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Background: One of the ongoing challenges in freight transport operations is to balance efficiency, effectiveness, and sustainability through the integration of sustainable practices to minimize the environmental impact. When it comes to truck payload and sustainability, the emphasis is on optimizing space, and minimizing empty miles and the wastage of resources. Ensuring that truck loads meet their targets has many challenges, and our empirical research examines the factors influencing the payloads of recycled fibre across the network in the UK paper industry. Methods: A mixed method approach includes interviews, business process analysis, the identification of opportunity areas, a site visit, simulation, and viability analysis to assess factors as part of the sustainable solution. Results: The research identified aspects related to processes, data availability and fragmentation, consistent procedures, practices, and operational considerations. Refining cage-loading procedures, enhancing baling processes and the visibility of upstream processes, and establishing robust information-sharing mechanisms improve efficiency and support sustainability. Conclusions: The empirical research extends the knowledge related to freight efficiency movements on the road and focuses on practical actions in utilizing recycled fibre's carrying capacity. [ABSTRACT FROM AUTHOR]

The automotive industry is under growing pressure from regulatory agencies to improve the recyclability of its plastic components. Simultaneously, manufacturers are adopting natural fiber composites in vehicles to reduce their carbon footprint and decrease reliance on petroleum-based materials. This presents a challenge at vehicle end-of-life, however, as natural fiber-reinforced polymers are substantially more difficult to recycle than their unreinforced counterparts. This study investigated the development of a mechanical recycling process for paper fiber-reinforced polypropylene composites, focusing on the impact of injection molding parameters—specifically, injection temperature and rate—on the thermal, mechanical, and water uptake properties of the composites. The results showed that processing temperature had a greater influence on composite performance than injection rate, with some limited interaction effects between the two. Higher processing intensity damaged the paper fibers, increasing the number of nucleation sites and resulting in greater polypropylene crystallinity. These structural changes reduced tensile properties at higher intensities, while flexural properties improved. Objective function analysis was applied to identify optimal processing conditions, balancing these competing trends. Overall, the findings demonstrate that paper fiber-reinforced polypropylene composites can be recycled into automotive-relevant injection molding compounds using conventional plastic manufacturing techniques, though careful tuning of processing parameters is essential to achieve optimal performance. [ABSTRACT FROM AUTHOR]

Currently, there is significant competition in recycling waste paper and using it for producing various types of paper used in the packaging sector. The paper derived from recycled pulps lacks good strength due to the gradual shortening of fibers and the reduction in bonding characteristics. Considering this challenge, in this study, after converting old corrugated containers (OCC) into pulp and then refining them, they were oxidized in an alkaline environment using hydrogen peroxide at varying percentages of 0, 0.5, 1, 2, 3, and 4 to create diversity and increase reactive groups. Sodium caseinate was then added to the pulp suspension at levels of 0.5, 1, 2, 3, 4, 5, 6, 7, 8, and 9 percent as a cross-linking agent. Finally, standard handmade papers were produced from them. The status of the formed functional groups was measured by FTIR spectrum, and the mechanical strength and water absorption of the produced papers were measured according to the standards of the Technical Association of the Pulp and Paper Industry (TAPPI). FTIR results showed that the oxidized pulp samples had high absorption at the wavenumber 1650, which corresponds to the carboxyl group. Additionally, the calculation of the carboxyl groups using the methylene blue absorption method indicated that the highest amount of carboxyl groups was in the 1 percent hydrogen peroxide treatment. The addition of sodium caseinate to the pulp suspension significantly increased the mechanical strength of the resulting papers. [ABSTRACT FROM AUTHOR]

Increasing wastewater treatment efficiency is a primary aim in the circular economy. Wastewater physicochemical and biochemical processes are quite complex, often requiring a combination of statistical and machine learning tools to empirically model them. Since wastewater treatment plants are large-scale operations, the limited opportunities for extensive experimentation may be offset by miniaturizing experimental schemes through the use of fractional factorial designs (FFDs). A recycling quality improvement study that relies on non-linear multi-objective multi-parameter FFD (NMMFFD) datasets was reanalyzed. A published NMMFFD ultrafiltration screening/optimization case study was re-examined regarding how four controlling factors affected three paper mill recycling characteristic responses using a combination of statistical and machine learning methods. Comparative machine learning screening predictions were provided by (1) quadratic support vector regression and (2) optimizable support vector regression, in contrast to quadratic linear regression. NMMFFD optimization was performed by employing Pareto fronts. Pseudo-screening was applied by decomposing the replicated NMMFFD dataset to single replicates and then testing their replicate repeatability by introducing belief functions that sought to maximize credibility and plausibility estimates. Various versions of belief functions were considered, since the novel role of the three process characteristics, as independent sources, created a high level of conflict during the information fusion phase, due to the inherent divergent belief structures. Correlations between two characteristics, but with opposite goals, may also have contributed to the source conflict. The active effects for the NMMFFD dataset were found to be the transmembrane pressure and the molecular weight cut-off. The modified adjustment was pinpointed to the molecular weight cut-off at 50 kDa, while the optimal transmembrane pressure setting persisted at 2.0 bar. This mixed-methods approach may provide additional confidence in determining improved recycling process adjustments. It would be interesting to implement this approach in polyfactorial wastewater screenings with a greater number of process characteristics. [ABSTRACT FROM AUTHOR]

