Preparation Of Porous Ceramic Suspension And Surface Modification

Suspended porous carrier mainly uses plastic material,It is expensive, smoothsurface (the surface treatment), biological activity and chemical resistance, thermalstability and other defects,Thus under certain restrictions of application. While theordinary ceramic carrier is large, large power consumption.In this paper, by usingindustrial waste slag fly ash as the main raw material, using a high temperature foamdeveloped by the method of density and water close to the porous ceramic suspendedcarrier.In the process of test first on the basic formula to explore, to find a reasonablematerial, and then different factors, conducted a separate investigation and orthogonalexperiment.Experiments show that the formula for fly ash,60%,15%of kaolin, feldspar,calcite talc18%,2%, burned in5%of cases, by adding2%foaming agent (Na2SO4andMgCO31%),On the reasonable firing curve, at1260degrees C. the firing temperature,insulation30min, can be made to meet the requirements of the suspensions of porousceramic material, which has the following properties: the volume density of0.8~1.1g/cm3, apparent porosity rate of more than50%, the compressive strength of2.5~3MPa.With the domestic and foreign similar products, biological activity and chemicalresistance, good thermal stability, large specific surface area, the suspensionperformance.In addition, heterogeneous condensation, repeatedly suspended ceramic coatingmethod modified positively charged surface, and adsorption properties of modifiedceramic, iron load, bulk density, apparent porosity, compressive strength, modification ofsurface morphology， surface electrical and phase composition of coatings werecharacterized by analysis. The best modification conditions were determined bymethylene blue adsorption experiments as follows:1mol/L of ferric chloride, calcinationtemperature650℃, roasting time3h. Prepared under this condition, the modifiedceramic removal rate of86.3%methylene blue, is3.1times that of unmodified ceramic.The test showed that the modified ceramic granule was covered with a layer iron oxidewith uneven thickness. The main phase of iron oxide layer was α-Fe2O3which exhibitedporous structures.Magnetic/carbon modification conditions: glucose and KOH solution impregnationratio is4, the carbonization temperature400℃，activation temperature850℃, activationtime1h, magnetic powder added10%. The modified suspension ceramsite of methyleneblue on removal rate up to88.1%, is3.15times that of unmodified ceramic. The resultsshowed that: modified ceramic surface layer thickness uneven magnetic/carbon coating,has developed specific surface area and high void structure, facilitate the separation and recycling.