A method for measuring the quantity of super absorbent polymers in post-consumer absorbent sanitary products
AssigneeFATER S.p.A.
InventorsTonino CARUSO, Patrizia IANNECE, Nicola D'ALESSIO, Melania MIGLIACCIO
Life of this patent
Estimating the term…
Abstract
A method is provided for measuring a quantity of super absorbent polymers (SAP) in a sample obtained from post-consumer absorbent sanitary products comprising at least one portion of a portion of cellulose and/or a portion of plastic in addition to a portion of SAP, said post-consumer absorbent sanitary products having been, preferably, previously subjected to at least one treatment comprising the separation of said portions; the SAP contained in said sample comprise linear polyacrylate polymers (LPA) and/or cross-linked polyacrylate polymers (CLPA).
Claims12
A method for measuring the quantity of super absorbent polymers (SAP) in a sample obtained from post-consumer absorbent sanitary products comprising at least one portion of a portion of cellulose and/or a portion of plastic in addition to a portion of SAP, said post-consumer absorbent sanitary products having been, preferably, previously subjected to at least one treatment comprising the separation of said portions,
- wherein the SAP contained in said sample comprise polymers of linear polyacrylate (LPA) and/or polymers of cross-linked polyacrylate (CLPA), the method comprising the steps of:
- a) contacting a first fraction of the sample with an aqueous solution containing a known quantity C0 of a water-soluble cation XY, and obtaining a suspension comprising a solid fraction and a liquid fraction,
- b) after a period of time T1, separating the solid fraction from the liquid fraction and measuring the residual quantity C1 of said water-soluble cation XY in said liquid fraction,
- c) calculating the difference C0-C1 between the known quantity C0 and the quantity C1 of the cation XY remaining after the time period T1,
- d) contacting a second fraction of the sample with a solution comprising a salt for a period of time T2 and obtaining a suspension comprising a solid fraction and a liquid fraction, wherein said salt promotes the passage of said water-soluble cation XY of metabolic origin and not already bound to the SAP into said liquid fraction,
- e) separating the solid fraction from the liquid fraction and contacting, for a period of time T3, the solid fraction with a solution comprising an acid for displacing said water-soluble cation XY of metabolic origin already bound to the SAP and promoting its passage into said solution,
- f) measuring the quantity CB of said water-soluble cation XY contained in said liquid fraction obtained in step d) after the period of time T2, and the quantity CH of said water-soluble cation XY contained in said aqueous solution containing an acid, preferably HC1, after the time period T3,
- g) calculating the difference CH - CB this difference being indicative of the quantity of said cation contained in the sample and derived from the metabolism and bound to the SAP,
- h) calculating the quantity of SAP contained in said sample as a function of the difference C0-C1 and of the difference CH-CB.
Dependencies are inferred from the claim text.