Cellulosic/lignocellulosic nanofibers (CNF/LCNF) are value-added products which recently have been considered widely. This study focused on valorization of waste by making CNF from white cutting wastepaper (WCW), which was confirmed by the transmission electron microscope images. The CNF present in the paper recycling process showed significant effects on the final product and process aspects. Addition of 5% CNF (based on dry weight of pulp) to the recycled fibers improved the strength properties as well as the fines retention. But in contrast, the drainage decreased from 303 to 188 mL CSF. Finally, considering the importance of wastepaper history on the quality of recycling process and final products, as a new vision, this study focused on recyclability of wastepaper which has experienced CNF as an additive in their history of papermaking. In this respect, the papers reinforced with nanofibers in their history, after several recycling, experienced less reduction in the tensile and tear indices and fines retention. In summary, it seems that the presence of CNF in the wastepaper can slow down the reduction of product density and process properties during several recycling cycles and so restore their potential for subsequent papermaking cycles. [ABSTRACT FROM AUTHOR]

The momentum of the Fourth Industrial Revolution is driving increased demand for certain specific metals. These include copper, silver, gold, and platinum group metals (PGMs), which have important applications in renewable energies, green hydrogen, and electronic products. However, the continuous extraction of these metals is leading to a rapid decline in their ore grades and, consequently, increasing the environmental impact of extraction. Hence, obtaining metals from secondary sources, such as waste electrical and electronic equipment (WEEE), has become imperative for both environmental sustainability and ensuring their availability. To evaluate the sustainability of the process, this paper proposes using an exergy approach, which enables appropriate allocation among co-products, as well as the assessment of exergy losses and the use of non-renewable resources. As a case study, this paper analyzes the recycling process of waste printed circuit boards (PCBs) by disaggregating the exergy cost into renewable and non-renewable sources, employing different exergy-based cost allocation methods for the mentioned metals. It further considers the complete life cycle of metals using the Circular Thermoeconomics methodology. The results show that, when considering the entire life cycle, between 47% and 53% of the non-renewable exergy is destroyed during recycling. Therefore, delaying recycling as much as possible would be the most desirable option for minimizing the use of non-renewable resources. [ABSTRACT FROM AUTHOR]

The worldwide recycling rate for paper is about 60% and there are ongoing efforts to enhance the recycling rates to 80%. The low strength of recycled paper primarily due to the contaminants in it fetches lower value to the recycled paper in the market and also limits its recyclability. The ways to circumvent the problem of contamination of paper have been addressed by adding additives. However, the use of additives increases the cost of the final recycled paper. Oxidation has been explored as an alternative to enhance the tensile strength of paper in this work as it can be used in existing paper recycling facilities without any modifications. Pulp fibres were collected from an active paper recycling mill and subjected to oxidation at various oxidation levels from 0.25 up to 1.5 mmol/g. It was found that the tensile strength of the paper increased by up to 89% with an increase in oxidation level up to 1 mmol/g and later decreased with a further increase in the oxidation level up to 1.5 mmol/g. The brightness of the paper increased by up to 3% with an increase in oxidation level up to 0.85 mmol/g and then a decrease with further enhancement in the oxidation level. The oxidized samples were also studied with infrared spectroscopy, x‐ray diffraction, electron microscopy, and optical properties to study the behaviour of the resulting material. A ring crush test and corrugating medium test were also performed on the oxidized pulp samples to establish the feasibility of the material for packaging applications. [ABSTRACT FROM AUTHOR]

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually results in models that are inconvenient to implement and/or interpret. In this paper, a comprehensive study of several machine learning methods for the prediction of flotation deinking performance is carried out, including support vector regression, regression tree ensembles (random forests and boosting) and Gaussian process regression. The prediction relies on the development of a limited dataset that assumes representative data samples obtained under a variety of laboratory conditions, including different reagents, pH values and flotation residence times. The results obtained in this paper confirm that the machine learning methods enable the accurate prediction of flotation deinking performance even when the dataset used for training the model is limited, thus enabling the determination of optimal conditions for the paper recycling process, with only minimal costs and effort. Considering the low complexity of the Gaussian process regression compared to the aforementioned ensemble models, it should be emphasized that the Gaussian process regression gave the best performance in estimating fiber recovery (R2 = 97.77%) and a reasonable performance in estimating the toner recovery (R2 = 86.31%). [ABSTRACT FROM AUTHOR]

Abstract This work features a new corona discharge plasma technology for de-inking yellow, blue, and red colors on various papers. This work was developed to minimize the chemical and environmental impacts of de-inking processes. A nonchemical contribution, operating at room temperature and atmospheric pressure, reduces the environmental impact of the process. The deinkability factor (DEMLab) values for all papers are determined with the optimal assessment results provided by a 36-mm variation gap at 2-min (blue) and 10-min (yellow and red) plasma exposure times, followed by applied voltages of 20 kV (yellow), 16 kV (blue), and 20 kV (red). The corona discharge plasma led to 48.58% (yellow printed paper), 64.11% (blue printed paper), and 41.11% (red printed paper) deinkability without altering the physical properties of the paper itself. The change in the tensile strength for the plasma-exposed paper was relatively little, less than 10%, compared to that of common recycling. The tensile strength of the untreated white paper was 5065 ± 487.44 N/mm2, and that of the plasma-treated printed paper was 4593 ± 248.47 N/mm2. It appears that there is little impact on the physicochemical properties of paper induced by the corona plasma treatment during the de-inking process.

