Filtering method for chemical analysis

Abstract

The invention particularly relates to a filtering method for chemical analysis. According to the technical scheme, a U-shaped pipe is full filled with the degreasing cotton in a fluffy manner to obtain a filtering pipe, the inner diameter D of the U-shaped pipe ranges from 3 mm to 5 mm, and the length L ranges from 150 mm to 200 mm; then using a to-be-filtered aqueous solution or the distilled water to completely wet the degreasing cotton filled in the filtering pipe, putting one end of the filtering pipe into a container for receiving the filtrate, and inserting the other end of the filteringpipe into the bottom of the container filled with a to-be-filtered aqueous solution, the bottom of the container filled with the to-be-filtered aqueous solution is higher than the final liquid levelof the container for receiving the filtrate; and finally, after the to-be-filtered aqueous solution is completely filtered, the filtrate and a precipitate are separately obtained. The method has the characteristics of being simple to operate and having small pollution, no filter paper blockage and no precipitation and filter penetration.

Description

technical field [0001] The invention belongs to the technical field of solution filtration. In particular, it relates to a filtering method for chemical analysis. Background technique [0002] Many filtration operations are involved in the field of chemical composition analysis. Its purpose is to separate the insoluble matter in the solution from the solution to obtain a solution of insoluble matter and a fixed concentration or a solution without a fixed concentration. [0003] When a solution with a fixed concentration is required, use dry filtration (YB / T 190.3-2001 Chemical Analysis Method for Continuous Casting Mold Flux - Determination of Calcium Oxide Content by EGTA Titration). The so-called dry filtration means that the filter paper, funnel and receiving container involved before filtration are all dry, and the concentration of the solution obtained by filtration is the same as that before filtration. The specific operation is to fold the filter paper into a 90-de...

AI Technical Summary

Problems solved by technology

[0005] Since there are particles in the sediment whose particle diameter is similar to or smaller than the pore size of the filter paper, the particles smaller than the pore size of the filter paper will pass through the filter, and the filtration speed in the later stage of filtration will often decrease, and sometimes the filter pores of the filte...