Recycled Cellulose Research Articles

Migration of Phthalates from Cellulose Packaging into Food Simulant: Assessment of Different Levels of Contaminants

AbstractSince paper recycling operates with market‐collected paper scrap, this may lead to undesirable chemicals migrating from the wastepaper into the recycled material. Therefore, this study is based on the assessment of several additives inadvertently included in cellulose packaging that may migrate to foodstuff, considering that toxicological effects of some of these additives may persist in recycled cellulose fibers used to produce new food packaging. The purpose of this study is to determine migration of dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), bis(2‐ethylhexyl) phthalate (DEHP) and 2,6‐diisopropylnaphthalene (DIPN) into fatty food simulant (n‐heptane) by means of gas chromatography with flame ionization detector (GC‐FID). For this purpose, commercial samples of cellulose food packages are contaminated with different concentrations of these additives, and migration into the food simulant is evaluated after the samples remain in contact with the food simulant for a prolonged time at maximum temperatures of 40 °C. The results of the assessment show that an amount ranging from 0.1–0.3% of phthalates and DIPN migrate from the fortified package into the fatty food simulant. The maximum levels of migration of these additives into the recycled cellulose packaging in order to comply with the specific migration limits for contact with foodstuff have been estimated.

Tests of Fiber Cement Materials Containing Recycled Cellulose Fibers.

This paper presents the results of investigations into the effect of the use of recycled waste paper cellulose fibers on the properties of fiber cement boards subjected to contamination by moisture. Four series of fiber cement boards were tested. A reference fiber cement board manufactured without the use of recycled cellulose fibers constituted as one of the series. The other three series consisted of boards differing in their recycled cellulose fiber content-ranging from 10% to 50% of the total cellulose fiber content. Specimens of the fiber cement boards were subjected to contamination by moisture by storing them in water for 1–96 h. Subsequently, their basic physical and mechanical parameters, i.e., mass moisture content, absorbability, and modulus of rupture (MOR), were tested. Then, the specimens were investigated by means of acoustic emission during three-point bending. Artificial neural networks were employed to analyze the acoustic emission test results. The tests clearly showed the amount of recycled waste paper cellulose fibers and the length of storage in water to have an adverse effect on the boards, contributing to their degradation. This was reflected in the decrease of the acoustic emission (AE) events count recognized by the artificial neural networks, accompanying the rupture of fibers during the three-point bending of the specimens. In order to gain a more detailed insight into the changes taking place in the structure of the tested fiber cement boards, optical examinations were carried out by means of a scanning electron microscope. Interesting findings crucial for building practice were noted.

Modified recycled paper-based adsorbent for nickel removal

The outcome from the industrialization and urbanization promotes the environmental problems especially related to the release of heavy metals. The adsorption method is a promising technique among all the available approaches in heavy metal removal treatment due to its high efficiency, low cost, and simplicity in design and operation. A good selection of solid sorbent becomes one of the greatest problems in adsorption technique. In this present work, we developed recycled paper-based cellulose adsorbent grafted with acrylonitrile in the presence of ceric ammonium nitrate as the initiator. The modified adsorbent was used to adsorb Ni(II) from the aqueous solution. The adsorption process was conducted at different operational conditions by varying the pH of the solution, initial concentration of the Ni(II), and the contact time for the adsorption to reach equilibrium and obtained the highest adsorption capacity. The result demonstrated that the grafted recycled paper-based cellulose adsorbent had improved the adsorption capacity of Ni(II) ions. The most propitious condition obtained was at pH 5 after 1 h, with an initial concentration of 160 mg/L of Ni(II) ions; the removal reached 317.5 mg/g (79.3% removal). The surface studies of the adsorbent before and after Ni(II) ions adsorption was analyzed by using the scanning electron microscopy (SEM). The adsorption equilibrium data of Ni(II) ions was best described by the Freundlich and Pseudo-second-order model. Conclusively, the prepared grafted recycled paper-based cellulose adsorbent proved to be competitive and a promising adsorbent for the removal of Ni(II) ion from aqueous solution, as well as in wastewater treatment application.

