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This paper investigates the influence of thermal pretreatment on kinetic parameters based on four kinetic models: Modified Gompertz, transference and logistic functions and first order equation. The kinetic modeling was applied on experimental results of previous study on producing methane from anaerobic digestion of Recycled Pulp and Paper Sludge (RPPS) under mesophilic conditions. We observed that the thermal pretreatment improve considerably improved the kinetic parameters mainly the methane production rate and the lag phase. Indeed, it can be noted that methane production rate μ increases significantly from a value of 4.72 to 16.27 Nml/h using logistic function for 1 g VS/L added load. Then the lag phase parameter λ has dramatically decreased from 5.46 to 1.04 h using logistic function for 1,5g VS/L added load. This means that the thermal pretreatment of RPPS accelerates the methane production process and saves time.

Biodegradable paper cups coated with rice bran wax and whey protein isolate were designed to package popcorn. Coatings with different concentrations of whey protein isolate (5.5, 7.75, and 10% w/v) and rice bran wax (0.2, 0.4, and 0.6% w/v) were applied on the outer surface of the paper cups. Thickness, color changes, Young's modulus and tensile strength, water vapor transmission rate (WVTR) of the coated and uncoated cups, and also popcorns properties (pH, texture, and sensory properties) were evaluated. Water vapor transmission rate, Young's modulus, thickness, total color change index, and tensile strength of coated cups with the optimal coating formulation was 19.785 (g/m2 day), 11.810 (MPa), 276.583 (µm), 1.839, and 11.222 (MPa), respectively. The results showed that paper cup coating increased thickness and yellowness and reduced the brightness, Young's modulus, and WVTR. Coating had a positive effect on the pH and texture of popcorns packaged in coated cups than samples packed in uncoated cups (p, Biodegradable packaging is one of the best types of packaging that wishes not to harm the environment. Paper packaging coated with materials, such as rice bran wax and whey protein isolate, both of which are food waste, can improve paper color and resistance, and provide a good moisture barrier. This type of coating can be used in paper packaging of food such as snacks, noodle packaging, semi‐prepared foods, etc. This type of packaging can also maintain the physicochemical and sensory properties of food for a long time. Also, due to the edible nature of this type of coating, this coating can be used inside the package so that the printability of the packaging surface is not affected.

In this study, it was aimed to investigate the chemical and morphological suitability of using pseudo-stem which are formed in large amounts during the fruit harvesting of the banana plant (Musa sapientum) with a widespread agricultural area in the world, as raw material in the paper industry. The main chemical constituents of banana pseudo-stem holocellulose, α-cellulose and lignin were determined as %77.5, %51.0 and %12.7, respectively. Hot water solubility was 17.3%, cold water solubility 13.0%, alcohol and 1% NaOH solubility values were 9.2% and 33.3%, respectively. It has been determined that banana pseudo-stem waste fibers, which are similar to softwood fibers in terms of fiber length and hardwood fibers in terms of fiber width, have high slenderness and flexibility ratios with low Runkel ratio, rigidity coefficient and Mühlstep ratio. The results obtained from chemical and morphological analyzes indicated that banana pseudo stem waste is a suitable raw material for pulp and paper production., Bu çalışmada dünyada yaygın bir tarım alanına sahip muz bitkisinin (Musa sapientum) meyve hasadı sırasında oldukça fazla miktarda oluşan gövde atıklarının, kağıt endüstrisinde hammadde olarak kullanılabilirliğinin kimyasal ve morfolojik açıdan uygunluğunun araştırılması amaçlanmıştır. Muz yalancı gövdesinin başlıca kimyasal bileşenleri holoselüloz, α-selüloz ve lignin sırasıyla %77.5, %51.0 ve %12.7 olarak tespit edilmiştir. Sıcak su çözünürlüğü %17.3, soğuk su çözünürlüğü %13.0, alkol ve %1 NaOH çözünürlük değerleri ise sırasıyla %9.2 ve %33.3 olarak bulunmuştur. Lif uzunluğu bakımından iğne yapraklı ağaç odunu liflerine, lif genişliği bakımından ise yapraklı ağaç odunu liflerine benzeyen muz yalancı gövde atığı liflerinin düşük Runkel oranı, rijitlik katsayısı ve Mühlstep oranı ile yüksek narinlik ve esneklik oranlarına sahip olduğu tespit edilmiştir. Kimyasal ve morfolojik analizlerden elde edilen sonuçlar, muz yalancı gövde atıklarının kağıt hamuru ve kağıt üretimi için uygun bir hammadde olduğunu göstermiştir.

The rapid economic growth and environmental concerns have led to high demands on paper and paper-based products in terms of variety, quantity, quality, and specialty. Enhancement and functionalization with additives are constantly required. Moving away from traditional petroleum-based additives, researchers have attempted to use “green” nanoadditives by introducing renewable environmentally friendly nanocellulose. This article studies the functions of nanocellulose as bio-additives (enhancer, retention and filtration reagent, and coating aid) in paper and paper products, and overviews the research development of nanocellulose-based additives and their applications in the paper industry for both efficient production and paper functionalization. The review shows that (1) a variety of nanocellulose-based bioadditives have been reported for various applications in paper and paper-based products, while commercially viable developments are to be advanced; (2) nanocellulose was mostly formulated with other polymer and particles as additives to achieve their synergistic effects; (3) major interests have concentrated on the nanocellulose in the specialty papers as representing more value added products and in the efficient utilization of recycled fibers, which remains most attractive and promising for future development. This report shall provide most useful database information for researchers and industries for paper recycling and enhancement, and paper-based products innovation and application.

Natural yellow plant dyes and traditional medicines were used widely on historical papers in ancient China for religious reasons and conservation considerations. This study aims to evaluate some traditional yellow botanical sources of dyes that contain different chemical colorant compositions in order to understand their effects on the properties of traditional handmade paper. The physical and chemical changes in paper specimens treated with plant dyes were studied by examining properties such as the color, pH, thermogravimetric (TG) characteristics, tensile strength, folding endurance and microstructure by scanning electron microscopy (SEM). The results indicated that different colorants had different toning effects and that the main components, including carboxyl and ketone groups, could affect the paper stability at high temperatures. The results also revealed that the mechanical properties of paper specimens were improved after treatment with plant dyes. The significant improvements in the tensile strength and folding endurance and the slightly higher decomposition temperature of Amur cork tree-dyed paper could be ascribed to the strong interaction between the colorants’ main components and the fibers. The scientific evaluation of the property changes is therefore valuable information for weighing the advantages and disadvantages of the various yellow toning materials for paper conservation treatment.

