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Excess lignocellulose fines in some fiber processing mills cause issues and hurt product quality. To use this type of biomaterial as a resource, surplus fines can be separated and dissolved with solvents for further transformation. Therefore, 1-butyl 3-methyl imidazolium chloride ionic liquid (IL) was used as a powerful green solvent for a rapid dissolution process. However, a low degree of polymerization (DP) of the cellulose in fines and the effects of lignin content and its structure on the process and film properties are controversial subjects. This study demonstrated that the three dimensional structure of lignin did not permit the raw bagasse fines (prior to pulping) to dissolve in the IL even after several hours. However, following d
In recent years, many studies have been carried out on the use of cellulose nanofiber (CNF) produced from virgin fiber as a strengthening agent for improving the physical and mechanical properties of paper, while the use of CNF isolated from bleached virgin fiber is not necessary or reasonable for many recycled/impure products. In this due, novel lignocellulose nanofiber (LCNF) was produced from inexpensive recycled old corrugated container pulp by the ultra-fine grinding technique. The diameter of the resulted LCNF was in the range of 10–80 nm, while the cellulose crystallinity index and crystallite size reduced during the process to 49% and 4 nm, respectively. Regarding the chemical composition of LCNF, no significant change was observe
The application of chitosan biopolymer with and without nanoparticles in the papermaking process was investigated. The effect of the chitosan’s molecular weight on its interaction with silica nanoparticles in recycled old corrugated container pulp was studied. Initially, the nanosilica particles were analyzed via atomic force microscopy and scanning electron microscopy, which confirmed the spherical shape of the silica nanoparticles with diameter less than 5 nm. Dynamic light scattering method was used to determine the zeta potential and the hydrodynamic radius of the chitosan with different molecular weights. Infrared spectroscopy was used to show the possibility of hydrogen bonding between the chitosan and the nanosilica. The results sh
As a prospective raw material, lignin containing papermaking fibers can be easily recycled, dissolved with proper solvents and reused. However, in order to utilize this material, more eco-friendly green dissolution methods are also required. As a green solvent, ionic liquids (ILs) have been attracted too much interest in processing of lignocellulosic biopolymers, but the practical effect of lignin on this process was not clear. In this due, production of lignocellulosic bio-composite films from bleached (lignin-free) and unbleached (lignin-containing) soda pulps was studied. First, fibers were dissolved in 1-Buthyl 3-Methyl Imidazolium Chloride (BMIMCL) at 85-95 C. Following fabrication and preparation of the lignocellulosic films, certain
Cationic starch has been widely used with various mineral nanoparticles such as nanosilica, in wet-end of papermaking. This study was aimed to study the effect of cationic starch with different degrees of substitution (DS: 0.018 and 0.045) in nanoparticle containing system with nanosilica, in recycled OCC pulp. In this respect, initially, to study the shape and dimensions of nanosilica sol particles, atomic force microscopy (AFM) and transmission electron microscopy (TEM) was used; thereby the average size of nanosilica sols were measured less than 50 nm. Moreover, in order to study the papermaking process parameters, the results revealed that high DS cationic starch (0.045) resulted more effective interactions with silica nanoparticles, so
Improving the processing and the recycled paper properties is one of permanent concern of papermaking. In this research, the effect of nanochitosan addition on the process and product quality made of writing and printing recycled fiber was investigated. Being nano size and so its capability in access to the space between pulp suspension components and also its probable ability to make electrostatic and hydrogen bonds are the characteristics of nanochitosan. For this purpose, the chitosan nanoparticles were prepared and their size and shape was confirmed with AFM and FE-SEM. Also, the change in FTIR spectrum after conversion of chitosan to nanochitosan was considered and omitting the–NH 2 in chitosan and creation of–CONH groups in nanoch
Production of test liner and fluting paper from old corrugated containers is one of the most common paper recycling processes in Iran. This type of papers are among the high basis weight papers and also contain significant fine fibrous and non-fibrous materials. Hence, the drainage and in addition, the retention of fine materials, are the obstacles for the paper mills. In these cases, usually application of drainage/retention aids, such as nanoparticle systems can be of good help. In this respect, colloidal silica and bentonite are the two most commonly used nanoparticles with polyelectrolytes in papermaking wet-end. Therefore, in this research, the effect of bentonite and silica sol nano-particles on the performance of cationic starch was
Chitosan is a widely used biopolymer with very attractive properties. However, to compensate for the deficiencies in the application of this bio-macromolecule, many studies have been performed on the preparation of chitosan blends with various polymers, such as cellulose, which is abundant and unique with a tough bio-structure. Because of the different dissolution conditions of chitosan and cellulose, an acceptable industrial and environmentally friendly process to prepare a monotonous cellulose-chitosan composite film has not been achieved yet. Therefore, as an alternative approach, nanochitosan (Nano-CS) particles were synthesized and blended with a cellulose matrix, which was dissolved using ionic liquid. Atomic force micr
To compensate for some inferior properties of recycled papers, application of processing chemical aids such as chitosan can be quite effective in the wet end section of papermaking. In this study, the performance of chitosan biopolymer, individually or associated with nanobentonite was investigated as wet end additive on recycling process of white cuttings. For this purpose, the performance of this biopolymer at 0.5, 1, 1.5 and 2%(based on oven-dried pulp) were compared in a single polymer system or with nanobentonite. The results revealed that dosing different amounts of chitosan resulted in increasing tensile, tear and burst indices. Moreover, improvement in first pass retention (5 and 10% in single and nanoparticle system, respectively)