Photothermal-responsive tungsten bronze/recycled cellulose triacetate porous fiber membranes for efficient light-driven interfacial water evaporation

Solar-driven steam generation is a common strategy for clean water production and wastewater treatment. Tungsten-oxide-based composites have lately gained significant attention due to their capability of absorbing near-infrared (NIR) light and transforming it into heat for evaporating water. The strong surface plasma resonances and intervalence charge transfer of these composites result in high photoabsorption in a wide NIR spectrum. Here, we fabricate combined rubidium tungsten bronze and recycled triacetate cellulose (RbxWO3/rTAC) porous fiber membranes without any supporting components, via solution electrospinning. The as-prepared RbxWO3/rTAC porous fiber membranes float on the water surface because of their low weight and hydrophobicity. RbxWO3 (0, 5, 10, 15, and 20 wt%) was incorporated into a recycled triacetate cellulose (rTAC) matrix, and its efficiency for light-driven water evaporation was calculated. The rTAC polymer, significantly contributes toward its desirable wetting properties and its porous structure, which are favorable for solar steam generation. The results showed that the evaporation efficiency of RbxWO3/rTAC fiber membranes with an optimized 15 wt% of RbxWO3 nanorods reached 90.4 ± 2.1%, which is considerably greater than that of pure rTAC fiber membranes and of pure water. A great potential has also been proved by simulating solar exposure, with a water conversion efficiency of approximately 73.6%. Thus, RbxWO3/rTAC photothermal fiber membranes can find applications in water purification, desalination, and steam power generation.

Photocatalytic, antibacterial, and deodorization activity of recycled triacetate cellulose nanocomposites

In this study, industrial waste triacetate cellulose (TAC) film was used for electrospinning by combining the concepts of mixed solvents system and steam induced phase separation to prepare porous fiber membranes. Recycled TAC (rTAC) was used as the host matrix for the preparation of nanocomposites with titanium dioxide (TiO2)/silver vanadate (Ag3VO4)/graphene (Gp) photocatalytic nanoparticles, and 3-Aminopropyl-trimethoxysilane (APTMS) was used as a coupling agent. The photocatalytic performance of TiO2/Ag3VO4/Gp regarding photo degradations of Rhodamine B (RhB), methylene orange (MO) and methylene blue (MB) dyes were examined. The photocatalytic performance of TiO2/Ag3VO4/GP/APTMS/rTAC nanocomposites towards photodegradation of MB, the acetate deodorization ability and antimicrobial activity were studied. The porous fibers and photocatalytic nanoparticles were designed to absorb and decompose organic acetate, respectively. The result showed that the as prepared TiO2/Ag3VO4/Gp exhibited excellent photocatalytic activity towards photodegradation of RhB, MO, and MB. TiO2/Ag3VO4/Gp displayed high rate of MB dye photodegradation about 5 and 115 times faster than pure Ag3VO4 and TiO2, respectively. The prepared TiO2/Ag3VO4/GP/APTMS/rTAC nanocomposites exhibited a photocatalytic degradation efficiency of 99% for MB, strong antibacterial activity, and 100% deodorization. TiO2/Ag3VO4/GP/APTMS/rTAC nanocomposite presented photocatalytic performance about 1.2 times faster than that of TiO2/Ag3VO4/Gp photocatalytic nanoparticles. Thus, this multifunctional nanocomposite is promising for the photocatalytic photodegradation of dyes, as an antimicrobial and deodorizing substance.

Recycled Cellulose Aerogels from Paper Waste for a Heat Insulation Design of Canteen Bottles

Exercising in a tropical climate with constant high temperatures and high humidity increases the risk of heatstroke for active people who frequently train outdoors. For these active persons, a cooling source of water nearby can be essential, and this is usually carried in canteen bottles. However, commercially available water canteen bottles have limited thermal insulation capability to keep the liquid content cooled for the required period. This work proposed an engineering solution to enhance the heat insulation performance of water canteen bottles, using recycled cellulose aerogels made from paper waste for the first time as an insulating layer. Recycled cellulose aerogels wrapped around the water canteen bottle provides excellent thermal insulation performance, while not adding significant weight to the bottle. The temperature of the ice slurry in the canteen bottle was measured periodically over four hours with a mercury thermometer. The effects of the static and dynamic conditions on the temperature rate were also quantified. A 1.5 cm thickness of 1.0 wt.% recycled cellulose aerogel wrapped around the canteen bottle can provide an excellent thermal insulation performance with the lowest rise in temperature, achieving a low final temperature of the ice slurry content of 3.5 °C after 4 h. This result is much better than that provided by available commercial bottles under the same conditions.

