Study Of The Performance Of Filter-Paper Adding In Active-Carbon And Silica-Gel

Active-carbon-silica-gel-purifying-filter-paper is a kind of filter paper which contains active carbon particles and silica gel particles and which can absorb pigment as well as fat. When testing the pesticide residue of crops, It is used to get rid of foreign substances such as fat and pigment that may interfere with the test,increase efficiency and reduce considerable cost.Firstly, this thesis studies the influence of fibre state on active-carbon-purifying-filter-paper, relationship between active carbon quantity and the rate of recovery of pesticide as well as depigmenting effect. Research on depigment effect and active-carbon-purifying-filter-paper has been done from such perspectives as state of fibre, physical performance, filtering performance, remains of active carbon, active carbon quantity the rate of recovery of pesticide. The results show that: the best material to make active-carbon-purifying-filter-paper is unbleached coniferous wood pulp,the best degree of making beating is 26° SR and adding 4gof active carbon can well satisfy the need to get rid of the pigment in crops when testing the pesticide residue.Secondly,this thesis studies the influence of degree of making beating on silica-gel-purifying-filter-paper,and the influence silica gel quantity on the rate of recovery of pesticide,the relationship between silica gel quantity and defatting effect, active carbon and the rate of recovery as well as depigmenting effect.Research has been done from such perspectives as physical performance, filtering performance, remains of silica gel, devide out of fat, and the rate of recovery of pesticide. The results show that: the degree of making beating is 25° SR and adding 5g of silica gel quantity ,the fat of soy bean can be gotten rid of. This show adding 5g of silica gel quantity silica-gel-purifying-filter-paper can get rid of the fat of crops which fat quantity is lower than 18.4%. And it show that silica gel absorbs little endousulfan pesticide, the rate of recovery of pesticide is over 90%.Thirdly, active carbon is mixed with silica gel and put into coniferous wood pulp fibre to form the active-carbon-silica-gel-purifying-filter-paper. The results show that: if active carbon quantity is lower than 5g and silica gel quantity is lower than 7g, the rate of recovery of pesticide of active-carbon-silica-gel-purifying-filter-paper is over 80%.Different depigmenting capacity and defatting capacity have been measured when added different quantity of active carbon or silica gel.It is be founded that the effect of active carbon quantity on defat is litter and defat is chiefly dependent on silica gel,and the effectof silica gel quantity on depigment is litter and depigment is chiefly dependent on active carbon.Lastly, a rough estimation is made on the cost of active-carbon-silica-gel-purifying-filter-paper, and the result tells us that: it takes 0.80 yuan to manufacture a piece of active-carbon-silica-gel-purifying-filter-paper with a diameter of 0.2m, and this is far lower than the cost of adding post.