Drainage and retention enhancement of a wheat straw-containing pulp furnish using microparticle retention aids

Abstract

The usage of non-wood pulps in furnishes for the production of various paper grades is a real alternative for the substitution of wood pulp in papermaking. In terms of the papermaking process, the main limiting factor for non-wood pulp utilization is poor dewatering. This problem can be partially solved by means of retention aids, and the modern microparticle-based retention aids are very promising for this application. In this study the main aim was to characterize how the microparticle retention systems affect the retention, dewatering, and formation of a non-wood pulp furnish and how these effects and mechanisms differ when compared to normal wood pulp. The performance of several commercially available retention aids was studied by making dynamic sheet forming tests for reference and an organosolv wheat straw furnish. The emphasis in the experiments was on drainage enhancement. The maximum drainage gain obtained with the bentonite-CPAM retention aid system was about 5%. Despite the improved drainage, dewatering of the reference furnish was better than for the non-wood containing furnish.

Towards bioproduction of poly-α-olefins from lignocellulose

“…For example, hydrolytic pretreatment of lignocellulose results in high molecular weight lignin containing up to 15% of residual cellulose. 23 Furthermore, bioprocessing of softwoods is more challenging compared to the processing of hardwoods or agricultural biomass due to higher lignin content (up to 30%), smaller pore size and lower amount of acetylated groups derived of hemicellulose. 24,25 However, in the Northern hemisphere softwoods provide a major perennial source for bioprocesses.…”

Catalytic Strategies Towards Lignin-Derived Chemicals

“…To increase the fractionation efficiency during soda-pulping, anthraquinone is often used, because it can act as a redox shuttle to promote ether bond cleavages (reductive) and stabilize the carbohydrate fraction (oxidative) [61,68]. A major advantage of the soda pulping process is the production of a more valuable sulphur-free lignin, thus avoiding catalyst poisoning or bad odors (often linked to sulphur) during downstream lignin processing [63,69].…”

Controlling Surface Hydrophobicity of Cellulose-Lignin Composite Coatings

“…Cellulose and lignin are well known biopolymers and belong to the most abundant natural substances [1]. Cellulose is mainly obtained from wood pulp via Kraft pulping (also known as the sulfate process) or by a more environmental friendly alternative pulping technique known as the organosolv process [2].…”