Losses of poly- and perfluoroalkyl substances to syringe filter materials

Syringe filters are used to separate solids from liquids prior to analysis of poly- and perfluoroalkyl substances (PFASs). This is a critical step in sample preparation, as losses of PFASs to the filter material can be significant and lead to underestimation. This study evaluated losses of 21 PFASs in three different matrices (methanol, MilliQ water, and water containing 10 mg L−1 dissolved organic carbon (DOC)) to six different types of syringe filter (0.45 and 0.22 μm). Regarding sample matrix, the lowest average ∑21PFAS losses were observed in methanol (13%), followed by DOC water (19%) and MilliQ water (26%). Regarding syringe filter material, the lowest average losses of ∑21PFAS in DOC water and MilliQ water were observed for a recycled cellulose filter (average losses 16% and 21%, respectively), while a polypropylene filter had the lowest ∑21PFAS losses in methanol (9%). A smaller polyethersulfone (PES) filter (0.22 μm, 17 mm Ø) showed significantly (p < 0.05) lower ∑21PFAS losses in DOC water (on average 7.3%) than a larger PES filter (0.45 μm, 37 mm Ø) (23%). In DOC water, losses to the filter increased by 3.8%, 5.1%, and 8.4% per CF2-moiety for C3-C11 perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFSAs), and fluorotelomer sulfonic acids (FTSAs), respectively. Comparing different functional groups of PFASs, losses increased as follows: PFCAs < PFSAs < FTSAs < perfluorooctanesulfonamides (FOSAs). Thus, care is needed when including filtration in PFAS analysis, since losses can be significant (up to 100%) depending on the type of syringe filter, target PFAS, and matrix.

Recycling of cellulose from vegetable fiber waste for sustainable industrial applications

Recently two significant topics that became important for textile industry namely ‘providing sustainability by reusing of textile wastes’ and ‘developing high-valued new textile raw materials. Cellulose, which is a fascinating polymer, has been used for years as a raw material to obtain various products such as papers, fibers and films. In this study, it is aimed to provide sustainability with recycling of cellulose from waste jute fibers, considering the amount of waste jute weft yarns released in the production process of machine carpets. For this purpose, pre-cleaning of waste fibers was carried out at first, and then extraction of cellulose was accomplished, and finally characterization of recycled cellulose was performed. Organic acid extraction method was effective for isolation of cellulose from waste fibers with 43.65% yield performance. Microscopic and experimental analyses confirmed that non-cellulosic part of waste fibers were removed successfully and recycled cellulose has similar structure with control cellulose. Our results suggest that, waste vegetable fibers can be used as a potential source for cellulose. Recycled cellulose can be used in the production of paper, composites, regenerated cellulose fibers and other industrial applications.

UTILIZATION OF RECYCLED POLYPROPYLENE, CELLULOSE AND NEWSPRINT FIBRES FOR PRODUCTION OF GREEN COMPOSITES

This work investigates the feasibility of using the recycled polypropylene (rPP), cellulose (CF) and newsprint (NP) fibres in polyolefin reinforced composites. Recycled PP filled with 40 wt.% of cellulose (rPP/CF) or newsprint (rPP/NP), with the addition of impact modifier (IM) and compatibilizing agent (CA), have been prepared with extrusion melting and injection moulding. Melting and crystallization behaviour of plain matrix and composites were measured by differential scanning calorimetry (DSC). Morphological and mechanical properties were also studied using scanning electron microscope (SEM) and tensile testing, respectively. Thermal stability of composites was similar to neat rPP for both types of the filler used. Though, the crystallinity was progressively decreased with the addition of CF or NP. The DSC further revealed an occurrence of the two distinct melting transitions, meaning that the examined materials were not based on pure polypropylene (PP), but are rather blends of high-density polyethylene (HDPE) and PP, what has been confirmed also by the Fourier transform infrared spectroscopy (FTIR). The largest single source of contaminations in recycled PP comes from HDPE since both polymers are identified by a similar density and can be accidentally mixed during the conventional physical separation process. Composites reinforced with CF have shown better mechanical performances than those based on reclaimed NP fibres, what can be attributed to the initial fibre quality. Tensile strength of the composites filled with CF and NP fibres was 36 MPa and 29 MPa, respectively, in disparity to 23 MPa measured for neat rPP. The fibre addition further resulted in substantial increase in Young modulus of the composites. The addition of CF and NP fibres lead to an improved modulus of elasticity by 16 and 47%, respectively. Waste paper in the form of recovered cellulose or reclaimed newsprint fibre can thus meet all the technical requirements to become an alternative to inorganic fillers in thermoplastic composites.

