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This study analyzed the effect that pulp fibers have on the surface softness component of hygiene paper. The surface softness component has more of an influence on the evaluation of subjective softness results than the bulk softness component. Using the surface softness measurement technique, this study aimed to evaluate the effect that fibers have on the softness of hygiene paper substrate via objective numerical values to measure the surface softness component of hand sheets composed of various pulp species. The results indicate that coarseness effects had the largest effect on softness among the various fiber characteristics, such as average fiber length, width and coarseness. As fiber coarseness increased, a rough surface formed, which resulted in an increase in the mean deviation from the average friction (MMD). Nonwood fibers had long fiber length and low coarseness, which enables the production of hygiene paper with high strength and softness. This study hopefully could lead to the development of various process technologies that may improve the softness of hygiene paper products.

The inorganic core-shell pigment CaCO 3 {\mathrm{CaCO}_{3}} @ SiO 2 {\mathrm{SiO}_{2}} was synthesized using a sol-gel method, and the pigment was applied as a surface coating on inkjet paper to study the influence of inorganic core-shell pigments on the dynamic permeability, surface properties, optical properties and inkjet-printing performance of coated paper. CaCO 3 {\mathrm{CaCO}_{3}} @ SiO 2 {\mathrm{SiO}_{2}} prepared using carboxymethyl cellulose (CMC) had better coverage than that prepared using polystyrene sodium sulfate (PSS) dispersant. The CMC-prepared CaCO 3 {\mathrm{CaCO}_{3}} @ SiO 2 {\mathrm{SiO}_{2}} -a had improved dispersibility, and the solids content of the coating reached 35 %. Inorganic core-shell pigments improve the surface and optical properties of the coated paper, making them similar to those of a reference calcium carbonate-coated paper. The smoothness and gloss improved by 60.8 % and 78.4 %, respectively, compared with those of silica-coated paper. The inkjet solid density and dot definition increased by 28.8 % and 4.1 %, respectively, compared with those of the calcium carbonate-coated paper. Preparing inorganic core-shell pigment CaCO 3 {\mathrm{CaCO}_{3}} @ SiO 2 {\mathrm{SiO}_{2}} is an effective method to fabricate inkjet printing coatings with advantageous microstructures for ink absorption.

AIMS: The utilization of micro‐organisms in pulp and paper industries has proved biobleaching technology as an environmentally friendly alternative to the conventional approach. In this paper, the effect of actinobacterial fermentation broth on pulp biobleaching has been investigated. METHODS AND RESULTS: Actinobacterial colonies were isolated from lignocellulose‐rich soil samples and screened for xylanase production and bleaching activity. The most efficient isolate in bleaching activity showed 100% similarity to Streptomyces rutgersensis. Pulp treatment with 5‐day fermentation broth of this strain showed up to 7% increase in brightness (30°C for 6 h, pH (5–7)) compared to untreated (control) pulp. Also, after 60 min biotreatment, significant reduction (12·5%) in consumption of bleaching chemicals was achieved to obtain final brightness of 55%. CONCLUSION: Actinobacterial fermentation broth can be considered as a rich source of effective biobleaching agents which may be considered as environmental friendly and cost‐effective technique in comparison with traditional method. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings showed ability of S. rutgersensis UTMC 2445 in bleaching chemomechanical paper pulp. Also, two strains of Saccharothrix, a rare actinobacterium, with biobleaching activity were introduced. In the proposed method, there is no need to use purified enzymes, and biobleaching process can be done using the fermentation broth.

The aim of this study was to clarify the anatomical characteristics and predicted paper quality of Eucalyptus urophylla, E. grandis, and E. pellita planted in North Sumatra, Indonesia. In addition, potential hybridization among the three species was explored. The anatomical characteristics of the fiber (length, diameter, and wall thickness), vessels (element length, diameter, and frequency), the proportions of cell types, and the derived wood properties related to pulp and paper quality were examined for these three 9-year-old Eucalyptus species. The obtained results showed that vessel element length as well as fiber and ray parenchyma proportions significantly differed among the three species. Higher fiber and lower ray parenchyma proportions were observed in E. grandis, indicating that this species would be the best mother tree in a hybridization program for pulp and paper utilization, with the other two species complementary for refining the paper quality through this program. In terms of derived wood properties, the three species were considered to be promising raw material for the pulp and paper industry compared to other species that are broadly used as raw material for high-grade pulp and paper-based products.

The main objective of this study is the evaluation of RPPW anaerobic digestion feasibility at laboratory scale under Mesophilic condition. The experiment is conducted using a two-stage biofilm digester of 5 L capacity with mobile support material. Anaerobic treatment of wastewater from recycled pulp and paper industry in Morocco was tested using a laboratory-scale anaerobic biofilm digester that operated under mesophilic conditions over a 70-day. Chemical oxygen demand (COD) efficiency, volatile and total solid (VS, TS) elimination of the substrate during the process were: 78%, 52% and 48% respectively. The system was stable throughout its operating cycle with an optimum pH (7.24), alkalinity (1750 mg CaCO3/L) and a volatile fatty acid value (760 mg/L). The experimental daily biogas production measured reaches a value of 5 L/day with a composition of 71% methane, 27.6% carbon dioxide, 0.2 oxygen and 7713 ppm of the H2S. The study results show that the anaerobic biofilm reactor is a suitable technique for recycled pulp and paper wastewater (RPPW) treatment. The reactor shows high performances in terms of process stability, removal efficiency (> 70%) and biogas production. Anaerobic digestion is an efficient waste treatment technology that uses natural anaerobic decomposition to reduce the volume of waste while producing biogas. However, research is needed to strengthen microbial metabolism, biochemistry and the functioning of the rector to improve biogas production. The RPPW AD experiment with biofilm digester technology was stable throughout the operation period. The digester knows an overloaded in the last phase of the experiment which leads to an inhibition of biogas production.