Background and Objectives: The use of endophytic fungi for management of phenol residue in paper and pulp industries has been shown as cost-effective and eco-friendly approach. In this study, isolation of endophytic fungi from roots, stems, and leaves of Hibiscus sabdariffa was conducted. Additionally, the isolated fungi were examined for their ability to degrade phenol and its derivatives in paper and pulp industrial samples, using different growth conditions. Materials and Methods: Out of 35 isolated endophyitc fungi, 31 were examined for their phenol biodegradation capacity using Czapek Dox broth medium containing Catechol and Resorcinol as a sole carbon source at final concentrations of 0.4, 0.6 and 0.8%. Results: A total of 35 fungal species belonging to 18 fungal genera were isolated and identified from different parts of H. sabdariffa plants. All strains have the capability for degrading phenol and their derivatives with variable extents. The optimum condition of degrading phenol in paper and pulp effluent samples by Fusarium poae11r7 were at pH 3-5, temperature at 28-35°C, good agitation speed at no agitation and 100 rpm. Conclusion: All endophytic fungal species can utilize phenol and its derivatives as a carbon source and be the potential to degrade phenol in industrial contaminants.

A wide variety of biomass is available all around the world. Most of the biomass exists as a by-product from manufacturing industries. Pulp and paper mills contribute to a higher amount of these biomasses mostly discarded in the landfills creating an environmental burden. Biomasses from other sources have been used to produce different kinds and grades of biomaterials such as those used in industrial and medical applications. The present review aims to investigate the availability of biomass from pulp and paper mills and show sustainable routes for the production of high value-added biomaterials. The study reveals that using conventional and integrated biorefinery technology the ample variety and quantity of waste generated from pulp and paper mills can be converted into wealth. As per the findings of the current review, it is shown that high-performance carbon fiber and bioplastic can be manufactured from black liquor of pulping waste; the cellulosic waste from sawdust and sludge can be utilized for the synthesis of CNC and regenerated fibers such as viscose rayon and acetate; the mineral-based pulping wastes and fly ash can be used for manufacturing of different kinds of biocomposites. The different biomaterials obtained from the pulp and paper mill biomass can be used for versatile applications including conventional, high performance, and smart materials. Through customization and optimization of the conversion techniques and product manufacturing schemes, a variety of engineering materials can be obtained from pulp and paper mill wastes realizing the current global waste to wealth developmental approach.

Fraudulent papers from paper mills are a serious threat to the entire scientific community. Naunyn-Schmiedeberg’s Archives of Pharmacology has become the target of a massive attack of fraudulent papers originating from paper mills. This editorial highlights 20 important features we observed with paper mills and explains how the journal is responding to this serious threat to restore the integrity of science. Hopefully, this editorial is also helpful for editors of other scientific journals.

Achieving an efficient catalyst in the ATRP system with a simple design, preparation from available materials, and high recyclability is a significant challenging issue. To attain the goal, herein, we used chitosan (CS)-modified cellulose filter paper (FP) as a green support for the synthesis of dip catalyst. The preparation of this catalyst involved surface treatment of the FP strips by CS coating through a dipping method, which increased the affinity of the substrate for adsorbing copper ions in the next step. The Cu@CS-FP catalyst was prepared without the requirement of any ligands. The synthesized dip-catalyst, in the form of the strips, was employed for the first time in the ATRP reaction of methyl methacrylate to assay catalytic activity. Catalytic insertion/ removal (ON/OFF) experiments were carried out during the polymerization. A reasonable control over the molecular weight with high conversion (68%) and polydispersity index of 1.32 under mild reaction conditions were obtained. Significantly, because of the facile separation of the catalyst, the amount of copper that remained in the polymer was very low (2.7 ppm). Also, the recyclability of the catalyst was investigated for five runs. The conversion in the final run was 64% without a loss of catalyst efficiency.

[EN] Recent trends in waste management have initiated interest in recycled materials for sound absorption applications. The present paper studies the possibility of paper sludge to be recycled as material for sound absorption applications. Paper sludge (PS) is the water treatment waste, produced during paper production. Two different methods were studied to produce paper sludge and slaked lime composite acoustic panels for sound absorption applications at low and mid-frequencies. The sound absorption coefficient of paper sludge composite panels is measured in an impedance tube using the two-microphone method. The samples produced with different methods showed different behaviours of sound absorption. The primary method to produce showed acoustic asymmetry in the vertical direction of the samples, and it was considerably fragile as well. An improved method to produce PS composite panels was proposed in this paper. Using this method, homogenous and robust acoustic panels were obtained., The authors would like to kindly thank the technician Javier Zaragoza Dolz and Dr. Olga Kizinievi for their fruitful suggestions on this study. This research was financially supported by the Ministry of Science and Innovation and the European Union FEDER through Project PID2019-109175GB-C22

The paper discusses a self tuning control algorithm for a multivariable plant applied to a grammage cross profile control of a paper machine. The plant model represents the steady-state couplings as well as the dynamics behaviour of the system. The control algorithm handles special situations including the case where the numper of measurments is not equal to the numper of actuators and the case where special actuators are locked. The whole identification algorithm with a specical filter and an estimation of the required measurment accuary for a succesful identification of the steady-state couplings will be discussed. The paper shows how to proof the stability of the control system including the cases of locked actuators and identification errors. Finally, the whole conrol system is verified by in house simulations and at a real plant. The obtained control results are discussed.