The European Community is striving for a sustainable society as suggested by the UN's 2015 sustainability goals. The circular economy in the paper and packaging industry is of particular importance here because it consumes many resources. The paper industry in Germany with a fiber recycling rate of 85% in 2022 is already a pioneer and role model for other industries. All materials should be recyclable. Fiber-based composites/laminates are currently becoming increasingly important. Essential questions are: which collection systems and recycling paths should be used for fiber-based composites/laminates, and where are there currently challenges with recycling? To answer these questions, 58 questionnaires answered by German experts and practitioners in the German paper industry were evaluated. Wet-strength papers, adhesives, plastic coatings and wax dispersions were perceived as a problem by 70% of all respondents, and packaging residues by almost 40%. Additionally, 90% stated that the composition of paper for recycling changes regularly due to legislation, trends and innovations, while 60% attributed this to recent changes in legislation. For at least 80%, virgin fibers from packaging are valuable for paper recycling, but only 15% of respondents stated that virgin fibers compensate for the disadvantages of rejects. Almost 90% expected challenges with fiber-based composites/laminates in the existing paper for recycling processes. Overall, the collection and recycling of fiber-based composites/laminates in conventional paper for recycling collection and the recycling system is not desirable. An integrated collection, sorting and recycling system should be considered, especially because a further increase in fiber-based composites is to be expected. In the end, the design for recycling and following recycling guidelines are the key to the recycling industry in the future. Good recyclability of fiber-based composites/laminates would improve their acceptance by paper recyclers. Their virgin fibers are particularly valuable. The results of our study are relevant to the recycling and fiber industry, standard-setting bodies, regulatory authorities and research. The limitation of this study is that experts from the paper industry were interviewed, but the recyclability of the fiber materials was not analyzed by measurement, and the machine technology of the interviewees could not be examined and evaluated. [ABSTRACT FROM AUTHOR]

Nanocellulose has shown promising improvements in the technological properties of various products within the paper industry. The aim of this research was to evaluate the influence of nanofibrillar cellulose (NCF) from bamboo (Guadua angustifolia Kunth.) on the physical-mechanical properties of paper made with virgin bamboo fiber, recycled fibers from Double Kraft Liner (DKL), and a mix of both. The NCF was obtained by means of TEMPO at a defibrillation of 25 000 RPM. Then, it was added in concentrations of 0, 2, 4, and 6% for each type of paper. The results, which were statistically analyzed, demonstrated that thickness, permeability, and tear resistance decreased, while density and resistance to tension and folding increased as the NCF concentration increased. Due to the characteristics of NCF, the potential use of the paper made with this additive is food wrapping. [ABSTRACT FROM AUTHOR]

The mineralization of inorganic components in paper sludge offers potential for their re-use in various fields. This study synthesized carbonates based on the minerals present in paper sludge and aimed to investigate the control of particle size distribution and particle shape of the synthesized carbonates. First, the physicochemical and thermal properties of paper mill sludge and ash were evaluated using a spectrophotometer, XRF, and TGA. Paper sludge ash was obtained by incinerating the paper sludge, followed by a carbonation reaction using CO2 gas injection and pH neutralization to produce recycled fillers. The average particle size, crystal lattice structure, and morphology of the recycled fillers were analyzed using a particle size analyzer, XRD, and FE-SEM. The results indicate that the recycled filler produced from coating paper sludge exhibited similar brightness and morphology to conventional paper-based fillers, suggesting its potential to replace commercial PCC (Precipitated Calcium Carbonate). In contrast, the recycled filler manufactured using old corrugated container mill sludge was deemed unsuitable due to its low hydration activity. [ABSTRACT FROM AUTHOR]

A pre-treatment process was evaluated in this work for wastewater from paper recycling using microwave technology followed by rapid precipitation of contaminants through centrifugation. Artificial neural networks (ANNs) were used to analyze and optimize the turbidity values. Thirty experimental runs were utilized including microwave (MW) power, duration, centrifuge time, and centrifuge speed as input variables, generated by the Central Composite Full Design (CCFD) approach. The experimental turbidity ranged from 8.1 to 19.7 NTU, while predicted values ranged from 8.4 to 19.7 NTU by ANN. The ANN model showed a robust prediction performance with low mean squared error values during training and testing. Moreover, high R² values showed a remarkable agreement between the experimental observations and ANN predictions. The results obtained from the input values (A:150.00, B:60.00, C:15.00, D:30.00) of sample 2, which gave the lowest turbidity value, showed the most removal of pollution. The results obtained from the input values (A:250.00, B:60.00, C:7.00, D:20.00) of sample 30, which gave the highest turbidity value, showed the least removal of pollution. The results showed that increasing RPM and time of the centrifugation process significantly affected the removal of pollution in wastewater. [ABSTRACT FROM AUTHOR]

It has been clearly demonstrated that it would be feasible to consider recycling paper in an academic institution. This can be achieved through combining specific waste paper baskets, a pulping machine and power supplied by a renewable energy source, with an already established local paper making company. The paper making company would be able to gain a subsidy from the government which pays them to actually recycle paper, to counteract the cost of the pulped paper which is 30% more expensive than raw wood pulp. The academic institution would save money on waste disposal and decrease its carbon footprint by 600% with savings of up to around 5e6 tons of CO2 per year, instead of the 1e2 tones carbon offset for just recycling the paper normally. This entire process could be adapted for recycling the vast quantities of waste paper produced by students, an initiative which often fails due to the high cost of disposal. This could be achieved through urged use of the same paper disposal methods already in use, with the paper being collected and pulped once a week directly from the student paper waste bins. This research aims to study and limit the quantities of paper consumed in academic institutions in Iraq, by identifying the steps of recycling, and the extent of its environmental and economic impact, on the one hand, and on the other hand, the extent to which the Iraqi university community accepts this idea, and then study these quantities and evaluate them economically and find out the possibility of establishing a paper recycling plant based on these quantities. As well as the current research deals with the accumulation of paper waste caused by the performance of exams. In the third semester of the research, the amount of paper waste at Thi Qar University was calculated as a model for conducting a detailed research study of all departments and colleges of the University. the amount of paper waste was (11,055 tons/year), as well as calculating the cost of paper processing for the University amounted to (126252271 Iraqi dinars) and at the end of the third semester, the amount of paper waste in Iraqi academic institutions for the academic year 2022e2023, approximately (367,60976 tons/year). The cost of preparing exam books in Iraqi academic institutions for the academic year 2022e2023 amounted to approximately (4202150971 Iraqi dinars). The devices used in the practical aspect and each device and its purpose in the paper waste recycling process were explained. In addition, in the fourth chapter of the research, waste recycling was carried out in a practical way, and the results were satisfactory. We proposed a project to establish a paper and cardboard waste recycling plant in Nasiriyah, detailing its technical processes and stages in a mature way, the costs of establishing such projects in detail, as well as the annual profit of the project. At the conclusion of the research, some important recommendations were attached that help the paper waste recycling process and its success. [ABSTRACT FROM AUTHOR]