In this study, it is aimed to investigate the joining of filter paper, which we classify as oil, fuel and air filter by four different methods. It has been determined whether it meets the post-merger requirements or not. The oil, air and fuel filter papers are pleated using pleats, ultrasonic, metal clips, polyamide-based hot melt and heat after being pleated (folded) to form media. Post-merger macro studies were performed after combination. Media was transformed into final filter product than buble test, air permeability and pore size test were applied. In terms of bonding quality, respectively it can be said that the metal clips, hot glue, ultrasonic welding and heat bonding methods should be, but in considering both quality bonding and to make saving, then metal clips, ultrasonic welding, hot glue, and heat methods should be followed.

The advancement in plastic and plastic based products in last two decades has imposed a serious threat to the environment. This has led to an increase in the demand for sustainable and biobased products. Paper and paper products are good alternatives to their plastic counterparts. A key element of paper industry is the raw material (wood, bamboo and nonwood agricultural residues such as bagasse, straws etc.) from which pulp is produced. The pulp is then utilized for production of paper. There are many pulping processes to prepare pulp of various qualities. For fine grade pulp, chemical pulping is used. The chemical pulp is produced by soda, kraft and sulphite pulping processes. However, for newsprint grade pulp, stone ground wood (SW), thermomechanical (TMP), chemi-thermomechanical (CTMP), chemi-mechanical (CMP) or refiner mechanical (RMP) corresponding pulping processes are employed. The method of pulp preparation (pulping process) consumes large amount of energy and chemicals. A new pulping process with electron irradiation using biowaste (bagasse) as a raw material is discussed in this work. Bagasse pulping process is found to reduce about 50% of energy consumption during pulping process. The process is referred to as ‘ECTMP’ (Energy Efficient Chemi-Thermo Mechanical Pulping). The paper produced from aforesaid method also reflected no loss of strength properties with respect of TMP reference pulps. Henceforth, preliminary calculation based on experimental results shows that the proposed bagasse ECTMP process explored the scope of energy savings of the order of 50%.

Coatings based on pigment and polymer binders are applied on paper surfaces to improve their surface, optical, and printing properties. Besides the coating composition, the structure and properties of the coated papers are influenced by the coating layer consolidation upon drying. In this study, the influence of drying conditions on the structure and properties of coating layers based on natural pigments (clay) and polymer binders (butadiene acrylonitrile latex) has been analyzed. Using a laboratory rod Mayer device, the coatings were applied as thin layer (about 15&ndash, 16 g/m2) on the paper surface and samples of coated paper were dried at 20 and 105 &deg, C temperatures. The optical, structural, and water absorption properties of the coating layer were evaluated by the measurement of gloss, opacity, void fraction, light scattering, and contact angle. The obtained results highlighted that both the drying temperature and latex content in the coating color have a synergic effect on the coated paper quality.

Highlights • Pulp and paper mills generate huge amount of wastewater. • Physicochemical processes have several limitations to treat wastewater. • Integrated microbial based technology improves the quality of wastewater. • Eco-friendly MBBR process creates opportunity for reuse of treated wastewater., From the beginning of the paper-making process, the pulp and paper industry has utilized a large amount of water and generated a vast amount of highly polluted wastewater. The paper industry faces global pressure to reduce water use and lower environmental pollution. However, traditional physicochemical methods of wastewater treatment need high energy input, and their ecological impact is questionable. Due to the zero discharged policy, the industries urgently require novel eco-friendly, sustainable, and efficient treatment techniques. Microbial technology is the most recommended option to treat wastewater and support sustainable growth. The present article describes the overview of traditional and novel methods, including membrane bioreactor (MBR) and moving-bed biofilm reactor (MBBR) technology's with their current state and their limits for treating pulp and paper wastewater. It is expected to integrate the novel methods with advanced hybrid technology to fulfill wastewater treatment criteria and prospects. Furthermore, coupling MBR and MBBR technology make energy and water recovery possible, and recycling wastewater will be economically and environmentally feasible., Graphical abstract Image, graphical abstract

This study introduces a novel geotechnical composite material comprising two types of fill material sourced from the paper industry-deinking paper sludge ash (DPSA) and deinking paper sludge (DPS). Five composites with different DPSA and DPS contents were investigated. Two composites were selected for further analyses. The technology and procedure for composite installation were implemented in field tests. The composites with 80% and 70% DPSA exhibited the elasticity required to withstand minor landslide slip deformations, in addition to achieving sufficiently high values of uniaxial compressive strength. The composites had a low maximum dry density value, which led to fewer settlements in the entire support structure. The enhanced shear characteristics can enable the construction of a thinner retaining wall. The delay between preparation and installation of the composites was further investigated. The field tests confirmed that the composites with 80% and 70% DPSA can be installed on the construction site 4 h and even 24 h after mixing. In 2018, a retaining wall structure with 70% DPSA and 30% DPS was successfully implemented near a railway line using conventional technology as followed-up research to the herein presented study. Results have been derived from work performed in the scope of the H2020 Paperchain project in which novel circular economy models centered on the valorization of the waste streams generated by the pulp and paper industry as secondary raw material for several resource-intensive sectors, including the construction sector, have been developed. Environmental benefits are savings in natural raw materials, reduction of landfill disposal as well as CO2 emission reduction. Nasl. z nasl. zaslona. Opis vira z dne 16. 11. 2021. Št. članka 22363. Bibliografija: str. 12-13. Abstract.