Energy isan important in put for economic and industrial development and anindispensable production input for the continuation of the production process.In a very large part of economic and social life, electrical energy is widelyused because of its easy usage and other advantages. The aim of this study isto investigate the effect of the production of paper and paper products and thegross national product, which is an indicator of economic growth, on theconsumption of electricity by panel data analysis. For this purpose, a paneldata set was established for 20 OECD countries between 2006 and 2016 fromEurostat and Wordbank. Cross-sectional dependence, heteroskedasticity andautocorrelation assumptions were tested for the model and deviations from theassumptions were observed. Parameters were estimated using the Driscoll-Kraayestimators, which are resistant to these deviations. As a result of theanalysis, it was found that an increase of 1% in the production of paper andpaper products increased the electrical energy consumption by 0.22%, the increaseof 1% in the per capita gross domestic product increased approximately 0.62% inelectricity consumption., Enerji,ekonomik ve endüstriyel kalkınma için önemli ve üretim sürecinin devamı içinvazgeçilmez bir üretim girdisidir. Kolay kullanım ve diğer avantajlarısebebiyle ekonomik ve sosyal yaşamın oldukça geniş bir bölümünde yaygın olarakelektrik enerjisinden yararlanılmaktadır. Bu çalışmanın amacı, kağıt ve kağıtürünleri üretimi ve ekonomik büyümenin bir göstergesi olan gayri safi millihasılanın elektrik enerjisi tüketimi üzerindeki etkisini panel veri analizi ileincelemektir. Bu amaç doğrultusunda, Eurostat ve Wordbank’tan elde edilen2006-2016 yılları arasında 20 OECD ülkesi için panel veri seti oluşturulmuştur.Model için yatay kesit bağımlılığı, değişen varyans ve otokorelasyonvarsayımları sınanmış ve varsayımlardan sapma olduğu görülmüştür. Bu sapmalaradirençli Driscoll-Kraay tahmin edici kullanılarak parametreler tahminedilmiştir. Analiz sonucunda, kağıt ve kağıt ürünleri üretiminde meydana gelecek%1’lik bir artış elektrik enerjisi tüketimini %0.22 oranında, kişi başıgayri safi milli hasıladaki %1’lik bir artışın ise elektrik tüketimindeyaklaşık olarak %0.62 dolayında arttırdığı bulgusuna ulaşılmıştır.

Refereed/Peer-reviewed At a paper manufacturing mill (PML) that had been previously part of an integrated pulp (bisulphite) and paper mills industry, cyanobacterial blooms were observed in the mill’s aerated stabilization basin (ASB) ponds at about 3 years after pulping had been discontinued. This study aimed to determine the factors that led to bloom occurrences and potential control strategies applicable to the paper manufacturing mill’s, aerated stabilization basin system that discharges wastewaters into a coastal lake. Following discontinuation of pulping, the colour of the wastewaters reduced to low levels (~ 10 Hazen units or less), while the levels of nutrient remained potentially supportive of cyanobacteria growth with total phosphorus at ~ 0.1 mg/L and total nitrogen at > 2.5 mg/L. Incidences of blooms in the ABS were associated with preceding average monthly rainfalls and wind speeds being less (~ 44% and ~ 7%, respectively) and average direct sunlight hours being greater (~ 9%) than the long-term average values. Zinc was investigated for control of cyanobacteria as this metal is less toxic to aquatic organisms and microflora than copper algaecides. In laboratory culture trials, zinc was found to inhibit growth of M. aeruginosa (strain MIC338) and Pseudanabaena sp. when dosed at ~ 2.5 mg/L. The inhibition of cyanobacteria by zinc was found to vary between ASB pond samples which had different in situ chlorophyll a levels. This study found that the PML wastewaters investigated can be supportive of cyanobacterial growth to bloom levels after discontinuation of pulping processes and that zinc has potential as a cyanobacteria control agent.

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

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

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.

A paper-based membraneless direct hydrogen peroxide fuel cell was developed and tested under different potassium hydroxide concentrations (1 to 7 mol lt-1, stepping by 2), different hydrogen peroxide concentrations (1, 2, 3 mol lt-1) and different temperatures (20, 30, 40oC). Moreover, the developed fuel cell was studied for stability under stopped and continuous flow conditions. From the experiments, it was found that the maximum power density of 6.79 mW cm-2 and the maximum open circuit voltage of 0.87 V at 40oC were obtained when the anode solution consisted 2 mol lt-1 H2O2 and 5 mol lt-1 potassium hydroxide and cathode solution consisted 2 mol lt-1 sulfuric acid and 2 mol lt-1 hydrogen peroxide. It was found that if the reactants were supplied constantly into the fuel cell, a current density of 3.12 mA cm-2 was obtained. The developed fuel cell produced energy for 91 minutes when the reactant flow was stopped.

Paper derived from lignocellulose has great advantages over plastics as packaging material, nevertheless, the poor water- and oil-resistances of paper-derived products limited their application in high-end field. Herein, novel dimer acid-based waterborne polyurethanes (DWPUs) with different content of dimer acid-based polyester polyol (DG) were prepared and used as water- and oil-resistant coating for paper substrate. The effects of DG contents on water- and oil-resistances, mechanical properties and thermal stability of DWPUs coated papers were systematically investigated. When the content of DG reached up to 7 wt% (based on polyester glycol), the paper coated by DWPU exhibited 88.06% decrease in Cobb 60 value, 8.7 times increase in kit rating compared with uncoated paper. Meanwhile, DWPUs coated papers showed good mechanical properties and thermal stability. These improvements are attributed to the flexible long-alkyl chain, and six-ring structure of DWPUs as well as the continuous and homogeneous DWPU-derived membrane on the surface of paper. This study provides a new framework for the preparation of high quality, multifunctional, environmentally friendly water- and oil-resistant coatings for paper substrates.

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.

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.

PURPOSE: Main insight of the study was to evaluate the potential of Perionyx excavatus, an indigenous earthworm of India towards bioconversion of toxic paper mill wastes. The study had considered a comprehensive study over succession of different enzymes and microbial biomasses alongside removal of heavy metals to reflect the qualitative enrichment of the toxic waste through valorisation procedure. METHODS: The process of vermicomposting was performed using ratio of paper mill sludge: cow dung: straw as 5:4:1 and Perionyx excavatus for a period of 60 days. Qualitative enrichment was considered through detailed evaluation of physicochemical parameters and succession of 19 enzymes using API ZYM technology. Heavy metal loads in terms of Zn, Cr, Cu, Pb along with bioaccumulation factor (BAF) were considered to establish functional role of earthworm in bioremediation. Microbial succession was measured in terms of PLFA biomarkers. RESULTS: Enzymatic enrichment of different isozymes of esterase, aminopeptidase and glycosyl hydrolase were found in the vermicompost. A significant reduction of heavy metals was noticed in vermicomposting of primary sludge as Zn > Pb > Cr > Cu and secondary sludge as Zn > Pb > Cu > Cr. An increase in density of Gram positive bacterial and fungal populations was found at the end phase of vermicomposting process which supports maturity of vermicompost. CONCLUSION: Presence of different enzyme activities, reduction of heavy metal loads along with rise of eukaryotic PLFA markers, had illustrated the efficiency of vermicomposting as a valorisation procedure in the qualitative enrichment of toxic organic paper mill sludge.

