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Compared with traditional petroleum-based foam materials, cellulosic foam materials have significant advantages in terms of economy and environmental protection. However, the traditional cellulose-based foams have some problems such as high energy consumption in the preparation process. In this study, the recycled pulp foam (RPF) with ultra-light density (12.69 kg/m3 ~ 13.83 kg/m3) and high porosity (99.07 % ~ 99.15 %) was prepared by mechanical stirring using waste corrugated cardboard as the main raw material and further hydrophobically modified using rosin. The prepared r-RPF foam has excellent hydrophobicity with the water contact angle remaining 132.9° after 20 s. In addition, the rosin coating enhances the mechanical properties of r-RPF, and the stress of r-RPF at 50 % strain is increased by 97 %. It should be noted that after rosin treatment, the compressive strength and elasticity of r-RPF were improved. The r-RPF was stable in water and had a high oil adsorption capacity (7.8 to 28.13 g/g), which had the potential to treat current oily wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: High-performance liquid chromatography (HPLC) coupled to an evaporative light scattering detector was used to quantitatively determine glucose and cellobiose in hydrolyzates from the production of cellulose nanofillers from modified lignocellulosic materials. Prevail Carbohydrate ES 5μ column proved more suitable for achieving the chromatographic separation of the model pulp hydrolyzate into its constituent sugars than the YMC-Pack Polyamine column. Linear calibration curves for the various sugars in the mixtures were developed. Glucose and cellobiose were clearly detectable in pulp hydrolyzates obtained from enzyme-mediated hydrolysis of recycled pulp, pine and hardwood dissolving pulps. Finally, the amount of glucose in the pulp hydrolyzates was generally higher than cellobiose. [Copyright &y& Elsevier]

This study examined the production of cellulose nanocrystals from microcrystalline wood cellulose, Avicel and recycled pulp of wood pulp using sono-chemical-assisted hydrolysis. Two hydrolysis systems: deionized water and maleic acid were evaluated. In deionized water, Avicel produced cellulose nanocrystals with average diameter of 21±5nm (minimum 15nm and maximum 32nm). Cellulose nanocrystals from recycled pulp were not distinctively spherical and had an average diameter of 23±4nm (minimum 14nm and maximum 32nm). Maleic acid (50mM) sono-chemical assisted hydrolysis of Avicel at 15°C and 90% power output for 9min produced cellulose nanocrystals which were cylindrical in shape and were of dimensions, length 65±19nm and width 15nm. [Copyright &y& Elsevier]

Abstract: The composition, nanostructure and distribution of extractives on fiber surfaces of a birch bleached kraft pulp (BKP) and a recycled deinked pulp (DIP) was investigated using X-ray photoelectron spectroscopy (XPS or ESCA), time-of-flight secondary ion mass spectrometry (ToF-SIMS) and atomic force microscopy (AFM). Effects of different extraction methods on the fiber surfaces were also investigated, in addition to the analyses of extractives by gas chromatography (GC). Traces of surface extractives were observed by XPS, ToF-SIMS and AFM in the BKP after extraction using an acetone–phosphate method (AcP). This method improved the extraction yield of palmitic and stearic acids in DIP, but the removal of surface extractives was not as effective as for BKP. Contaminants, identified as siloxanes and phthalates by ToF-SIMS were observed for DIP and BKP, even after AcP extraction. Stearic acid and its calcium salts were found to form aggregates with a diameter of 100–500nm, while oleic acid formed a uniform layer. Estimations of extractive surface coverage by XPS were consistent with qualitative observations by ToF-SIMS and AFM. The combinations of different techniques strengthen the value of XPS, ToF-SIMS and AFM for fiber surface investigation. [Copyright &y& Elsevier]

Deinking of recycled pulps is an important operation intended to provide pulps appropriate for making paper and paperboard products from recycled wastepaper. Conventionally, deinking of recycled pulp is conducted in a flotation cell equipped with an agitator. We have investigated the applicability of a new flotation cell based on a column without an agitator present to accomplish the deinking of typical wastepaper feedstocks and also a feedstock consisting of rejects from a conventional deinking cell. Experimental results on the deinking operation indicate that it is possible to achieve deinking of a mixture of photocopier and laserprinted paper in the column flotation cell. The performance of the column, as measured by the resultant pulp's brightness and ink particle size distributions, is comparable to that of a conventional laboratory cell which incorporates severe agitation regimens. Thus, it is found that the agitator can be eliminated by using the column flotation design which could yield significant electrical energy savings in addition to savings in capital costs and other operational and maintenance costs. A series of deinking experiments were also performed on a feedstock consisting of rejected waste obtained from a conventional cell in a pilot plant. We found that deinking of the rejected waste could yield significant usable fiber. This indicatesthe potential of the column flotation technique in enhancing the reuse of a waste component thus reducing the volume of deinking waste rejected into the environment. [ABSTRACT FROM AUTHOR]