Objectives: This study analyses the implementation of an environmental management system based on the ISO 14001 standard, which can support corporate sustainability performance in the pulp and paper manufacturing industry in Indonesia. This study discusses the results of previous researchers related to the implementation of environmental management systems in supporting the achievement of corporate sustainability performance. Research Methodology: The research method used is a case study approach in five organizations from three pulp and paper manufacturing companies in Indonesia that have implemented environmental management systems. Collecting data through a questionnaire completed by representatives from organizations across the companies studied. Findings: Management commitment and implementation of internal audits that focus on environmental management and activities are the main factors contributing to the achievement of environmental performance. Meanwhile, the achievement of environmental performance is influence by employees' increased competence in the environmental field, programs to reduce energy consumption, and hazardous and toxic waste. Practical implications: The implementation of an environmental management system supported by an increase in environmental performance can improve the company's reputation, process efficiency and compliance with environmental regulations and requirements, that three things contribute to company performance, especially in the pulp and paper manufacturing industry. Novelty: This research contributes to the concept of a strong relationship between the implementation of environmental management systems and environmental performance in supporting the achievement of corporate sustainability performance, especially in the pulp and paper manufacturing industry in Indonesia.

Tissue paper production frequently combines two main types of raw materials: cellulose fibers from renewable sources and polymer-based additives. The development of premium products with improved properties and functionalities depends on the optimization of both. This work focused on the combination of innovative experimental and computational strategies to optimize furnish. The main goal was to improve the functional properties of the most suitable raw materials for tissue materials and develop new differentiating products with innovative features. The experimental plan included as inputs different fiber mixtures, micro/nano fibrillated cellulose, and biopolymer additives, and enzymatic and mechanical process operations. We present an innovative tissue paper simulator, the SimTissue, that we have developed, to establish the correlations between the tissue paper process inputs and the end-use paper properties. Case studies with industrial interest are presented in which the tissue simulator was used to design tissue paper materials with different fiber mixtures, fiber modification treatments, micro/nano fibrillated cellulose, and biopolymer formulations, and to estimate tissue softness, strength, and absorption properties. The SimTissue was able to predict and optimize a broader range of formulations containing micro/nanocellulose fibers, biopolymer additives, and treated-fiber mixtures, saving laboratory and industrial resources.

Pulping trials were carried out using MEA and the soda process comparing their pulping potentials. The operating conditions such as the concentration of the cooking liquor (50%, 75%, 100%) for MEA and (10%, 15%, 20%) for NaOH, the maximum cooking temperature (150oC, 160oC, 170oC) and cooking time (60, 90, 120minutes) for both processes were investigated systematically to establish optimal pulping conditions. The agro-biomass used in this investigation is Sugarcane Bagasse viewed as alternative raw material for pulp and paper production. The lignin content of Bagasse (19.5%) was low; indicating that Bagasse should be easier to pulp. The optimum cooking conditions (independent variables) for MEA pulping were 75% MEA concentration, 150oC cooking temperature and 90 minutes cooking time. Excel 2013 was used to analyze the effect of independent variables on yield of bagasse pulp and properties of furnished paper from MEA process in comparison with the Soda process which include tear index, tensile index, burst index and folding endurance with errors less than 15% in all cases. The Kappa number range (12.7-16.9), viscosity (270-870 ml/g) and brightness (62.1-93.2%) of bagasse pulp are appropriate for high-brightness printing and writing papers. The physical properties of furnished paper, tear index (13.4 mN.m2/g), tensile index (71Nm/g), Burst index (4.8 KN/g) and folding endurance (82) recommend the cellulosic pulp from Sugarcane Bagasse obtained from the MEA process for strengthening the virgin fiber in recycled papers and also for developing certain types of printing and packaging papers. Due to the awareness towards the negative impact of kraft mill’s effluent to the environment recently, soda pulping started to regain its popularity among the pulp mills especially non-wood based pulp mills. MEA process is more economically attractive given its high pulp yield, despite the significant increase in chemical demand for bleaching. MEA pulping is a good alternative to soda pulping furnishing high pulp yield with less cooking temperature, i.e. 150oC, thereby saving a considerable amount of energy with less odoriferous pollutants and pollution load associated with the soda process.

The accelerated ageing of wood in terms of heating or iron rusting has a potential effect on the physio-mechanical, chemical and biological properties of wood. The effects of accelerated ageing on the mechanical, physical and fungal activity properties of some wood materials (Schinus terebinthifolius, Erythrina humeana, Tectona grandis, Pinus rigida and Juglans nigra) were studied after several cycles of heating and iron rusting. The fungal activity was assayed against the growth of Aspergillus terreus, Aspergillus niger, Fusarium culmorum and Stemphylium solani. In addition, the mechanical and optical properties of paper sheets produced from those wood pulps by means of Kraft cooking were evaluated. The mechanical and chemical properties of the studied wood species were affected significantly (p < 0.05) by the accelerated ageing, compared to control woods. With Fourier transform infrared (FTIR) spectroscopy, we detected an increase in the intensity of the spectra of the functional groups of cellulose in the heated samples, which indicates an increase in cellulose content and decrease in lignin content, compared to other chemical compounds. For pulp properties, woods treated by heating showed a decrease in the pulp yield. The highest significant values of tensile strength were observed in pulp paper produced from untreated, heated and iron-rusted P. rigida wood and they were 69.66, 65.66 and 68.33 N·m/g, respectively; we calculated the tear resistance from pulp paper of untreated P. rigida (8.68 mN·m2/g) and T. grandis (7.83 mN·m2/g) and rusted P. rigida (7.56 mN·m2/g) wood; we obtained the values of the burst strength of the pulp paper of untreated woods of P. rigida (8.19 kPa·m2/g) and T. grandis (7.49 kPa·m2/g), as well as the fold number of the pulp paper of untreated, heated and rusted woods from P. rigida, with values of 195.66, 186.33 and 185.66, respectively. After 14 days from the incubation, no fungal inhibition zones were observed. Accelerated ageing (heated or iron-rusted) produced significant effects on the mechanical and chemical properties of the studied wood species and affected the properties of the produced pulp paper.

