TH22162A - Methods for determining the number of chemical additives in pulp and paper? - Google Patents

Abstract

The method for determining the quantity of reactive and retaining chemical compounds selected from a group comprising wetting strength enhancers, starches and stabilizers, hydrophobics, and debonding agents in pulp and/or paper involves (I) developing a standardized model by (I.a) recording the absorption, reflection, or projection spectrums of reference samples containing known quantities of reactive and/or retaining chemicals to develop study sets; (I.b) processing the unprocessed spectrum data to reduce noise and adjust for shift and scattering of light; (I.c) performing chemometric analysis of the data to process the study sets; and (II) quantifying the quantities of reactive and/or retaining chemicals on pulp and paper that are unknown. Selected from groups containing wet-acting, starch and fixing agents, hydrophobic, and debonding agents, by recording absorption, reflection, or projection spectrums according to method (I.a) from pulp and/or paper of unknown quantities of reactive and/or fixing agents of such pulp and paper; process the untreated spectrum data obtained according to method (I.b); and use the developed benchmarking model to process the data (I.a) from paper and/or unknown quantities of reactive and/or fixing agents of such pulp and paper; process the untreated spectrum data obtained according to method (I.b); and use the developed benchmarking model to process the processed data.

Claims (18)

1. A method for determining the quantity of selected performance-enhancing chemicals from a group of wetting, starch and fixing agents, hydrophobic and deboning agents that react with and/or remain with cellulose fibers in pulp and/or paper, which consists of (I) the development of a standardized model by (I.a) recording the absorption, reflection or projection spectrums of reference samples of paper containing the following performance-enhancing chemicals. (I.b) Process the raw spectral data to reduce noise and adjust for drift and diffuse light scattering. (I.c) Perform chemometric analysis of the data to process the study set. and (II) Quantify the reactive and/or persistent unknown pulp and paper conditioning chemicals selected from a group of wet strength enhancers, starches and stabilizers, hydrophobics, and debonding agents by recording absorption, reflection, or projection spectra according to the method. (I.a) From paper and/or unknown quantities of chemicals, enhance the reactive and/or persistent properties of the pulp and paper; process the untreated spectrum data obtained according to method (I.b); and use the developed benchmark model against the processed data. 2. The method under claim 1 is specific in that it performs spectral recording of absorption, reflection, or emission in the wavelength range of 200 nanometers to 400 micrometers. The range of 800 nanometers to 2500 nanometers should be selected. 3. The method under claim 1 is specific in that it processes the spectrum data using the Kubelka-Munk transform (chemical formula), where Rik is the apparent absorption at wavelength k, Aik is the transformed absorption at wavelength k, and index i is the spectrum sample. 4. The method under Claim 1 is characterized by performing processing on spectrum data using Multiplicative Scatter Correction (chemical formula), where Rik is the apparent absorption at wavelength k, Aik is the transformed absorption at wavelength k, ai is the least squares approximation of the intercept variable, and bi is the least squares approximation of the slope variable, index i is the number of sample spectrums available, and index k is the wavelength available. 5. The method described in Claim 1 is specific in that it processes spectrum data using a Fourier transformation. 6. The method under Claim 1 is specific in that it processes spectrum data using derivatives up to the fourth level. 7. The method described in Claim 1 is specific in that it processes spectrum data using Standard Normal Variate transformation. 8. The method for selecting a wet-strength compound for paper, using one of the methods outlined in claims 1-7, shall have specific characteristics and be analyzed using Discriminant Analysis. 9. One of the methods under claims 1-7 has specific characteristics and performs data analysis using Multilinear Regression Analysis techniques. 10. One of the methods under claims 1-7 has the specific characteristic of analyzing data using Principal Component Analysis techniques. 11. One of the methods under claims 1-7 has the specific characteristic of analyzing data using Principal Components Regression techniques. 12. Any of the methods under claims 1-7 have a specific characteristic of analyzing data using the Partial Least Squares technique. 13. Any one of the methods under claims 1 through 12 shall be used to determine the amount of reactive nitrogen and/or the amount of residual nitrogen in the nitrogen-containing enhancer. 14. Any one of the methods under Reputations 1 through 12 shall determine the quantities of alkyl ketene dimer and rosin that react and/or remain. 15. Any one of the methods under Reputations 1 through 12 shall determine the quantities of reacting and/or residual alkyl succinic acid and alkyl carbamoyl chloride. 16. Any one of the methods under Reputations 1 through 12 shall determine the quantity of quaternary fathiamine and fathiamine oxide remaining. 17. Methods for maintaining the control program and quantifying the reactive and/or residual performance chemicals on selected paper and pulp from groups containing wet strength enhancers, starches and stabilizers, hydrophobics and deboning agents in paper or pulp to monitor any changes in them and provide input data for control to ensure that the additives are present at appropriate levels using the methods specified in Claims 1 through 16. 18. The method under one of the preceding claims has the specific characteristic of performing the analysis of data under one of the claims 8-16 on processed spectrum data obtained from pulp and/or paper with an unknown quantitative performance-enhancing chemical. (18 claims, 3 pages, 5 figures)