Waste paper is often underutilized as a low-value recyclable resource and can be a potential source of cellulose nanofibers (CNFs) due to its rich cellulose content. Three different processes, low acid treatment, alkali treatment and bleaching treatment, were used to pretreat the waste paper in order to investigate the effect of different pretreatments on the prepared CNFs, and CNFs obtained from bleached pulp boards were used as control. All sample fibers were successfully prepared into CNFs by 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) oxidation. It was quite obvious that the bleached CNFs samples showed dense fibrous structures on a scanning electron microscopy (SEM), while needle-like fibers with width less than 20 nm were observed on a transmission electron microscopy (TEM). Meanwhile, the bleaching treatment resulted in a 13.5% increase in crystallinity and a higher TEMPO yield (e.g., BCNF, 60.88%), but a decrease in thermal stability. All pretreated CNFs samples showed narrow particle size distribution, good dispersion stability (zeta potential less than −29.58 mV), good light transmission (higher than 86.5%) and low haze parameters (lower than 3.92%). This provides a good process option and pathway for scalable production of CNFs from waste papers.

This Editorial introduces a Special Issue of papers from the SEE International Conference RADAR 2019, which took place in Toulon, France, 23–27 September 2019. The papers are expanded versions of ones that were judged in the reviewing process to be of the highest quality and relevance. Benefitting from the unique location of the conference centre on the French Riviera, the conference was given the theme ‘Sensing from sea to space’, attracting nearly 400 attendees from 26 countries from all over the world (Figure 1). Engineers and researchers coming from private or public sector (universities and laboratories) shared their knowledge and experience on radar topics of common interests from physics to signal processing, from sensor validation to system design, and also on emerging technologies based on artificial intelligence; all topics being supported by 200 papers presented either in oral (150 papers in 36 sessions), or poster sessions (50 papers). Figure 2 shows the range of topics of the papers. 1 FIGURE Conference attendees by country 2 FIGURE Conference paper topics

The electrochemical activity of catalysts strongly depends on the uniform distribution of monodisperse Pt nanoparticles without aggregates. Here, we propose a new hydrolysis-assisted smearing method for Pt loading on a free-standing paper-type electrode. Polyacrylonitrile (PAN)-based nanofiber paper was used as the electrode, and it acted as a Pt support. Hydrolysis of the electrode tripled the number of active nucleation sites for Pt adsorption on the PAN nanofibers, thereby significantly enhancing the wettability of the nanofibers. This facilitated the uniform distribution of Pt nanoparticles without aggregate formation up to 40 wt% (about 0.8 mg/cm2) with a particle size of about 3 nm. The catalytic current of the hydrolyzed Pt electrode in CH3OH/H2SO4 solution exceeded 213 mA/cm2 Pt mg, which was considerably greater than the current was 148 mA/cm2 Pt mg for an unhydrolyzed electrode.

In this paper, a method for preparing a high-stability superhydrophobic paper with temperature-induced wettability transition is proposed. First, a temperature-responsive superhydrophobic triblock polymer PHFMA–PTSPM–PNIPAAm was prepared by one-step polymerization of TSPM, HFMA, and NIPAAm in a mass ratio of 0.3:0.3:0.3, then a superhydrophobic paper with a good temperature response was successfully prepared by grafting amino-modified SiO2 with the polymer to modify the surface of the paper. A further study found that when the mass ratio of amino-modified SiO2 to polymer is 0.2, the coating has good superhydrophobicity and transparency. What is more, the prepared modified paper is in a superhydrophobic state when the temperature is higher than 32 °C, and is in a superhydrophilic state when it is lower than 32 °C, which can realize free conversion between superhydrophobic and superhydrophilic states. In addition, the superhydrophobic paper prepared by this method not only has high oil–water separation efficiency, and the superhydrophobic coating shows good stability and transparency, but also has low requirements of environmental conditions for preparation, relatively simple preparation process, and strong repeatability, and it has a very broad application prospect.

The paper presents the results of copper electroless metallization of cellulose paper with the use of a polydopamine coating and silver catalyst. The polydopamine coating was deposited via a simple dip method using a dopamine hydrochloride solution in 10 mM TRIS-HCl buffer with a pH of 8.5. The research showed that as a result of this process, cellulose fibers were covered with a homogeneous layer of polydopamine. The unique properties of the polydopamine coating allowed the reduction of silver ions from silver nitrate solution and the deposition of silver atoms on the paper surface. Deposited silver served as a catalyst in the autocatalytic electroless copper-plating process. The copper layer covered the entire surface of the paper sheet after 5 min of metallization, favorably affecting the electrical properties of this material by lowering the surface resistivity. The deposited copper layer was further characterized by good adhesive strength and high susceptibility to deformation.

The present study was carried out to evaluate the effects of different fungal species on the metal uptake from paper sludge by Hemarthria compressa L. Paper sludge (PS) in various concentrations (0, 30% and 60%) were used with four treatments of two fungal species (F0 = Control, F1 = Aspergillus niger, F2 = Trichoderma pseudokoningii, F3 = A. niger + T. pseudokoningii). Paper sludge as rooting medium steadily influenced growth and physio-biochemical attributes of H. compressa in F0. Results revealed discrete variations in growth attributes with different PS concentrations and each fungal treatment. The maximum damages in ionic homeostasis (Na+, K+, Ca2+, Mg2+) due to PS toxicity were evident in parallel with declined chlorophyll concentration. The highest growth, total chlorophyll and biomass of the plants were observed when PS was treated with combined fungal strains (F3). Translocation factor decreased with F3 that is indicative of changes in Cd, Pb, and Cu movement to shoot from root. The plants with combined fungal treatment also showed greater catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) activity. Ions, such as Ca, Mg, and Na, also increased gradually with combined fungal treatment. The correlation matrix displayed a close association among diverse fungal and PS levels with multiple plant attributes. PCA-Biplot confirmed the outcome of correlational analyses among different characters of H. compressa. The combined fungal mediate the extraction of heavy metals from the paper sludge by H. compressa recommends the high accumulation of heavy metal (HM) and possible reutilization of metal free sludge as a fertilizer, for application in cultivated fields. Furthermore, the effects of fungal species on HM attenuation in PS are linear and can be used in different habitats. Advancement in such research work will also be helpful in understanding the mechanisms and enhancing the ability of other native microbes to remediate metals.