The pulp and paper industry has a high potential to contribute to negative emissions through carbon capture and storage (CCS) applied to existing processes. However, there is a need to investigate how CCS solutions also can be combined with implementation of other emerging technologies in pulp and paper mills. This paper investigates the integration of a novel calcination process in two kraft mills and evaluates its potential combination with capture and storage of CO2 from the calcination plant. The alternative calcination process uses electric gas-plasma technology combined with steam slaking and allows replacing the conventional fuel-driven lime kilns with a process driven by electricity. The novel calcination process generates a pure, biogenic, CO2 stream, which provides an opportunity to achieve negative emissions at relatively lower costs. The potential reduction of greenhouse gas emissions when replacing the lime kiln with the plasma calcination concept depends strongly on the emissions intensity of grid electricity, and on whether fossil fuel or biomass was used as a fuel in the lime kiln. If fossil fuel is replaced and electricity is associated with very low emissions, avoided CO2 emissions reach ~50 kt/a for the smaller mill investigated in the paper (ca 400 kt pulp per year) and almost 100 kt/a for the larger mill (ca 700 kt pulp per year). Further emission reductions could then be achieved through CCS from the electrified calcination process, with capture potentials for the two mills of 95 and 164 kt/a, respectively, and capture and storage costs estimated to 36–60 EUR/tCO2.

The alarming global deforestation rate has great impacts on the output of the Pulp and paper Industry since wood is the principal papermaking fiber material. Although, generally, bamboo is an alter...

In this study, action of ultrafiltered xylano-pectinolytic enzymes from a bacterial strain has been evaluated for bleaching of rice straw soda-anthraquinone pulp. Maximum bio-bleaching effect and release of non-cellulosic impurities were noticed with xylano:pectinolytic enzymes dose of 6.0:2.1-IU/g pulp, treatment time of 180 min at 10% pulp consistency, pH 8.5, and temperature 55 °C. Microscopic images of bio-bleached rice straw pulp also confirmed the efficacy of ultrafiltered enzymes, as bleaching agent. This bio-bleaching treatment resulted in 15.38% and 32% reduction in kappa number and active chlorine dioxide dose, respectively, along with increase in various physical properties, burst index (12.50%), tear index (19.07%), breaking length (14.30%), double fold number (26.31%), Gurley porosity (45.32%) and viscosity (16.17%). This bio-bleaching approach not only improved the pulp quality but also reduced environmental pollution load by decreasing effluent parameters values of BOD and COD by 23.67% and 27.44%, respectively. This study indicates that use of ultrafiltered xylano-pectinolytic synergism for rice straw pulp bleaching will ultimately help in making the process eco-friendly, along with better quality pulp. This is the first report on use of ultrafiltered xylanase and pectinase, produced from a bacterial isolate, for bleaching of rice straw pulp.

This study aimed to evaluate the effect of nanocellulose addition on the physical–mechanical properties of the paper produced from different fiber blends, besides comparing two nanocellulose addition methods. Three different fibers were used for fiber blending (eucalyptus, sisal, and pine). Handsheets were formed based on the mixing of all possible combinations at a 45/55 ratio in 2% consistency and 60 g/m2. Handsheet reinforcements were performed by two methods: The mixture method (MT) was a mixture of nanocellulose along with pulp during paper formation in 3, 5, and 10% addition; the coating method (CT) was the superficial coating of dry formed papers in 10% addition. Nanocellulose was produced by mechanical microfibrillation of sisal pulp. Handsheets were evaluated by physical and strength properties. Nanocellulose addition increased thickness, volume, grammage, apparent density, opacity, roughness, tensile strength, tensile index, stretch, bursting index, tear index, and fold endurance by 8.7, 8.8, 10.4, 2.1, 4.1, 23.2, 45.7, 31.8, 20.1, 14.2, 21.1, and 271.6% but reduced bulk, brightness, and air permeance by 1.9, 3.4, and 71.7%, respectively. The reinforcement methods presented distinct results. In physical properties, an increasing tendency toward nanocellulose (MT) increase was observed in thickness, grammage, and apparent density despite the decreasing trend in air permeance. No tendency was observed in other physical properties. In general, CT presented higher values of thickness, grammage, bulk, and brightness but lower values of apparent density and opacity, compared to MT. The mixture method showed an increasing tendency in strength properties with the increase of nanocellulose content. CT obtained fewer strength properties compared to MT.

Nowadays, leaving industrial wastewater into receiving environment causes serious environmental problems. In this study, experimental studies on color and chemical oxygen demand (COD) removal of paper industrial wastewater were carried out. In this context, heterogeneous Fenton and photocatalytic oxidation processes were applied and removal efficiencies were compared. The Fe(III)/MnO2 catalyst containing 8% w/w of iron ion was synthesized to be used in experimental studies. The effects of parameters such as pH, catalyst amount, hydrogen peroxide concentration and reaction time were investigated. At the end of the experimental studies, 90% color and 55% COD removal efficiencies were obtained in heterogeneous Fenton process after 120 minutes reaction time under optimum conditions. After 60 minutes reaction time under the same optimum conditions, 97% color and 91% COD removal efficiencies were achieved in photocatalytic oxidation process.

