Type and Selection of Quantitative Filter Paper
Quantitative filter paper, as ash-less grade filter paper, is usually used in quantitative analysis and gravimetric analysis test. During the operation, it would be subjected to special treatment procedures, which could effectively resist certain chemical reactions and prevent the generation of impurities.
Types of quantitative filter paper
Generally, there are three types of quantitative filter paper to meet the clients’ various demands, including ashless grade, hardened low-gray grade, and hardened ashless grade. The ash content of ashless grade filter paper is about 0.007%. Based on the different specifications, it could be applied in different industries, such as analysis of water-suspended particles in the paper industry, Blaine particle detection in the cement industry, petroleum sediment detection in the chemical industry and etc.
The hardened low-gray grade filter paper is especially suitable for Buchner funnel filtration, whose ash content is about 0.015%. The hardened ashless grade one is processed by acid hardening treatment, which is featured for its high wet strength and chemical resistance with about 0.006% ash content. It could be used for the analysis of hydroxide after precipitation of concentrated alkali, and the analysis of coarse particles and gel precipitates as well.
Selection of quantitative filter paper
According to the features of the samples, all the three types of quantitative filter paper needs to be chosen carefully. If the analysis of strong acid or alkali intends to be conducted, the hardened ashless grade filter paper is the first choice. Otherwise, the ashless grade one could be adopted.