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Journal articles
Magazine articles
Open Access
Lignin-based resins for kraft paper applications, TAPPI Journal November 2019

ABSTRACT: We investigated miscanthus (MS) and willow (W) lignin-furfural based resins as potential reinforce-ment agents on softwood and hardwood kraft paper. These resins might be sustainable alternatives to the commercial phenolformaldehyde (PF) resins. Phenol is a petrochemical product and formaldehyde has been classified as a carcinogen by the U.S. Environmental Protection Agency. The lignin used in this study was derived from hot water extraction (160ºC, 2 h) of MS and W biomass, and may be considered sulfur-free. These biorefinery lignins were characterized for their chemical composition and inherent properties via wet chemistry and instrumental techniques. The resin blends (MS-resin and W-resin) were characterized for their molecular weight, thermal behavior, and mechanical properties. Mechanical properties were measured by the resin’s ability to reinforce softwood and hard-wood kraft papers. The effect of adding hexamethylenetetramine (HMTA), a curing agent, to the resin was also examined. Mixtures of PF and lignin-based resins were investigated to further explore ways to reduce use of non-renewables, phenol, and carcinogenic formaldehyde. The results show that lignin-based resins have the potential to replace PF resins in kraft paper applications. For softwood paper, the highest strength was achieved using W-resin, without HMTA (2.5 times greater than PF with HMTA). For hardwood paper, MS-resin with HMTA gave the highest strength (2.3 times higher than PF with HMTA). The lignin-based resins, without HMTA, also yielded mechanical properties comparable to PF with HMTA.

Journal articles
Magazine articles
Open Access
Fate of phosphorus in the recovery cycle of the kraft pulping process, TAPPI Journal March 2020

ABSTRACT: The accumulation of nonprocess elements in the recovery cycle is a common problem for kraft pulp mills trying to reduce their water closure or to utilize biofuels in their lime kiln. Nonprocess elements such as magnesium (Mg), manganese (Mn), silicon (Si), aluminum (Al), and phosphorus (P) enter the recovery cycle via wood, make-up chemicals, lime rock, biofuels, and process water. The main purge point for these elements is green liquor dregs and lime mud. If not purged, these elements can cause operational problems for the mill. Phosphorus reacts with calcium oxide (CaO) in the lime during slaking; as a result, part of the lime is unavailable for slaking reactions. The first part of this project, through laboratory work, identified rhenanite (NaCa(PO4)) as the form of P in the lime cycle and showed the negative effect of P on the availability of the lime. The second part of this project involved field studies and performing a mass balance for P at a Canadian kraft pulp mill.

Journal articles
Open Access
Measurement of strains in a paper tensile specimen using computer vision and digital image correlation-Part 2: Tensile specimen test, TAPPI JOURNAL April 1988 88APR153

Measurement of strains in a paper tensile specimen using computer vision and digital image correlation-Part 2: Tensile specimen test, TAPPI JOURNAL April 1988

Journal articles
Open Access
Sintering of fireside deposits and its impact on plugging in kraft recovery boilers, TAPPI JOURNAL April 1988 88APR109

Sintering of fireside deposits and its impact on plugging in kraft recovery boilers, TAPPI JOURNAL April 1988

Journal articles
Open Access
The role of diffusion during initial delignification of alkaline pulping, TAPPI JOURNAL April 1988 88APR145

The role of diffusion during initial delignification of alkaline pulping, TAPPI JOURNAL April 1988

Journal articles
Open Access
Automatic winder slitter positioning using a programmable logic controller, TAPPI JOURNAL August 1988

Automatic winder slitter positioning using a programmable logic controller, TAPPI JOURNAL August 1988

Journal articles
Open Access
Further comments on a visual study of pulp floc dispersion mechanisms, TAPPI JOURNAL 1988

Further comments on a visual study of pulp floc dispersion mechanisms, TAPPI JOURNAL 1988

Journal articles
Open Access
TAPPI survey of 1987 incomes, TAPPI JOURNAL August 1988

TAPPI survey of 1987 incomes, TAPPI JOURNAL August 1988

Journal articles
Open Access
The use of proton NMR for pitch analysis-a case study, TAPPI JOURNAL August 1988

The use of proton NMR for pitch analysis-a case study, TAPPI JOURNAL August 1988

Journal articles
Open Access
A rapid method for the qualitative analysis of plastic and "sticky" contaminants by pyrolysis-gas chromatography, TAPPI JOURNAL February 1988 88FEB109

A rapid method for the qualitative analysis of plastic and "sticky" contaminants by pyrolysis-gas chromatography, TAPPI JOURNAL February 1988