Nanofibrillated cellulose (NFC) and a combined systems of NFC with cationic starch or cationic polyacrylamide were used in place of long-fiber chemical pulp in manufacturing currency paper from waste lint fibers from the textile industry. Handmade papers (60 g) were produced from each treatment, and the physical, mechanical, and optical characteristics of papers were compared. The results showed that increasing amounts of NFC by itself increased tensile strength, resistance to bursting, tearing, porosity, and opacity, and decreased the resistance to folding and brightness. Increasing NFC in combination with cationic starch reduced the need for chemical pulp, while improving porosity, opacity, and brightness and increased tensile strength, bursting strength, resistance to tearing, and folding in comparison to the use of long-fiber pulp. Increasing NFC in combination with cationic polyacrylamide, compared to long-fiber chemical pulp, increased opacity, tensile strength, and resistance to bursting and decreased the porosity, resistance to tearing, folding, and brightness. Field emission-scanning electron microscopy results showed that an enhanced percentage of NFC reduced porosity so that addition of 5% cellulosic nanofiber made the paper surface smoother and pores were relatively filled.

Detecting the concentration of free chlorine is important for monitoring the quality of water. In this study, we report a nanohybrid paper-based chemiresistive sensor that can be used with smartphones to detect free chlorine ions. The sensor was fabricated using a simple and standardized coating process. The graphene and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) nanohybrid paper-based sensing device exhibited a more stable and intuitive response to free chlorine than that exhibited by the device using only PEDOT:PSS. The nanohybrid paper-based sensor was sensitive to free chlorine concentrations in a linear range of 0.1-500 ppm, and the limit of detection was 0.18 ppm. The sensor showed specificity for free chloride ions and detection capability in samples. The sensor was integrated as a module with an electric readout system, and the measured signals and results could be displayed in real time on a smartphone. Therefore, the proposed sensing platform is suitable owing to its portability, low cost, ease of use, and capability for on-site water quality measurement.

Bentonite and polyamidoamine epichlorohydrin (PAE) resin were added sequentially as a binary system to improve the properties of the paper, especially the wet strength. The results showed that the dry tensile index, the wet tensile index, and the folding endurance of the paper could be improved with only the use of polyamide polyamine epichlorohydrin resin. However, a binary system of polyamide polyamine epichlorohydrin resin and bentonite was more effective. When 0.8% polyamide polyamine epichlorohydrin resin and 0.75% bentonite were added, the dry tensile index, the wet tensile index, and the folding endurance of the paper increased by 37.8%, 2780%, and 281%, respectively, when compared to the control sample. The measurements of the water retention value and the percent fines retention of the pulp showed higher values after being treated with the binary system than being treated by polyamide polyamine epichlorohydrin resin alone. Scanning electron microscopy analysis indicated that a binary system of polyamide polyamine epichlorohydrin resin and bentonite could increase the combination of fibers in paper.

In this paper hemicellulose was separated by using 1-ethyl-3-methylimidazolium acetate (EmimAc, an ionic liquid) -water mixtures from a paper grade market bleached hardwood kraft pulp to produce dissolving pulp. Pure EmimAc dissolves pulp fibers completely in 30 min at ambient temperatures. By adding water (as an antisolvent to EmimAc system) the cellulose dissolution decreases and by optimizing the conditions, hemicellulose is largely removed while cellulose remains as the solid residue (dissolving pulp). At optimal conditions: molar ratio of water to EmimAc of 2, 60 °C, an alpha-cellulose content of 92.2%, with a high yield (78 wt%) was obtained. The viscosity of the solvent mixture decreases by increasing water to EmimAc molar ratio, which improves the mobility of ions, thus, facilitating their penetration into pores and lumens of the fibers during the dissolution process. Cellulose purity increases and purified cellulose yield decreases with the increases in temperature and water content (up to 2 wt%) in the mixture. This study implies that the optimal EmimAc/water mixture is an effective system to separate hemicellulose from hemicellulose/cellulose matrix.

The aim of this paper was to enhance paper strength in NaOH/thiourea aqueous solution at room temperature. Paper from cotton pulp was saturated with room temperature NaOH/thiourea aqueous solution and placed at a fixed temperature (8, 15, and 20 °C) for a period of time (1 h, 2 h, 4 h, and 6 h). The morphology, X-ray diffraction (XRD), mechanical properties, and density of paper were characterized. The results indicated the paper was self-reinforced. Scanning electron microscopy (SEM) photographs indicated that the structure of the treated papers was increasingly compact with decreasing temperature. The XRD results showed that the crystallinity degree of the paper decreased from 80.0% to 60.0%. The stress at break of the treated papers increased by more than fivefold. The wet tensile strength of the treated papers increased remarkably.

The utilization of branchwood as lignocellulosic raw material source for paper production may have the potential of solving the problem of the availability of raw material in the pulp and paper industry. This study therefore compared the chemical composition and fiber morphological indices (according to Franklin’s method) of stemwood and branchwood in Eucalyptus camaldulensis and Pinus halepensis trees grown in Egypt. The statistical analysis showed a significant effect of species, wood type (stem and branchwood), and their interaction on the measured chemical constituents and fiber morphological indices at 0.05 significance level. In both genera, the stemwood exhibited a higher percentage of cellulose and hemicellulose and was lower in lignin, total extractives, and ash than those measured in branchwood. Also in both genera, the stemwood was higher in fiber length, Runkel ratio, rigidity coefficient, Muhlsteph ratio, and Luce’s shape factor, and lower in basic density and flexibility coefficient than those in branchwood. Based on the chemical analysis and the fiber morphological indices, the stemwood and branchwood of both species were suitable for paper production with various qualities. Moreover, good correlations were found in both stem and branchwood between the basic density and the fiber wall thickness and fiber lumen diameter. ln contrast, there was an independent association between the stemwood basic density and the fiber length, and this relationship in branchwood was positive for both genera.