To encourage proper waste management for electrical and electronic devices (e-waste), it is necessary to invest heavily in the development of recycling technologies. One way to improve the process is to automate separating the shredded parts of e-waste using a robot. This paper's literature review, utilizing the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) framework, showcases potential robotic technologies for e-waste separation. However, the intricate design of these devices can pose significant challenges in their implementation. Various legal, organizational, and sociological obstacles have left Serbia's e-waste management practice underdeveloped, resulting in an unsatisfactory recycling rate. In this paper, we examined the possibility of using robots in the precise example of recycling refrigerators in a recycling center in Eastern Serbia, concluding that such a solution would have multiple positive effects, both on the employees and the working environment, on the operations of the recycling center itself, and on increasing the e-waste recycling rate in the country. [ABSTRACT FROM AUTHOR]

This text describes a study that investigates the mechanics, environmental benefits, and potential challenges of paper recycling machines. It highlights the importance of these machines in promoting a more sustainable future, and how they align with the United Nations' Sustainable Development Goals (SDGs). The SDGs aim to address issues such as climate change, land use, responsible consumption and production, and poverty alleviation by promoting sustainable economies. This study explores the transformative potential of the recycling industry and its impact on the economy of Papua New Guinea (PNG). [ABSTRACT FROM AUTHOR]

The US and the EU have adopted contrasting pathways in their pursuit of increased sustainability. This editorial highlights such contrasts with respect to paper and nonwovens products. The American way, at least at the federal level, depends on consumer input, which can have an impact on corporate decisions and practices. Progress with respect to sustainability in the European Union has a higher reliance upon regulations. Each approach has merits as well as deficiencies. A regulation-dependent approach sometimes just moves problems to other parts of the world. A consumer-driven approach does not have a good way to deal with a need for systematic change, such as systems to recycle textile and nonwoven materials. It follows that a combined approach, involving both consumer demand and regulations, can be recommended as a most effective path forward. In addition, applications of artificial intelligence have potential to reconcile societal needs with future industrial practices. [ABSTRACT FROM AUTHOR]

This paper studies the recycling and remanufacturing mode and sales channel issues in the closed-loop supply chain. Specifically, this study establishes an e-commerce closed-loop supply chain consisting of a manufacturer and an e-commerce platform, and divides the recycling model into recycling by the manufacturer or recycling by the platform. Considering two common sales models in e-commerce platforms: the resale model and agency model, combined with the recycling model, four different research scenarios are formed. We use backward induction to solve the Stackelberg game problem and explore the remanufacturing and channel strategies of the manufacturer and the e-commerce platform. The research results show that for the manufacturer, under the same recycling model, when consumers' preference for remanufactured products and the sensitivity of recycling volume to recycling prices are low, he will prefer the resale model. Under the same sales model, the manufacturer always prefers the recycling model in which he is responsible for recycling. However, the choice of platform is contrary to that of the manufacturer. In the resale model, both the manufacturer and the platform will choose to recycle by themselves, which cannot achieve a win-win situation. Under the agency model, when consumers' preference for remanufactured products is high and the sensitivity coefficient of recycling volume to recycling price is low, supply chain members can achieve a win-win situation, and the scope of the win-win situation decreases as the unit production cost of new products increases. In addition, rising consumer preference for remanufactured products will lead to lower consumer surplus. [ABSTRACT FROM AUTHOR]

The advancement of agricultural mesh technology has contributed to its improved properties. As a result, agricultural nets are widely adopted in large-scale farming applications, for example, in cereal crop farming. However, a consequence of this increased use of agricultural nets is the accumulation of large amounts of waste. The current paper focuses on the recycling of agricultural nets used in wrapping straw bales to develop additives and fillers in cement composites. The research details an analysis of the use of waste agricultural meshes as an ingredient in cement composites. Six test series of different mixtures were conducted. In the first four series, agricultural waste was utilised as an additive in a composite comprising aggregate and cement slurry (the amounts of wasted nets were 20, 40, 60, and 80 kg/m3). In the last test series, the recyclate utilised comprised a mixture of cement slurry and waste only. The composites were subjected to standard tests and thermal resistance tests. The results showcased that that the addition of a net worsened the workability of the concrete mixture, and with increasing amounts of addition, the consistency of the mixture could change from liquid to dense plastic. The flexural strength of the composite decreased with increasing amounts of recyclate. In subsequent test series, the flexural strength value was lower than that of the control (3.93 MPa), from 7.38% (3.64 MPa) for the composite with 20 kg/m3 of recyclate to 37.66% (2.45 MPa) for the composite with of 80 kg/m3 recyclate. The flexural strength value of the net-filled composite without aggregate was very high (10.44 MPa), where the value obtained for the control composite was 62.36% lower. The results of the compressive strength test showed a decrease in this parameter with increasing amounts of additive. The value assessed for the control composite was 27.99 MPa. As expected, the composite that had no aggregate and consisted of only recycled filler had the lowest compressive strength. The value of this parameter was 13.07 MPa, and it was 53.31% lower than that of the control composite. The results of the tests of resistance to temperatures were similar to those recorded for the composites with polypropylene fibres. All composites demonstrated a significant decrease in their compressive and flexural strength after annealing. SEM imaging showed that the net fibres were closely bonded to the cement stone. Finally, it was concluded that recyclates performed best as fillers in lightweight composites with a low density, low absorption, high flexural strength, and satisfactory compressive strength. [ABSTRACT FROM AUTHOR]

