Pulp - Determination of cellulose nanocrystal sulfur and sulfate half-ester content

This document describes the laboratory determination of fibers by inductively coupled plasma optical emission spectroscopy (ICP-OES) and conductometric titration, respectively. Steps to determine the content of elemental sulfur and sulfate half-ester in plain nanocrystals (CNCs).
This document applies to the following types of cellulose nanocrystals:
a) With monovalent counterions (especially hydronium ions and sodium ions);
b) Dispersions that have not been dried or are redispersed from a dry state;
c) It is obtained by hydrolyzing cellulose raw materials in nature through sulfuric acid or hydrolyzing and then acidifying with sulfuric acid.