Influence of cellulose fibers on structure and properties of fiber reinforced foam concrete

One of the promising means of foamed concrete quality improvement is micro-reinforcement by adding synthetic and mineral fibers to the base mix. This research is the first to investigate peculiarities of using recycled cellulose fiber extracted from waste paper for obtaining fiber reinforced foam concrete. The paper presents results of experimental research on the influence of cellulose fibers on structure and properties of fiber reinforced foam concrete by using methods of chemical analysis and scanning electron microscopy. The research determines peculiarities of new formations appearance and densification of binder hydration products in the contact zone between fiber and cement matrix, which boost mechanical strength of fiber reinforced foam concrete. Physico-mechanical properties of fiber reinforced foam concrete were defined depending on the amount of recycled cellulose fiber added to the base mix. It was found that the use of recycled cellulose fibers allows obtaining structural thermal insulating fiber reinforced foam concretes of non-autoclaved hardening of brand D600 with regard to mean density with the following improved properties: compressive strength increased by 35% compared to basic samples, higher stability of foamed concrete mix and decreased shrinkage deformation.

Recycled cellulose from Tetra Pak packaging as reinforcement of polyester based composites

Addressing the environmental problems caused by waste generated by Tetra Pak packaging, in this work, polyester based composites with 80% of polyester resin and 20% of silica sand were elaborated; where the silica sand was partially replaced by recycled cellulose from waste Tetra Pak containers at concentrations of 1, 2, 4 and 6% by weight. Both recycled cellulose and composite specimens were subjected to ionizing radiation process by using gamma rays. The results show improvements on the mechanical properties (compressive and flexural strength as well as modulus of elasticity) of the composites when they are irradiated at 100 and 200 kGy. Such improvements can be related with the structural modifications caused by gamma irradiation on the cellulose fibers, including changes in the morphology and the crystallinity; which were analyzed through to SEM, IR and XRD techniques.

Ionic Liquid Approach Toward Manufacture and Full Recycling of All‐Cellulose Composites

AbstractAll‐cellulose composites (ACCs) are prepared from high‐strength rayon fibers and cellulose pulp. The procedure comprises the use of a pulp cellulose solution in the ionic liquid (IL) 1‐ethyl‐3‐methyl imidazolium acetate ([EMIM][OAc]) as a precursor for the matrix component. High‐strength rayon fibers/fabrics are embedded in this solution of cellulose in the IL followed by removal of the IL. Different concentrations of cellulose in the IL are investigated and the mechanical properties of the final ACCs are determined via tensile, bending, and impact testing. ACCs prepared in this study show mechanical properties comparable to thermoplastic glass fiber‐reinforced plastics. Apart from being bio‐based, they possess several advantages such as biodegradability and full recyclability. The recycling of ACCs is successfully demonstrated in several cycles by using the recycled cellulose for subsequent matrix preparation.

Techno-economic analysis of waste paper energy utilization

ABSTRACTThe existing waste paper recycling technologies are based on partial incorporation of recycled cellulose fibers into “new” paper products. The main usage is in low-grade products, such as paperboards or wrapping papers. However, due to electronization of mass media in combination with increasing quantities of leaflets and continuous downward pressures on paper production costs, the waste paper currently used in the recycling scheme is of lower quality than paper used decades ago. It contains much more fillers, adhesives, dyes, polishers, and similar additives that are problematic for conventional paper recycling technologies. A sharp growth of this trend encourages conceptual reengineering of the existing technological processes in waste paper management. A techno-economic analysis of energy utilization by means combustion, anaerobic fermentation (also accelerated by steam-explosion), and pyrolysis was carried out in a pilot scale. The results have revealed that if the current trend continues, it might be reasonable to divert waste paper from returning back into production (recycling) and to prefer its commercial pyrolysis.

Isolation of Nanocrystalline Cellulose: A Technological Route for Valorizing Recycled Tetra Pak Aseptic Multilayered Food Packaging Wastes

Cellulose fibres were extracted from recycled Tetra Pak food packaging which can be a source of low cost biomass using a simple process. According to the FT-IR and XRD results, alkaline purification and bleaching have removed 99 % of the lignin that remained in the recycled cellulose fibres (up to 10 %). TEM analysis showed that depending on cellulose purity and reaction time, the average particle lengths of nanocrystalline cellulose (NCC) successfully isolated from the recycled material using acid hydrolysis ranged from 127 ± 42 to 258 ± 54 nm with average widths varying between 11.4 ± 2.8 and 14 ± 4.1 nm. Extending the reaction time to 180 min led to short rod-like particles displaying crystallinity comparable to those of the reference NCC isolated from commercial microcrystalline cellulose. A decline in the NCC thermal stability was noticed following the extraction process, NCA isolated from unpurified starting fibres showed a slightly higher stability with Tmax = 204 °C. Overall, a length to diameter aspect ratio >10 was obtained for all NCC particles, indifferently of the purity of the starting materials.