Polyethylene-, polyvinylidene chloride-, and per- and polyfluoroalkyl substance-coated paper generate microplastics or fluorochemicals in the environment. Here, we report an approach for the development of oil-resistant papers using an environmentally friendly, fluorine-free, water-dispersible poly(dimethylsiloxane) (PDMS) coating on kraft paper. Carboxylic-functionalized PDMS (PDMS-COOH) was synthesized and subsequently neutralized with ammonium bicarbonate to obtain a waterborne emulsion, which was then coated onto kraft paper. The water resistance of the coated paper was determined via Cobb60 measurements. The Cobb60 value was reduced to 2.70 ± 0.14 g/m2 as compared to 87.6 ± 5.1 g/m2 for uncoated paper, suggesting a remarkable improvement in water resistance. Similarly, oil resistance was found to be 12/12 on the kit test scale versus 0/12 for uncoated paper. In addition, the coated paper retained 70–90% of its inherent mechanical properties, and more importantly, the coated paper was recycled via pulp recovery using a standard protocol with a 91.1% yield. [ABSTRACT FROM AUTHOR]

In the process of paper recycling, certain amounts of metals can be found in the cellulose suspension, the source of which is mainly printing inks. The paper industry often uses different technologies to reduce heavy metal emissions. The recycling of laminated packaging contributes to the formation of sticky particles, which affects the concentration of heavy metals. This study aimed to determine the mass fraction of metals in the different phases of the deinking process to optimize the cellulose pulp's quality and design healthy correct packaging products. In this research, the deinking flotation of laminated and non-laminated samples was carried out by the Ingede 11 method. As a result of the study, the mass fractions of metals in cellulose pulp were divided into four groups according to the mass fraction's increasing value and the metals' increasing electronegativity. The quantities of metals were analyzed using Inductively Coupled Mass Spectrometry (ICP-MS). The separation of metals from cellulose pulp is influenced by the presence of adhesives and the electronegativity of the metal. The results of the study show that the recycling process removes certain heavy metals very well, which indicates the good recycling potential of pharmaceutical cardboard samples. [ABSTRACT FROM AUTHOR]

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually results in models that are inconvenient to implement and/or interpret. In this paper, a comprehensive study of several machine learning methods for the prediction of flotation deinking performance is carried out, including support vector regression, regression tree ensembles (random forests and boosting) and Gaussian process regression. The prediction relies on the development of a limited dataset that assumes representative data samples obtained under a variety of laboratory conditions, including different reagents, pH values and flotation residence times. The results obtained in this paper confirm that the machine learning methods enable the accurate prediction of flotation deinking performance even when the dataset used for training the model is limited, thus enabling the determination of optimal conditions for the paper recycling process, with only minimal costs and effort. Considering the low complexity of the Gaussian process regression compared to the aforementioned ensemble models, it should be emphasized that the Gaussian process regression gave the best performance in estimating fiber recovery (R2 = 97.77%) and a reasonable performance in estimating the toner recovery (R2 = 86.31%).

Deinking waste paper is done in various ways, and research on newer methods is also being done. Traditional deinking methods to remove ink from waste printing papers have a relatively high efficiency compared to contact methods, but in non-contact printing such as electrophotographic printing (LaserJet printers and photocopiers) due to Mixing of the ink with the paper texture during the stabilization of the ink with the help of high heat, the traditional deinking methods are less efficient and it is necessary to use newer methods. In this research, enzymatic deinking of office waste paper was done by a commercial cellulase enzyme in a neutral environment. 15 tests were conducted, and optical and printing properties including the paper were investigated. By measuring the reflection before and after printing and measuring the print density after printing, it was determined that the printability of deinked paper is within the desired range. Eric's number was 128 ppm for sample number 8 and 138 ppm for sample number 12, which has decreased compared to the control sample with an Eric number of 571 ppm. Measuring the reflection before and after printing and measuring the print density after printing, show that the printability of decomposed ink paper is in the desired range. [ABSTRACT FROM AUTHOR]

Carbon containing waste has a certain calorific value and utilization value due to the presence of carbon elements. However, the current treatment methods are mostly traditional landfill disposal, incineration, or expensive physical and chemical reaction methods, which clearly do not comply with the rules of the current clean and resource-saving society. In this paper, a new technology and system for carbon containing wastes is proposed, which comprehensively treats and recycles carbon containing wastes, including solid waste, wastewater, waste gas, etc., using pyrolysis–gasification two-stage-cycle technology. The calculation results indicate that the technical scheme proposed in this article is feasible and can achieve the recycling of intermediate and final products, the efficient and clean utilization of carbon containing waste, and the graded utilization of energy. The clean utilization rate of carbon containing waste can be effectively improved, the energy consumption and cost of separate treatments can be reduced, and zero waste emissions can be completely achieved by the comprehensive pyrolysis–gasification two-stage-cycle treatment and resource utilization technology, which is one of the preferred solutions for future resource-saving societies. [ABSTRACT FROM AUTHOR]

