at last we use theactivated carbon fiber felt as the underlay, through rolling and desiccating wecan prepare the water purifying materials. Under the above conditions weprepared the best water purifying materials, they can thoroughly remove thelow concentration of cadmium ion from aqueous solutions, and now thematerials have the maximum saturated adsorption and super adsorptioncapability. The saturated adsorption is an important standard to evaluate thematerial's adsorption capability, we use the Thomas model to simulate andcalculate the adsorbents'saturated adsorption.