A novel material for the deacidification and protection of paper has been designed by using MgO filled halloysite nanotubes (Hal). The ability of MgO loaded nanotubes to control the acidic conditions was evaluated by pH measurements in aqueous solvent. Afterwards, paper was impregnated into hydroxypropyl cellulose dispersions containing the consolidating material. A simulation of strong acidic conditions allowed us to evaluate the deacidification effect of the composite material on the samples. In particular, the paper reaches a pH of 7.7 after 1 h exposition to HNO3 vapours when MgO-Hal nanoparticles are added to the impregnation mixture at a concentration of 10 wt% and it remains still neutral after 12 h. Dynamic mechanical analysis showed that the tensile strength of the consolidated paper is improved, since the stress at breaking increase of ca. 8% for the samples treated with MgO-Hal compared to the untreated paper. Due to the presence of halloysite loaded with the alkaline reservoir, the acidic degradation of cellulose is neutralized as suggested by the stored energy which is similar to the pristine paper without any chemical attack. Therefore, the mechanical performances of the paper are preserved during the aging together with its macroscopic aspect, as suggested by colorimetric analysis. The proposed consolidation protocol represents a further step for the self-healing and long-term protection of cellulose based artworks.

Regenerated papers made from discarded natural sources, such as seaweeds or non-wood plants, are viewed as promising eco-friendly alternatives relative to conventional wood-based paper. However, due to its limited mechanical strength and higher water absorption than compared to traditional wood paper, it often results in premature structural disintegration. In order to overcome this limitation, this research introduces an efficient and comprehensive strategy of coating seaweed and plant papers with varying concentrations and molecular weights of chitosan. Increased concentration and molecular weight resulted in a greater amount of chitosan deposition, while the highest molecular weight also shows increased dissolution of soluble components of the paper. Since plants and seaweeds contain high anionic polysaccharide contents, the cationic chitosan shows high binding affinity towards paper. The resulting chitosan-coated papers demonstrate significant enhancements in water repellency and mechanical properties. In addition, the chitosan-coated papers also show significant bacterial inhibition effects due to the natural anti-microbial activity of chitosan.

In this research work, the effect of three (3) pulping additives such as polysulfide, Anthraquinone and surfactant used in the monoethanolamine (MEA) pulping of agro-biomass, their possible interactions and synergy effect on pulp screened yield were investigated. The pulping conditions of the digester were adjusted so that the experimental design considered the following factors and levels: 75% MEA charge, 150oC cooking temperature, 90minutes cooking time, 4 to 1Liquor- Biomass ratio. Factor 1: 0, 0.25 and 0.5% Surfactant charge, Factor 2: 0, 2.0 and 4.0% polysulfide charge, Factor 3: 0, 0.25 and 0.5% anthraquinone charge. The Agro-biomass was evaluated in terms of pulp screened yield. Heating time ranged from 5 to 45minutes and maximum cooking time did not exceed 90minutes, liquor biomass ratio was 4 to 1 and Liquor charge was 75% MEA. The yield for MEA with 4% Polysulfide (PS) dosage without the inclusion of Surfactant and Anthraquinone was highest (59.08%) in all the twenty seven (27) experimental runs, but furnished the highest reject (12.26%) and an unimpressive screened yield of 46.82% standing amongst the least possible outcomes. The yield for MEA with 0.25% Anthraquinone (AQ) dosage without the inclusion of Surfactant and Polysulfide furnished a total yield of 50.32%, pulp screened yield of 50.03% with a minimal reject of 0.29 showing to be more efficient than the use of polysulfide. Monoethanolamine (MEA) pulping with 0.5% surfactant (Surf.) dosage without the inclusion of other additives i.e. AQ and PS achieved 51.12% total screened yield with a reject of only 0.33% furnishing the highest pulp screened yield (50.79%) thereby showing more efficiency amongst the three (3) pulping additives investigated in this research study base on single use. However, the result obtained from the combination of the three (3) pulping additives furnished the highest screened yield (52.43) with 4.23% reject in scenario E, experiment No. 15, involving the combination of 0.25% surfactant, 0.25% anthraquinone and 4% polysulfide charge showing the best synergistic effect. Although the highest screened yield (53.04% and the least reject (0.13%) indicating the best possible outcome amongst the entire twenty seven (27) experimental runs came from the combination of 0.25% surfactant and 2% polysulfide charge. If we have to consider the use of surfactant and polysulfide alone, the best possible outcome came from the combination of 0.25% surfactant and 2% polysulfide charge in experiment 20 of scenario G. Analyses of the overall experimental results show that there is considerable advantage and a positive synergy effect in the use of additives in pulping operation.