This study focuses on the increased risk of high heat release and asphyxiation (toxic gas poisoning) in the event of a fire involving polyurethane (PU)- and MDF-based building materials, which are commonly used in buildings. Among them, polyurethane (PU) building materials are very commonly used in buildings, except in Europe and some other countries, due to their excellent thermal insulation performance. Still, problems of short-term heat release and the spread of toxic gases in the event of a fire continue to occur. To overcome these problems, researchers are actively working on introducing various flame retardants into building materials. Therefore, in this study, we produced a laboratory-sized (500 mm × 500 mm) plate-like flame-retardant board that can be utilized as a building material with a lower heat release rate and a lower toxicity index. The material was made by mixing expanded graphite and ceramic binder as flame retardants in a material that is formulated based on the cellulose of waste paper, replacing the existing building materials with a hot-press method. According to the ISO-5660-1 test on the heat release rate of the plate-like flame-retardant board, the Total Heat Release (THR) value was 2.9 (MJ/m2) for 10 min, showing an effect of reducing the THR value by 36.3 (MJ/m2) compared to the THR value of 39.2 (MJ/m2) of the specimen made using only paper. In addition, the toxicity index of the flame-retardant board was checked through the NES (Naval Engineering Standards)-713 test. As a result, the test specimen showed a toxicity index of 0.7, which is 2.4 lower than the toxicity index of 3.1 of MDF, which is utilized as a conventional building material. Based on the results of this study, the cellulose fire-retardant board showed the effect of reducing the heat release rate and toxicity index of building materials in a building fire, which reduces the risk of rapid heat spread and smoke toxicity. This has the potential to improve the evacuation time (A-SET) of evacuees in fires. It is also important to show that recycling waste paper and utilizing it as the main material for building materials can be an alternative in terms of sustainable development. [ABSTRACT FROM AUTHOR]

This research explores the challenges and limitations faced at the basic level for the recycling of paper in an academic institute. It focuses on encouraging recycled paper use rather than bringing traditional virgin paper to prevent the rate of deforestation for reducing global warming. Data was collected from the academic institute via questionnaire and on-site observation and found that the institute was producing approximately 16 tons of wastepaper in a year. Besides that, another purpose of this research is to estimate the energy and assess the environmental effect by using the life cycle assessment as a tool. The results of this study revealed that traditional virgin paper derived from wood proves to be costly and less environmentally friendly than recycled paper. It also revealed that Traditional virgin paper has greater global warming, human toxicity, smog, acidification, and eutrophication potential than recycled paper. This study concludes that recycled paper does not only prove economically beneficent for any institution, but also beneficial for environment as well. [ABSTRACT FROM AUTHOR]

Special effects on a printed product can increase consumer's interest in a product and therefore lead to higher revenues in consumer industries. For that purpose, graphic industry introduced various technologies and materials that would have such an effect and enhance consumer-goods interaction. One of those solutions is thermochromic printing. Although bringing added value, thermochromic inks have some challenges in application due to their higher sensitivity, especially when exposed to UV light. Therefore, the goal of this work is to determine whether amount of the UV radiation during curing of UV thermochromic prints, as well as exposure after printing would degrade the thermochromic print on various substrates. UV thermochromic prints were made on three different paper printing substrates using the screen printing method and dried in a laboratory controlled unit. Synthetic paper, recycled paper containing 100 % recycled cellulose fibers and bulky voluminous paper were used as printing substrates. During the UV curing of the ink, no photooxidation of the prints occurred. Additional exposure of the prints to UV radiation (after the ink has hardened) leads to their photooxidative degradation, i.e., a change in the initial color. The obtained colour difference (ΔE) is increasing with the increase of the irradiation amount. The highest colour difference is on the synthetic paper while prints on two other substrates are more resistant to UV light. A print on synthetic paper photooxidizes the fastest due to the presence of most carbonyl groups in it. Generated free radicals promote the instability of prints on synthetic paper. Research has proven that when using synthetic paper or substrates with similar characteristics, care should be taken to accurately determine the amount of UV energy required for curing in order to prevent photodegradation of the ink. The results also show that to explain any degradation of prints, the chemical components of the paper needs to be taken into account, which is rarely done. [ABSTRACT FROM AUTHOR]

