Preparation Of A New Type Of Antibacterial Activated Carbon By Inorganic Gel Method

In this paper, a new type of antibacterial activated carbon was made by using powder or particle activated carbon as raw material, using clinker as gelling agent, using nano Ag/TiO2 or its granulated product as antibacterial material. In the test, the influence of different kinds of antibacterial agents as well as their additive amount were mainly discussed, and the adsorption capacity was measured. The antibacterial property was measured by Halo Test both with direct viable count method(DVC); the adsorption capacity was measured by the Iodine adsorption number. The simulation adsorption effect was measured by adsorption number of Formaldehyde and Benzene; sample’s compression strength was measured as well as its porosity density and water-adsorption ratio; the microstructure of material were characterized by field emission scanning electron microscopy(FSEM); the recycling antibacterial experiment was investigated preliminarily. The sample’s properties were improved by external wrapping granulation technology. Compared with the other antibacterial activated carbon material, this method has many advantages such as low costs, simple process, high strength, superior adsorption performance and ideal antibacterial property, especially.Compared with nano Ag/TiO2 as antibacterial material, its granulated product has better performance in Halo Test. However, there are similar antibacterial property in direct viable count method and physical property as well. Being considered comprehensively, nano Ag/TiO2 is better antibacterial material as to its easy access to obtain. Experiments show that powder activated carbon is suitable adsorption material because of its better adsorption capacity, compression strength, porosity density and water-adsorption ratio compared with particle activated carbon.The optimum ingredients of sample are 60wt% of powder activated carbon,32wt% of clinker and nano Ag/TiO2 of 8wt%. Sample’s initial antibacterial ratio of E. coli and Sarcina lutea was 96.88% and 99.50%, respectively. The Iodine adsorption capacity is 416.56 mg/g. The Benzene and Formaldehyde adsorption value are 221.53 mg/g and 238.63 mg/g,respectively.The compression strength is 12.74 MPa. The porosity density and water-adsorption ratio are 47.92% and 40.07%, respectively.Recycling antibacterial experiment shows that the optimum sample’s antibacterial efficiency maintains 90% above during twenty cycling counts. SEM analysis shows that granalated products of nano Ag/TiO2 are distributed in powder or particle activated carbon matrix independently. Nano Ag/TiO2 material is evenly distributed in powder activated carbon while it’s covered over particle activated carbon matrix.External wrapping granulation experiment proves that nano Ag/TiO2 directly wrapped over sample leads to antibacterial material fast washed away, which is wasteful. The clinker in wrapping material can help it wrapped over sample while PVA can help improve wrapping material’s porosity structure and adsorption capacity. The experiment shows that wrapped sample has a better antibacterial property. The optimum wrapping ingredients are 90wt% of nano Ag/TiO2,5wt% of clinker and 5wt% of PVA. The antibacterial ratio of E. coli and Sarcina lutea in one hour is 65.1% and 72.84% respectively while 100% in four hours.