Lime mud, a kind of industrial waste that produced in paper mill, was proposed as CO2 sorbent in calcium looping process. The carbonation performance of the lime mud was investigated in a dual‐fixed bed reactor (DFR) and a thermogravimetric analyzer (TGA). The carbonation kinetics of the lime mud in the chemical reaction controlled stage was analyzed by a surface reaction‐controlled kinetic model. The results show that the lime mud presents much poorer carbonation performance during the chemical reaction controlled stage compared with the limestone, mainly due to the high content of chlorine in the lime mud. A prewash treatment process was used to decrease the chlorine content to mitigate the sintering of the lime mud when calcined at high temperature. After prewash treatment, the prewashed lime mud shows much higher CO2 capture capacity during the chemical reaction controlled stage compared with the lime mud. A prolonged carbonation process successfully further enhances the microstructure and improves the carbonation performance of the prewashed lime mud in the chemical reaction controlled stage. The lime mud can be effectively used as CO2 sorbent in calcium looping process after prewash treatment and the following prolonged carbonation treatment.

A superhydrophobic paper with excellent robustness was fabricated by roll coating with modified nano-TiO2. First, nano-TiO2 particles were hydrophobically modified by γ-aminopropyltriethoxysilane and 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (POTS). Then the paper coating composed of modified nano-TiO2 particles as pigments and epoxy resin (EP) as adhesives was coated on a paper surface to create the desired surface morphology and surface energy. Compared with the uncoated filter paper, the prepared paper showed an improved rough surface morphology owing to the uniform layer of TiO2 microclusters deposited on the fiber network. The superhydrophobic paper exhibited water contact angles (WCA) about 153° ± 1.5°, and water sliding angles (WSA) about 3.5° ± 0.5°, low surface adhesion and excellent bounce ability. The superhydrophobic paper can withstand a variety of wear and tear, such as tape stripping and knife scraping. The as-prepared superhydrophobic paper showed mechanical durability even after 20 wear cycles with sandpaper,thus sustaining excellent superhydrophobicity on the filter paper surface. Moreover, it remains fully functional even in environments with high concentrations of acid and alkali for 96 h. The superhydrophobicity was not affected after storage for 6 months in a natural environment. It was confirmed that the superhydrophobic paper surface exhibited excellent chemical stability, long-term stability and self-cleaning properties. The entire production process was operated under normal environment, without complex equipment; and, as such, has the possibility for large-scale production and application in industry.

Defect spots degrade paper quality and often cause sheet breaks and other problems in the subsequent coating process. We encountered sporadic surges of defect spots on paper from a paper machine producing printing and writing grades of paper. We found that white or light-colored filler spots and waxy, translucent, elliptical spots accounted for 27.3 and 34.4% of these defects, respectively, and that both types of defect contained unhydrolyzed AKD as a major component. Paper machine’s wet-end deposits, however, did not contain unhydrolyzed AKD as a deposit component. We hypothesized that the colloidal stability of AKD was the main factor causing the increase in spot defects, and we verified this by deposit testing experiments. Among the papermaking additives tested, bentonite caused the most significant increase in AKD deposition during testing, which was attributed to its causing the electrostatic coagulation of cationically charged AKD emulsion particles. In contrast, anionically charged AKD emulsions showed improved stability and less deposit formation in the presence of bentonite.

The potential to modify pulp and paper properties by oxygen delignification was assessed by looking beyond the ordinary purpose of oxygen delignification. Pulps with the same kappa number were obtained by both pulping and the combination of pulping and oxygen delignification, and the mechanical and chemical properties were compared. The oxidation of pulp components leads to an increase in carboxylic acid groups in the fibers, resulting in a large influence on fiber swelling, seen as an increase in the water retention value and fiber saturation point. The introduction of charged groups appears to replace some of the morphological changes caused by refining and enhance the strength of fiber–fiber joints, generating pulps with better refinability and higher tensile strength. Oxygen delignification was able to improve the tensile index with 6% at the same sheet density and less refining energy, when the amount of total fiber charges was higher than 140 μekv/g. QC 20220301

Fluorine-free cellulosic paper was successfully obtained by coating the glassine base paper with eco-friendly cellulosic coating, which was made from dissolving cellulose in 8 wt% NaOH/12 wt% urea aqueous solution. Then the coated paper was severally immersed into CH3COOH, Na2SO4, and H2O solution to coagulate and regenerate. Benefiting from the compact matrix and fully covered surface, the resultant cellulosic paper exhibited favorable barrier properties and mechanical performance. Notably, the paper coagulated with CH3COOH displayed the reduction in water–vapor transmission rate, air permeability, and uptake of organic solvents due to its low porosity (26.8%) and narrow pore size distribution (0.1–0.36 µm). The tensile strength and elongation at break of papers treated by CH3COOH at coating weight of 5 g/m2 were increased by 72.1% and 34.0%, respectively. In summary, the fluorine-free cellulosic paper with high oil and grease resistance is attractive for the development of high-performance materials for food packing applications. Fluorine-free paper was obtained from the glassine base paper coated with eco-friendly, non-fluorinated, and degradable cellulosic coating, then coagulated with CH3COOH, Na2SO4, and H2O solution, respectively. The resultant functional papers displayed enhanced barrier properties (oil, organic solvent, vapor, and gas) and mechanical performance.

The use of nanocelluloses is being conducted for the most diverse applications. Their performance as coating agent has been mainly explored to improve barrier properties, as they emerge as perfect candidate for plastic substitution, but it is also important to explore their potential to improve printing quality. In the present work, the influence of different nanocelluloses, obtained through mechanical, enzymatic, TEMPO-mediated oxidation and carboxymethylation treatments, in the coating process and inkjet printability of office papers was assessed. The results revealed that the cellulose nanofibrils are better for printability than the microfibrils. But the size and charge of the former must be taken into account, since fibrils of very small size penetrate the paper structure, dragging the pigments from the surface, and very anionic nanofibrils can also have negative influence on the optical density. Besides, an interesting synergy between surface-sizing starch and the cellulose nanofibrils was found to occur as the latter closed the paper structure, which prevented starch from penetrating, while potentiating both of their positive effects on ink pigment entrapment. An additional study of characterization of inkjet pigments was also performed.