This paper investigates the potentials of a novel environmental friendly pulping (Monoethanoleamine-MEA) process in comparison with conventional Soda and Kraft pulping processes in furnishing high yield pulp from agro-biomass for the formation Papers and other paper products. The pulping investigation had three (3) factors at three (3) different levels each: Factor 1, MEA concentration (50, 75 and 100%); Factor 2, cooking time (60, 90 and 120minutes); Factor 3, liquor-biomass ratio (4, 6 and 8) at a fixed temperature of 123±5oC. Consequently, the experimental design had 27 treatments (3×3×3) and 2 replicates. By using a central composite factorial design, equations relating the dependent variable (pulp yield) to the different independent variables (cooking temperature, cooking time and liquor concentration) were derived; reproducing the experimental result for the dependent variable with errors less than 15%. Models were evaluated to analyze the effect of experimental pulping conditions on pulp properties and evaluate the effect of these properties on furnished paper samples. Pulp Screened Yields was in the range of 42.45 to 49.18% calculated on oven dry (O.D) basis. The resultant pulps obtained from the cooking operation had very good appearance, exhibiting fairly bright color, with slow tendency to felt, thereby making drainage and consequent paper making time short. It is recommended that the cellulosic pulp obtained from MEA pulping of EFB is appropriate as virgin fiber for strengthening secondary fibers in recycled papers and also for developing certain types of writing, printing and packaging paper materials. Conclusive investigation on EFB fiber in this research study asserts that it has a promising future (when used in blend with certain long fiber plant i.e. kenaf) in substituting wood in the pulp, paper and fiber- board industry. Conclusive investigation also asserts from over-all parameter achieved that monoethanolamine-MEA when used as the main de-lignifying agent furnished pulp and subsequent paper with good strength properties that can adequately match those from conventional (i.e. kraft and soda) processes and because it works without the use of sulphur compounds, it attributes a particular benefit of simple MEA recovery by distillation, allowing black liquor combustion to be dispensed and the dissolved lignin recovered without negative impact on the environment.

Based on the use of Hevea brasiliensis in latex production, the species has a consolidated role in the Brazilian economy. However, at the end of the production cycle, which lasts from 25 to 30 years, resulting wood, in general, has no added value and is normally used for firewood, without further exploring its technological properties. Seeking to introduce this species into the pulp and paper industry, we aimed to determine the fiber quality of 20 commercial clones. Wood samples were collected from planted trees (11 to 12 years old) in the municipality of Selvíria - MS. We calculated wood quality indexes of H. brasiliensis for cellulose and paper, including Flexibility coefficient, Wall proportion, Runkel ratio, Slenderness ratio (Aspect ratio), and Luce's Shape Factor. The fiber quality indexes that best indicate the potential use of wood from Hevea brasiliensis clones for cellulose and paper production were Wall Fraction, Runkel Ratio and Luce's Shape Factor, indicating that H. brasiliensis fibers, if used for proper industrial purposes, will give origin of a rigid paper with greater bonding contact on the surface. The clones that presented better results for fiber quality indexes were IAC 311, IAC 41, IAN 873, IAC 326, IAC 40 and RRIM 725. Enabling the use of wood after the latex exploratory cycle for pulp and paper will serve as a basis for genetic improvement of these clones and expansion of forest plantations for this purpose. Atribuido al uso de Hevea brasiliensis en la producción de látex, una especie tiene un papel consolidado en la economía brasileña. Sin embargo, al final del ciclo de producción, que dura de 25 a 30 años, la madera resultante, por lo general, no tiene valor agregado y se utiliza normalmente en la producción de leña, sin conocimiento de sus propiedades tecnológicas. Con el objetivo de introducir esta especie en la industria de la pulpa y el papel, nos propusimos determinar la calidad de la fibra de 20 clones comerciales. Se recolectaron muestras de madera de árboles plantados (de 11 a 12 años) en la ciudad de Selvíria - MS. Calculamos los índices de calidad de la madera de H. brasiliensis para pulpa y papel: coeficiente de flexibilidad, fracción de pared, índice de Runkel, relación de esbeltez (relación de aspecto), factor de forma Luce. Los índices de calidad de la fibra que mejor indican el uso potencial de madera de clones de Hevea brasiliensis para la producción de celulosa y papel fueron: Wall Fraction, Runkel Ratio y Luce Form Factor, lo que indica que las fibras de la especie son utilizadas por los orígenes diseñados por la industria. a un papel rígido, con mayor contacto de unión en la superficie. Los clones con los mejores índices de calidad de fibra fueron IAC 311, IAC 41, IAN 873, IAC 326, IAC 40 y RRIM 725. Habilitar el uso de madera después del ciclo exploratorio del látex para pulpa y papel y servir como base para la mejora genética de clones y expansión de plantaciones forestales para estos metales. Devido ao uso de Hevea brasiliensis na produção de látex, a espécie tem um papel consolidado na economia brasileira. No entanto, ao final do ciclo produtivo, que dura de 25 a 30 anos, a madeira resultante, em geral, não apresenta valor agregado e é normalmente utilizada na produção de lenha, sem conhecimento de suas propriedades tecnológicas. Buscando introduzir esta espécie na indústria de celulose e papel, objetivamos determinar a qualidade das fibras de 20 clones comerciais. Amostras de madeira foram coletadas de árvores plantadas (11 a 12 anos) no município de Selvíria – MS. Calculamos os índices de qualidade da madeira de H. brasiliensis para celulose e papel: coeficiente de flexibilidade, fração de parede, índice de Runkel, razão esbeltez (razão de aspecto), fator de forma de Luce. Os índices de qualidade das fibras que melhor indicam o potencial emprego da madeira dos clones de Hevea brasiliensis para a produção de celulose e papel foram: Fração Parede, Razão Runkel e Fator de Forma de Luce, indicando que as fibras da espécie se utilizadas pela indústria dará origem a um papel rígido, com maior contato de união na superfície. Os clones que apresentaram melhores índices de qualidade das fibras foram IAC 311, IAC 41, IAN 873, IAC 326, IAC 40 e RRIM 725. Possibilitando a utilização da madeira pós ciclo exploratório do latéx para a celulose e papel e servindo de base para melhoramento genético desses clones e ampliação dos plantios florestais para essa finalidade.

