Study On Synthesis And Application Of Porous Calcium Phosphate

With the improvement of people's life level, People' demands on beautifying house and improving working environment enhance continually. During the indoor decoration, some material release formaldehyde, benzene, ammonia, volatile organic matters and so on, which pollute the indoor environment and intimidate people's health. Porous calcium phosphate has good adsorption property for deleterious gas, like formaldehyde and ammonia, as active carbon does. It will do good to family demand if fill it into paper material or, coat it onto the paper surface and make decorate paper out. So, this paper will emphasizing the preparation technology, adsorption property of porous calcium phosphate and, its utilization in paper making. The results are as follows:Using matter A as tore forming material to prepare porous calcium phosphate, the proper conditions are: n (Ca(OH)₂)/ n(H₃PO₄) =3:3, matter A addition 17%, sinter temperature 950℃; When using matter B as tore forming material, the proper conditions are: matter B addition 6%, n (Ca(OH)₂)/ n(H₃PO₄) =3:2.8, sinter temperature 1050℃.According to the specific area of porous calcium phosphate and its morphological analysis, porous calcium phosphate is a kind of coralloid granule with much surface limitation and interspace. matter A model has specific area of 50.57g/m² and, matter B model 70.59g/m².Except the physical adsorption effect to gas, to large extent, Special property and high specific area of porous calcium phosphate is up to its self property. It has good adsorption property to ammonia and formaldehyde, the adsorption level under the best condition for matter A model can be to 793.6 mg/g to ammonia and 489.62 mg/g to formaldehyde; for matter B model can be to 602.84 mg/g to ammonia and 658.71 mg/g to formaldehyde.In order to remain more porous calcium phosphate in paper, wet-end addition to prepare porous calcium phosphate deodour paper was studied. CPAM charge 0.025%-0.03%, silica aluminium partical charge 0.3% during silica aluminium aid/retention system can make retention of porous calcium phosphate over 90%, meanwhile, paper strength and other paper properties can meet using demand. Using more porous calcium phosphate in paper making, the result deodour paper will show better adsorption property accordingly. When the addition was 30%, deodour paper will show good adsorption for formaldehyde and ammonia gas. When addition was 90%, matter A model deodour paper has an adsorption level of 743.2 mg/g to ammonia, 310.4 mg/g to formaldehyde, matter B model deodour paper has an adsorption level of 436.5 mg/g to ammonia and 557.2 mg/g to formaldehyde.When porous calcium phosphate was coated onto the paper surface, using PVA as adhesive, ensure good combine strength between paint coatings and paper, at the same time, try to reduce the adhesive charge, improve solid content of paint coatings. Deodour paper prepared by...