Chitosan is a biopolymer that has shown promising results for surface treatment of paper to enhance barrier and mechanical properties. Commercially, chitosan is available with a wide range of degree of deacetylation (DD). Herein, effect of DD on performance of chitosan in surface application of paper is investigated. Surface application of chitosan of different DD (77%, 84% and 94%) was done at a dose of 1.0 ± 0.2 g/m2 on kraft paper and comparison in terms of strength, structural, surface and barrier properties of paper was performed. Different DD of chitosan was confirmed by FTIR analysis. Results showed that breaking length of paper maximally increased by 15.2%/26.6% in machine direction (MD)/cross direction (CD), respectively after surface application of 94% DD chitosan followed by 77% DD and 84% DD. The maximum increase in burst index, stretch in MD and TEA in both directions of paper was found after surface application of 94% DD chitosan. Results attained by 77% DD and 84% DD chitosan for improvement in burst index, stretch and tensile energy absorption of paper were also encouraging. Maximum increase in stiffness was observed in CD with application of 84% DD chitosan. Double fold of paper also increased the maximum after surface application of 84% DD chitosan. The best results of contact angle, surface energy, Cobb60 and water vapor transmission rate were attained after surface application with 94% DD chitosan whereas the results attained by 77% DD and 84% DD chitosan for contact angle, surface energy, Cobb60 were also encouraging.

Coated paper substrates are used for a wide range of applications. The biggest challenge that remains unsolved with regard to coated paper is its recyclability. Herein, we report a unique approach ...

Greenhouse gas (GHG) emission levels are causing concern as climate change risks are growing, emphasizing the importance of GHG research for better understanding of emission sources. Previous studies on GHG emissions for the pulp and paper industry have ranged in scope from global to regional to site-specific. This study addresses the present knowledge gap of how GHG emissions vary among paper grades in the US. A cradle-to-gate life cycle carbon analysis for 252 mills in the US was performed by integrating large datasets at the production line level. The results indicated that one metric ton of paper product created a production weighted average of 942 kg of carbon dioxide equivalent (kg CO2eq) of GHG emissions. Greenhouse gas emissions varied by pulp and paper grade, from 608 kg CO2eq per metric ton of product to 1978 kg CO2eq per metric ton of product. Overall, fuels were the greatest contributor to the GHG emissions and should be the focus of emission reduction strategies across pulp and paper grades.

This study aims to analyze the effect of managing the diversity of human resources on the performance of employees of PT. Lontar Papyrus Pulp & Paper Industry. The study population was all employees of PT. Lontar papyrus pulp & paper industry, West Tanjung Jabung Regency, totaling 3,023 people. the size or number of samples in this study is determined based on the theory developed by Slovin with a value of e = 10%, so that a sample of 97 people is obtained. The approach in this study uses a quantitative approach to the survey method and uses Partial Least Square (PLS) data analysis. But before the analysis, the outer model test is first performed through the validity and reliability test. Furthermore, the Inner Model test is carried out through the R-Square (Coefficient of determination) and F-Square (f2 effect size) tests. The results showed that the management of diversity in human resources affected the performance of the employees of PT. Lontar Papyrus Pulp & Paper Industry. management of diversity in human resources affected the performance of the employees of PT. Lontar Papyrus Pulp & Paper Industry.

In this study, the viability of acetylation in cellulose fibers waste (CFW) from pulp and paper mill sludge was investigated in comparison to bleached cellulose fibers (BCF). Four acetylation metho...

In this study, different methods for incorporating mixed or laminar copper microparticles (CuMPs) during papermaking were evaluated to determine the optimum paper-making process and correlate particle concentration and shape with antimicrobial activity. The addition of CuMPs during the disintegration of dry pulp stage was observed to produce a paper with uniformly distributed CuMPs, as determined through optical microscopy and UV–Vis spectroscopy analyses by measuring absorbance spectra in different areas of papers. Determination of two indices related to the concentration and distribution of copper will allow to predict the copper content in other papers. CuMP-paper samples were evaluated for structural, optical, and mechanical strength properties according to paper industry standards. Quantitative analyses by atomic absorption showed that between 24 and 39% of CuMPs were embedded in the paper fibre, independent of particle type. Finally, antibacterial activity analyses were performed according to ISO 20645 and ISO 20743. The results showed that papers with 0.30 g of incorporated CuMPs have antimicrobial activity, independent of particle morphology, with effects observed towards Gram (+) and Gram (−) bacteria and fungus. Furthermore, the evaluation of antimicrobial activity at different times of exposure to the microorganisms showed differences in effects that were dependent on the shape of the CuMPs incorporated into paper, where laminar particles exerted a sufficient effect, while no or a slight effect was observed for mixed CuMPs against Aspergillus niger.

This study aims to predict financial distress in pulp and paper companies in Indonesia. The data used are the financial statements of each pul and paper company listed on the Indonesia Stock Exchange in 2012-2017. Data analysis techniques used descriptive analysis with three methods of financial distress prediction, namely the Altman Z-Score, Springate, and Zmijewski methods. The results showed that the Zmijewski method is a prediction method with the highest accuracy rate of 100%, with an error type of 0%. The Altman Z-Score method has an accuracy rate of 28.6%, with an error type of 71.4%. While the Springate method has an accuracy rate of 14.3%, with an error type of 85.7%. Therefore an accurate prediction method to predict the potential for financial distress is the Zmijewski method.