Background and objectives: Waste paper recycling utilization has been increasing in Iran and world paper industries which offers many benefits to the environment and humans. Municipal waste is also reused after recycling processes. Cardboard recycling industry has great environmental and economic importance and helps overcone the lack of wood resources and high demand for paper products. It plays an important role in the development of paper-related industries. However, recycling can be associated with the reduction in the optical properties of the paper. The use of nanoparticles in the paper industry is also expanding gradually. Nanosilica is one of the most important nanoparticles which is used as a retention aid in the paper industry. In order to reduce the consumption of long fibers and obtain the desired optical properties, the use of nanosilica alone or in combination with other materials such as cationic starch and cationic polyacrylamide is investigated. The purpose of this research is to compare the effect of individual and combined use of nanosilica additives, cationic polyacrylamide, cationic starch and long fibers on the optical properties of white liner paper pulp. Methodology: In this study, white paper pulp with the brightness of at least 78% and the gloss of at least 45% was used to prepare handmade paper sheets. Long fiber kraft chemical pulp from coniferous wood imported from Russia with the brightness of 89% was used in the laboratory paper sheet making. Nanosilica powder (NanoSiO2) (Degussa), Germany, cationic polyacrylamide (Farinret K325 brand, Degussa, Germany), and cationic starch (LyckebyAmylex, Slovakia) were used. Independent treatments included the addition of 10% refined long fibers pulp, 6% nanosilica, 1.5% cationic starch and 0.15% cationic polyacrylamide and combined treatments included 6% nanosilica and 1.5% cationic starch and 6% nanosilica and 0.15% cationic polyacrylamide. Then 127 g.m-2 handmade papers were prepared and the optical and microscopic properties were evaluated. Results: The results showed that by adding 10% long fibers, the brightness decreased and by using 6% nanosilica, the maximum brightness was reached. Meanwhile, the whiteness of papers with 6% nanosilica was minimum and with the dosage of only 0.15% cationic polyacrylamide, the whiteness reached at the maximum value. Opacity showed its highest value with the combination of 6% nanosilica and 0.15% cationic polyacrylamide. Also, by increasing the amount of polyacrylamide and cationic starch, individually or in combination with nanosilica, the opacity increased. The light absorption coefficient was the lowest in papers with 6% nanosilica and the light scattering coefficient was the highest in papers containing 6% nanosilica and 0.15% cationic polyacrylamide. A colorimeter was used to measure the color components and the results showed that the additives had an effect on the brightness and whiteness of the papers. Also, changes in the color spectrum and the value of color change were also observed. Additives increased the darkness and changes in different colors. Conclusion: The use of nanosilica individually and in combination with starch and cationic polyacrylamide increases the brightness of papers. Also, the use of cationic polyacrylamide individually and in combination with nanosilica leads to an increase in the whiteness and opacity of papers. The brightness factor of the papers, which is representative of the L* component, decreased with the exception of the addition of 10% long fibers and 6% nanosilica. The amount of overall color change with ΔE* was the lowest in samples containing 1.5% cationic starch and the highest in samples containing 0.15% cationic polyacrylamide. The use of some treatments can lead to a decrease in the optical properties and a decrease in the printability quality of the white liner. To solve this problem, mechanical pulp that has been decolorized or coated on the surface of the paper can be used. The presence of nano-silica particles in the structure of the paper improves the surface structure and reduces the prosity, which results in the reduction of surface roughness and less light refraction, and increases the light reflection and brightness of the paper. [ABSTRACT FROM AUTHOR]

Background and objectives: Paper industry in addition to reducing the consumption of various resources such as water, energy, and wood, continues to recycle used paper in different countries due to less pollution. One of the major drawbacks of the old corrugated container (OCC) recycling is its relatively weak strength, which has limited its use in various sections of the packaging industry. In this study, the effect of using some additives to improve the strengths of OCC to make the top liner of cartons in both wet and dry conditions was studied. Methodology: OCC was selected from domestically produced cartons. To determine the performance and optimal amount of additives, corn cationic starch (at 1, 1.4 and, 2%), wet strength resin (at 1, 2 and, 3%), AKD (at 1, 2 and, 3%), and long fiber of imported bulk tea wrapping paper (at 10, 15 and, 20%) based on the dry weight of OCC pulp were separately used as additives. The handsheets were made using laboratory sheet former with the basis weight of 120 g/m² and then tensile, burst, and tear indices were measured both at wet and dry conditions to compare the effect of additives. Also, water absorption was measured by the Cobb test on the test samples. The optimal level of each additive was determined based on the results, and then handsheets data from optimal combination treatment including appropriate levels of all additives, and different properties of handsheets were statistically compared. Results: The water absorption of handsheet was statistically decreased to 90% level compared to the control by adding AKD. This additive was able to reduce the water absorption of handsheet made from OCC to about 20 g/m² as the appropriate range. The greatest increase of wet tensile strength of the handsheet was achieved using 3% wet strength resin compared to the control. The resin maintained the wet tensile, burst, and tear indices of the residual strength of handsheet by 25, 46, and 58%, respectively, compared to dry strengths which indicates its good performance. The results showed that by adding cationic corn starch and recycled long fiber paper, all the dry strengths of handsheet independently increased compared to the control. The optimal combination treatment was determined according to the results independent use of additives in OCC pulp, including 1% cationic starch, 1% AKD, and 3% wet strength resin based on technical-economic considerations. There is no significant difference between dry tensile and burst strength of handsheet using this treatment and 20% recycled long fiber of wrapping paper, which both means ranked statistically in the same group. Conclusion: The use of 20% recycled long fiber of wrapping paper significantly improved the dry strength of OCC pulp, but adding 1% cationic corn starch to OCC pulp caused limit increase in dry strength. The wet strength of handsheet was significantly improved by adding 3% wet strength resin whereas 1% AKD significantly decreased the water absorption of the OCC pulp to 14 g/m². The optimal combination treatment of chemical additives including 1% cationic corn starch, 1% AKD, and 3% wet strength resin improved the wet and dry strength of handsheet made from OCC pulp that could be used for packaging products which need to be kept in refrigerator and freezer. [ABSTRACT FROM AUTHOR]

The pulp and paper industry plays an important role in the global economy and is inextricably linked to human life. Due to its large scale, the production process generates a large amount of wastewater, which poses a major threat to the environment. The sustainable utilization and safe treatment of pulp and paper wastewater can effectively reduce environmental pollution, improve resource utilization efficiency, protect water resources, provide economic benefits for pulp and paper enterprises, and thus promote the green and sustainable development of the pulp and paper industry. Therefore, this study discusses the pollution components of pulp and paper wastewater and their impact on the environment and human health. In this review, we aim to explore the sustainable development of pulp and paper wastewater by summarizing the characteristics of current pulp and paper wastewater, the commonly used treatment methods for pulp and paper wastewater, the application of pulp and paper wastewater recycling, and the future development direction of pulp and paper wastewater. [ABSTRACT FROM AUTHOR]