Effect of prolonged water absorption on mechanical properties in cellulose fiber reinforced vinyl‐ester composites

With the increasing of worldwide societal awareness about environmental impact, sustainability, and renewable energy sources, the polymer natural fiber composites recently have attracted the attention of researchers due to the fact that they are recyclable and biodegradable. This study conducted a new infiltration method that involved very thin sheets of recycled cellulose fibers (RCF) being fully soaked in vinyl‐ester resin for the development of natural fiber reinforced polymer composites. The effect of prolonged water absorption on the mechanical behavior of cellulose fiber (0–50 wt%) reinforced vinyl‐ester composites was investigated. The elastic modulus of these composites was measured and the data were validated with various mathematical models. The modeling results revealed that the experimental data matched the prediction data obtained by the Cox–Krenchel model. Prolonged exposure of these composites to water absorption caused a reduction in elastic modulus, strength, and toughness. POLYM. ENG. SCI., 55:2685–2697, 2015. © 2015 Society of Plastics Engineers

Possibilities of Using Natural Fibres for Production of Particular Insulation for Use in Civil Engineering

The paper deals with the development options of particular insulation based on a blend of recycled cellulose fibers and natural (mainly) bast fibers. The paper presents the results of research work in the field of addiction thermal insulation, acoustic and mechanical properties of experimentally produced insulators on density..Keywords: Natural fibers, thermal conductivity, insulation materials, straw, fibreboard, cellulose fibers

Advanced fabrication and oil absorption properties of super-hydrophobic recycled cellulose aerogels

A facile and cost-effective synthesis method of biocompatible cellulose aerogels using recycled cellulose fibers of paper waste and Kymene crosslinker is successfully developed for the first time. After coated with methyltrimethoxysilane (MTMS) via chemical vapor deposition, the recycled cellulose aerogels yields very stable super-hydrophobicity for over five months and excellent oil absorption capacities of up to 95gg−1 with the 0.25wt.% cellulose aerogel. Effects of different cellulose fiber concentrations, different ratios of the cellulose and Kymene cross-linker composition, ambient temperatures and pH values of the environment on the oil absorption behavior of the cellulose aerogels are also quantified comprehensively. The experimental results show the cellulose aerogels yield the maximum absorption capacity at 50°C. Compared to the pseudo first-order model, the pseudo second-order model is more validated for the oil absorption kinetics study. The recycled cellulose aerogels are promising for replacing earth-unfriendly polymer-based oil sorbents due to their high oil absorption capacities.

Production of recycled cellulose fibers from waste paper via ultrasonic wave processing

ABSTRACTRecycling waste paper can be considered as a means to displace the use of natural cellulose fibers applied in building materials, because it is composed mostly of cellulose. The water absorption and special surface area of cellulose fibers are the key properties for their use in building materials. The objective of this article was to study the production of recycled cellulose fibers from waste paper using ultrasonic wave processing. The physical and chemical properties of recycled cellulose fibers, such as water absorption, specific surface area and pore characteristics, etc., were investigated with various testing methods. The results indicated that the ultrasonic cavitation effect was feasible for the preparation of the secondary fibers. When the ultrasonic treatment time lasted for 10 min, the water absorptions of both newsprint fibers and kraft fibers increased significantly and reached the highest values of 12.5 g/g and 11.2 g/g, respectively, which were nearly two times than that of fibers without ultrasonic treatment. With a pretreatment of 20 min, the average length and fineness of recycled cellulose fibers decreased by 4% and 25%, respectively, and the length‐diameter ratio of the recycled cellulose fibers was 1.28 times than that of the untreated fibers, which greatly increased the special surface area of the recycled cellulose fibers. This work also determined that NaOH was useful to improve the physical properties of the recycled cellulose fibers. Because the recycled cellulose fibers after processing, fulfilled several technical indexes, they can be considered as a filling material for used in cement‐based materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41962.

Waste of Molded Pulp Industry. Filler Panel Production for Construction

In the production process for producing recycled pulp cellulose, there are waste generated by the raw material entering the system. This residue is separated from the pulp by physical methods, and is mainly composed of plastics, paper, laminated papers and other materials in smaller proportions.In order to recycle this waste, in this paper we analyze the viability of use in the production of insulated panels.With the untreated residue extracted from the plant, panels of 30cm side and thickness of approximately 6cm were made. On these panels, parameters such as density and compression strength were evaluated for the study of the homogeneity of the material obtained.

Green bio-based aerogels prepared from recycled cellulose fiber suspensions

The flammability of green aerogels prepared using recycled cellulose fibres was improved by adding clay and ammonium polyphosphate.