Research on paper made from coconut and tofu waste has been carried out using the alkalization method of separation technique, with the optimum composition as follows: NaOH concentration used is 3.0% and cooking temperature is 100 0C and the time required is 90 minutes. The results of the catheterization test of paper made from coconut dregs and tofu have a water content of 3.2%; pH 6.9, pulp content 65.75%; cellulose content 80.22%; lignin content 18.27%. The results of the FT-IR spectrum analysis of coconut pulp and tofu pulp are suitable for use as raw materials for making paper because they contain cellulose fibers. This is indicated by the appearance of the O-H hydroxyl group which is observed at a wavenumber of 3312 cm-1. Based on the SEM results, the surface morphology of the coconut pulp and tofu combination paper shows that the surface structure is the denser the fiber bonds, the smaller the fiber diameter, the better the mechanical properties. The results of the research conclusions explain that, paper made from coconut and tofu waste has met the requirements set by SNI 14-0444-1989. Keywords: Paper, Cellulose, Coconut pulp, Tofu pulp, Lignin

Currently, there is an increasing interest in the use of biopolymers in industrial applications to replace petroleum-based additives, since they are abundantly available, renewable and sustainable. Cottonseed protein is a biopolymer that, when used as a modifier, has shown improved performance for wood adhesives and paper products. Thus, it would be useful to explore the feasibility of using cellulose nanomaterials to further improve the performance of cottonseed protein as a paper strength agent. This research characterized the performance of cottonseed protein isolate with/without cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs) to increase the dry strength of filter paper. An application of 10% protein solution with CNCs (10:1) or CNFs (50:1) improved the elongation at break, tensile strength and modulus of treated paper products compared to the improved performance of cottonseed protein alone. Further analysis using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) indicated that the cottonseed protein/nanocellulose composites interacted with the filter paper fibers, imparting an increased dry strength.

Broader use of bio-based fibres in packaging becomes possible when the mechanical properties of fibre materials exceed those of conventional paperboard. Hot-pressing provides an efficient method to improve both the wet and dry strength of lignin-containing paper webs. Here we study varied pressing conditions for webs formed with thermomechanical pulp (TMP). The results are compared against similar data for a wide range of other fibre types. In addition to standard strength and structural measurements, we characterise the induced structural changes with X-ray microtomography and scanning electron microscopy. The wet strength generally increases monotonously up to a very high pressing temperature of 270 °C. The stronger bonding of wet fibres can be explained by the inter-diffusion of lignin macromolecules with an activation energy around 26 kJ mol−1 after lignin softening. The associated exponential acceleration of diffusion with temperature dominates over other factors such as process dynamics or final material density in setting wet strength. The optimum pressing temperature for dry strength is generally lower, around 200 °C, beyond which hemicellulose degradation begins. By varying the solids content prior to hot-pressing for the TMP sheets, the highest wet strength is achieved for the completely dry web, while no strong correlation was observed for the dry strength.

Valorization of industrial low-value side-streams are of great interest, contributing to boosts in the circular economy. In this context, lignin side-streams of the pulp and paper industry were oxypropylated to produce biobased polyols and tested in the synthesis of rigid polyurethane (RPU) foams. E. globulus lignins, namely a lignin isolated from an industrial Kraft black liquor and depolymerized lignins obtained as by-products of an oxidation process, were used. RPU foams, synthesized with 100% lignin-based polyols and using a 1.1 NCO/OH ratio, were characterized concerning apparent density, morphology, thermal conductivity, thermal stability, and heat release rate (HRR). Foams containing the lignin-based polyols presented densities varying from 44.7 to 112.2 kg/m3 and thermal conductivity in the range of 37.2–49.0 mW/mK. For the reference foam (sample produced with 100% wt. Daltofoam TP 32015 polyol), values of 70.9 kg/m3 and 41.1 mW/mK were obtained, respectively. The achieved results point out the viability of using the generated lignin-based polyols at 100% content in RPU foams, mainly when depolymerized lignins are used. Moreover, fire retardancy was favored when the lignin-based polyols were introduced. The proposed strategies can contribute to establishing the integrated pulp and paper biorefinery concept where material synthesis (polyols and RPU foams) can be combined with chemical production (vanillin and syringaldehyde). Foundation for Science and Technology (FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UIDB/00690/2020), and to UIDB/50020/2020 of the Associate Laboratory LSRE-LCM—funded by national funds through FCT/MCTES (PIDDAC); national funding by FCT, PI, through the institutional scientific employment program contract for Isabel P. Fernandes. This work was carried out under the Project No. 33969 Bioblocks—Design of biobased products from renewable lignocellulosic sources as precursors for the bioindustry of chemical synthesis and biomaterials—financed by FEDER through the Operational Program for Competitiveness Factors (POFC) and QREN. To COST Action LignoCOST (CA17128) supported by COST (European Cooperation in Science and Technology). info:eu-repo/semantics/publishedVersion

In 2021, the International Council on Large Electric Systems (CIGRE) will celebrate its centenary. CIGRE Sessions are traditionally held face-to-face in Paris once every even-numbered year. However, in 2020, in response to the coronavirus pandemic, the organizers of the 48th CIGRE Session decided to hold a virtual meeting for experts, specialists, engineers, and researchers from all over the world. The result was an e-session that included engaging seminars, tutorials, and discussions. At the virtual meeting, participants discussed various problems and challenges currently affecting all areas of the energy sector. Current pressing issues include the development of informative diagnostic techniques for oil-filled equipment, as well as the potential applicability of environmentally friendly biodegradable synthetic and natural esters for use as liquid insulation in high-voltage equipment. This review presents the latest research, practical solutions and reports on the experience of applying new techniques and novel liquid insulating materials. Valuable and up-to-date information in these fields is provided by experts and specialists from all over the world.

Paper historic relics are of great value to research and preserve. However, with the change of environment, paper cultural relics are constantly aging and damaged. Therefore, the reinforcement and conservation of the paper is an important topic in the field of cultural relics protection, thus, it is a crucial and arduous task to discover high-performance protective materials. The coating reinforcement method is a kind of commonsense method to strengthen the paper. Additionally, it is key to select appropriate reinforcing resins. Polyurethane has influence on the improvement of paper strength, stability, and appearance. The epoxycyclohexane-epoxychloropropane polyether polyol was prepared with epoxycyclohexane and epoxychloropropane as materials, glycerol as the initiator, boron trifluoride diethyl etherate as the catalyst, and dichloromethane as the solvent. Infrared (IR) spectroscopy as well as proton nuclear magnetic resonance (1HNMR) spectroscopy were adopted to characterize the structure of the synthetic copolyether. Then, polyurethane based on epoxycyclohexane-epoxychloropropane was prepared by the synthetic copolyether reacting with hexamethylene diisocyanate (HDI) trimer. The effect of the mass concentration of polyurethane on the tensile strength, elongation, folding endurance, and the tearing strength of paper samples were tested. When 10% polyurethane solution was applied to paper, not only were the mechanical properties greatly improved, but the gloss and brightness also changed slightly, which conformed to the principle of “repair as old”. The above results indicate that the synthetic polyurethane combines the advantages of epoxycyclohexane-poxychloropropane polyether polyol along with polyurethane, presenting excellent properties in paper reinforcement or conservation.