In the current study, an attempt has been made to scale up microfibrillated cellulose (MFC) reinforced paper using a pilot scale Experimental Paper Machine (XPM) in continuous mode. Complete retention of MFC (≈2 nm–10 μm in diameter) on the XPM (using 150 wire mesh, 100 μm pore size) was not possible. Consequently, a “mixed/hybrid” approach was followed using pulp fibers (≈25 μm diameter) as the supportive phase. The produced dense network (≈3 μm pore size) of long pine fibers on wire mesh (100 μm pore size) might be responsible for holding MFC by introducing hydrogen bonds in the continuous production of paper on the XPM. Thereafter, an increase in MFC retention was further observed using additives (cationic starch and anionic silica microparticles) and a maximum 23.4 wt% of MFC in the final paper was calculated. The highest retention (73%), adequate water drainage time (

The application of pulp and paper fibers as reinforcement in thermoplastic composites involves several advantages, such as sustainability, constant fiber quality and high mechanical properties. This work compares three different processing methods for the production of paper-reinforced polypropylene composites. The composites were produced by (i) hot pressing, (ii) injection molding and (iii) a pre-coating process with fiber volume fractions between 10 and 65%. The mechanical properties were investigated by tensile and flexural testing. Furthermore, SEM analysis and porosity determination were carried out. The results were correlated with the according processing method and evaluated towards the highest composite performance. As a result, laminated composites with intact paper layers, showed significantly higher mechanical properties, due to the fiber orientation in the paper sheet and good adhesion between the matrix and the paper fibers. Compounded and injection molded composites showed a high degree of fiber agglomeration and less orientated fibers in the composite leading to reduced mechanical properties.

In the present article we report a new hybrid microfluidic device (hyFlow) comprising a disposable paper electrode and a three-dimensional (3D) printed plastic chip for the electrochemical detection of a magnetic bead-silver nanoparticle (MB-AgNP) bioconjugate. This hybrid device evolved due to the difficulty of incorporating micron-scale MBs into paper-only fluidic devices. Specifically, paper fluidic devices can entrap MB-containing conjugates within their cellulose or nitrocellulose fiber matrix. The hyFlow system was designed to minimize such issues and transport MB conjugates more efficiently to the electrochemical detection zone of the device. The hyFlow system retains the benefit of fluid transport by pressure-driven flow, however, no pump is required for its operation. The hyFlow device is capable of detecting either pre-formed MB-AgNP conjugates or conjugates formed in-situ formation. The detection limit of AgNPs using this device is 12 pM, which represents just 22 AgNPs per MB.

Low consistency (LC) refining of (chemi-)thermomechanical pulp (TMP) provides an energy efficient alternative to high consistency refining for pulp property development. However, the benefit of LC refining is often limited by excessive fibre shortening, lower tear strength and a reduction of bulk caused by the refining process. In this study, microfibres produced by LC refining of TMP and kraft pulp fibres were investigated for their reinforcement potential in high freeness mechanical pulp. Primary pulp at 645 mL Canadian Standard Freeness was LC refined to different energy targets as a baseline for mechanical and optical property development. In contrast, the same primary pulp was reinforced with different microfibre types in ratios that yielded the same specific energies of the baseline LC refined pulp. The study revealed that at equivalent energies, the addition of TMP microfibres to the high freeness primary pulp displayed tensile development identical to the LC refined pulp, with significantly improved tear and bulk. The addition of kraft microfibre to primary pulp produced the highest tensile and tear strength but compromised light scattering. Additionally, all microfibre composites showed improved elongation, as opposed to no notable change in elongation with conventional LC refining. This investigation proposes an alternative, cost-effective approach for developing high bulk, high strength mechanical pulp by limiting the extent of second stage refining and using LC refined microfibres for pulp reinforcement. The high tear–high bulk open construction of the composite paper is likely to benefit boxboard and packaging applications.

The poor barrier properties and hygroscopic nature of cellulosic paper impede the wide application of cellulosic paper as a packaging material. Herein, a polyvinyl alcohol (PVA)-based polymer coating was used to improve the barrier performance of paper through its good ability to form a film. Alkyl ketene dimer (AKD) was used to enhance the water resistance. The effect of the absorptive characteristics of the base paper on the barrier properties was explored, and it was shown that surface-sized base paper provides a better barrier performance than unsized base paper. Nanoclay (Cloisite Na+) was used in the coating formulation to further enhance the barrier performance. The results show that the coating of PVA/AKD/nanoclay dispersion noticeably improved the barrier performance of the paper. The water vapor transmission rate of the base paper was 533 g/m2·day, and it decreased sharply to 1.3 g/m2·day after the application of a double coating because of the complete coverage of the base paper by the PVA-based polymer coating. The coated paper had excellent water resistance owing to its high water contact angle of around 100°. The grease resistance and mechanical properties of the base paper also improved after coating. This work may provide inspiration for improving the barrier properties of packaging paper through the selection of a suitable base paper and coating formulation.

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted the need for versatile diagnostic assays that can discriminate among emerging variants of the virus. Here we report the development and performance benchmarking of an inexpensive (approximately US$0.30 per test) assay for the rapid (sample-to-answer time within 30 min) colorimetric detection of SARS-CoV-2 variants. The assay, which we integrated into foldable paper strips, leverages nucleic acid strand-displacement reactions, the thermodynamic energy penalty associated with single-base-pair mismatches and the metal-ion-controlled enzymatic cleavage of urea to amplify the recognition of viral RNAs for the colorimetric readout of changes in pH via a smartphone. For 50 throat swab samples, the assay simultaneously detected the presence of SARS-CoV-2 and mutations specific to the SARS-CoV-2 variants Alpha, Beta and Gamma, with 100% concordance with real-time quantitative polymerase chain reaction and RNA sequencing. Customizable and inexpensive paper-based assays for the detection of viruses and their variants may facilitate viral surveillance.