Evaluation of the influence of lipophilic extractive residues on dissolving pulp quality parameters by partial least squares method of chemometrics
Nordic Pulp and Paper Research Journal
University of Dar Es Salaam, Chemistry Department, PO Box 35061, Dar es Salaam, Tanzania; University of South Africa, College of Science Engineering and Technology, Nanotechnology and Water Sustainability Research Unit, UNISA Science Campus, Florida, Roodepoort, Johannesburg, South Africa; Department of Applied Chemistry, University of Johannesburg, South Africa; School of Chemistry, University of KwaZulu-Natal, Durban, South Africa
Dissolving pulp samples collected from the various pulping stages of the acid-bisulphite process were analysed for the lipophilic extractive residues as well as their effects and influence on the quality parameters of dissolving pulp were evaluated. The results obtained using the partial least squares (PLS) regression model showed that sterols, fatty alcohol, saturated and unsaturated fatty acids significantly influenced/affected the viscosity, Kappa number and carbohydrates in the pulp. The PLS model clearly separated the analysed pulp in terms of the species of the raw materials and pulping stages. Furthermore, it was observed that lipophilic extractives are negatively correlated to the yield of α-cellulose. Sterols, fatty acids and alcohols negatively influenced glucose in pulp, while xylose was found to be positively correlated to these components. Generally, the components of lipophilic extractives that have a major influence on the quality parameters were found to be sterols and saturated fatty acids.
Alcohols; Dissolution; Fatty acids; Lipids; Pulp materials; Quality control; Regression analysis; Saturated fatty acids; Unsaturated fatty acids; Chemometric method; Dissolving pulp; Fatty alcohols; Lipophilic extractives; Partial least square (PLS); Partial least-squares method; Partial least-squares regression; Quality parameters; Least squares approximations