To study the influence of different concentrations of zinc oxide (ZnO)/silicon dioxide (SiO2) composite coating on hydrophobic property and mechanical stability of paper mulch film, three kinds of ZnO/SiO2 composite coating paper mulch films (2%, 4%, 6%) with different coating substance contents were prepared by brush coating method. Through particle size analysis, contact angle, rolling angle and mechanical stability test, combined with scanning electron microscope, three-dimensional morphology and roughness measuring instrument, the optimal concentration of ZnO/SiO2 composite coated paper mulch film was screened out. Through acid-base salt corrosion test, silver mirror reaction and surface self-cleaning, the optimal concentration of composite coated paper mulch film was compared with the original paper mulch film to prove its excellent chemical stability and hydrophobicity. The results show that the paper mulch film with 4% coating material has excellent hydrophobicity and mechanical stability, can effectively reduce the surface roughness of paper mulch film, and has remarkable effects in resisting acid, alkali and salt and self-cleaning.

Sustainable and low-cost cellulose-based metallisation is the prerequisite for wearable and disposable electronics fabrication. In this paper, to realize the simplified, low-cost and high efficient metallisation, a new method had been proposed without both the noble metal activators and the corrosive chemicals. The modified electroless plating processes had been employed in activation and deposition procedure. The nickel ions were first physiadsorbed on the cellulose paper (CP) fibers and then reduced into clusters by reducing agent which can act as the seeds to initiate the electroless plating process. The gold galvanic displacement was conducted further to modify the nickel surface. Via these processes, the cellulose paper was metallised with Ni-P and Au/Ni-P successfully. The morphological and microstructural properties of the resulted Ni-P/CP and Au/Ni-P/CP hybrids were evaluated. The Ni-P/CP composites had a low surface resistance below 0.5 Ω sq-1 while the Au/Ni-P/CP composites are below 0.1 Ω sq-1. The relationship between the mechanical and electrical properties with the plating parameters is discussed. The results indicated that Au/Ni-P/CP had good electrical conductivity and mechanical flexibility. Finally, the application demonstration for supercapacitor with the modified metallisation method was exhibited. This work offers a facile and non-toxic path to develop high-performance metallisation for functional cellulose-based materials.

The use of paper as a sustainable packaging material is favored, but it lacks sufficient barrier properties in terms of water repellence and oil resistance. Novel approaches consider active packaging materials or coatings with controlled release providing additional functionality for delivery of specific components to the surface. In this study, the development of a waterborne coating with organic nanoparticles and encapsulated sunflower oils is presented as a system for thermal release of the oil and on-demand tuning of the final barrier properties of the paper substrate. After synthesis of the nanoparticles, it seems that the encapsulation of various grades of sunflower oil (i.e., either poly-unsaturated or mono-unsaturated) strongly affects the encapsulation efficiency and thermal release profiles. The water contact angles are controlled by the oil release and chemical surface composition of the coating upon thermal heating. The oil resistance of the paper improves as a more continuous oil film is formed during thermal release. In particular, the chemical surface composition of the paper coatings is detailed by means of micro-Raman spectroscopy and surface imaging, which provide an analytical quantification tool to evaluate surface coverage, oil delivery, and variations in organic coating moieties. This research was funded through the Robert-Bosch Foundation in the frame of the Juniorprofessorshhip program, project ‘FORESNAB’ (2011–2016) for acquiring Raman spectroscope and TM3000 microscope. R. Thomann (University of Freiburg) is acknowledged for TEM measurements, and D. Stanssens (Topchim N.V.) is acknowledged for materials supply.

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.

Significance Populations living in remote rural communities would benefit from rapid, highly sensitive molecular, DNA-based diagnostics to inform the correct and timely treatment of infectious diseases. Such information is also becoming increasingly relevant in global efforts for disease elimination, where the testing of asymptomatic patients is now seen as being important for the identification of disease reservoirs. However, healthcare workers face practical and logistical problems in the implementation of such tests, which often involve complex instrumentation and centralized laboratories. Here we describe innovations in paper microfluidics that enable low-cost, multiplexed DNA-based diagnostics for malaria, delivered, in a first-in-human study, in schools in rural Uganda., Rapid, low-cost, species-specific diagnosis, based upon DNA testing, is becoming important in the treatment of patients with infectious diseases. Here, we demonstrate an innovation that uses origami to enable multiplexed, sensitive assays that rival polymerase chain reactions (PCR) laboratory assays and provide high-quality, fast precision diagnostics for malaria. The paper-based microfluidic technology proposed here combines vertical flow sample-processing steps, including paper folding for whole-blood sample preparation, with an isothermal amplification and a lateral flow detection, incorporating a simple visualization system. Studies were performed in village schools in Uganda with individual diagnoses being completed in

Kevlar pulp treated with low-temperature plasma and nano cellulose fibrils (NCFs) have been introduced as reinforcements in the preparation for composite insulating paper with low relative permittivity, dielectric loss, good mechanical properties, and thermal stability. More polar groups of Kevlar fibers could be exposed after plasma treatment. Results showed that the relative permittivity of the composite paper containing 20% Kevlar pulp, 10% NCF, and 70% softwood pulp is decreased by 29.6% and the dielectric loss is decreased by 43.2% at 50 Hz, 25°, compared with the conventional paper formed by pure softwood pulp. The change was due to the introduction of Kevlar pulp with intrinsic low dielectric constant and loss, which decreases the whole polarizability of the paper. The mechanical properties of the composite paper became worse after introducing 20% Kevlar pulp. About 10% NCF can work as a mechanical reinforcement to compensate for the tensile and Yang's modulus loss. Scanning electron microscopy results showed that NCF could fill the void defects and improve the interface bonding of the fibers to enhance the paper mechanical properties. The composite paper also had better insulating and thermal properties than the conventional paper. It has been concluded that the Kevlar pulp/NCF/softwood pulp composite paper has the potential to replace the pure softwood paper for the application of high-voltage ac transformer insulation.