Finding eco-friendly products that are beneficial to the environment and serve as tools for sustainable development is a contemporary challenge. This work illustrates the recovery of bio-waste-based materials, which not only improve the hygrothermal properties of gypsum but also promote the paper and wood recycling processes in a circular economy approach. The samples were subjected to tests for density, water absorption, ultrasonic pulse velocity, flexural strength, compressive strength, and thermophysical property characterization. A statistical analysis of variance was used to study the impact of waste on the physico-mechanical behavior of gypsum, leading to the development of predictive models that can be used to predict and optimize the performance of bio-composites in various applications. The results revealed a reduction in mechanical strength with the addition of waste, but the samples still exhibit superior insulation properties, surpassing commonly used standard boards. By adding ouate and wood wastes to a mass of 20% in its natural state, the gypsum becomes lighter and acts as a better insulator with a reduced density, thermal conductivity, and ultrasound velocity of up to 50%, 57%, and 83%, respectively. These findings show the significant implication of reducing environmental impacts while contributing to the promotion of sustainable building practices, both in new construction projects and in building renovations. [ABSTRACT FROM AUTHOR]

To ensure development sustainability, the linear economic approach is being transformed into a cyclical model. For the pulp and paper industry (PPI), which occupies a significant place in the Russian economy, the shift of circular principles to the field of bioeconomics is becoming more important. This requires the development of basic biotechnological approaches implemented in closed cycles (biorefining). The aim of this study was to develop the biotechnological foundations of the circular economic system of the pulp and paper industry. To achieve the goal, the factors for the implementation of the circular mechanism in the pulp and paper industry were established. The composition of pulp and paper waste was systematized, taking into account the places of their occurrence; the directions and forms of the biorefining of pulp and paper secondary renewable resources were determined; and the principal possibility of obtaining bioethanol, based on the whole complex of sugars from cellulose production wastes, is shown. A wide range of general scientific methods was involved (analysis, synthesis, classification, modeling, etc.). Statistical methods were used to process experimental results in the field of pulp and paper waste bioconversion. The biotechnologies involved included methods of destruction, detoxification, and conversion of useful resources into secondary raw materials and final products. From the standpoint of the environmental approach, there are serious efficiency imbalances in the pulp and paper industry, which justify the implementation of circular mechanisms for organizing economic systems. The overall efficiency is ensured by the use of renewable resources and obtaining environmental effects. Algorithms and parameters of green biotechnological regulations for pulp and paper industry waste recycling provide the possibility of microbiological production of a complex of products: biocomposites, bioplastics, medical products, fertilizers, feed additives, vitamin supplements, and bioenergy resources. A strategy for the efficient biochemical processing of pulp and paper waste into green ethanol was determined. The possibility of increasing the efficiency of alcoholic fermentation using various biocatalysts was experimentally confirmed. The technological features of this method, associated with the need for microaerobic fermentation modes, were determined. [ABSTRACT FROM AUTHOR]

In this study, we conducted a novel method by using a household type Microwave Owen (MW) under selected operational parameters (power and time) to treat wastewater from paper recycling under laboratory conditions. We seek to evaluate changes of the MW experimental parameters, comparatively. All measured pH values were found to be in very narrow range, between pH 7.10 (BII) and pH 7.53 (DIV), in slightly alkaline range (>7.0). However, the highest Electrical Conductivity (EC) difference was found to be 46 µS/cm. The 60 seconds MW irradiated samples at four power levels (90-, 180-, 270-, 360 Watts) showed higher ORP values than control (C1: 195 mV) while the highest ORP value of 213 mV was found with sample treated 360 W and 60 seconds (DIV). It is notable that sample DIV showed the highest pH, EC, ORP and TDS value. The control sample had turbidity value of 42.5 NTU. In all MW power levels and durations, turbidity removal was apparent which MW impact on turbidity. The lowest turbidity value of 22.2 NTU was found with sample DIV which was the highest rate of turbidity removal efficiency (DIV: 86.2%). The present study revealed that MW irradiation could be used to effectively reduce the selected physicochemical parameters that may assist in the description of wastewater quality.

The leather sector is currently under heavy threat to reduce environmental pollution problems associated with the generation of leather waste, especially in terms of public acceptance issues related to environmental welfare requirements. Leather waste must be disposed of in landfills, which has a significant environmental impact. The development of natural polymer/paper mill sludge-based leather replacements for the production of leather goods and footwear products is an alternative solution supported by the recycled leather industry. In this work, a study is carried out to prepare natural polymer leather sheet (NPLS) from leather waste (chrome shavings and buffing dust), paper mill sludge, and natural polymer [natural rubber latex (NRL)] by vacuum-pressure method, for their potential application in leather products industries. The NPLS was characterized by its physicochemical and mechanical properties. Various types of NPLS were produced by comprising different ratios of the NRL. Results portrayed that 300 mL w/v NRL significantly improved the physicochemical and mechanical properties of NPLS. Hence, the research has revealed a revolutionary idea of NPLS developed which is cost-effective, eco-friendly, and energy efficient. [ABSTRACT FROM AUTHOR]

In this study, Al paper and cellulose acetate (CA) filters derived from heated tobacco waste were successfully converted into current collectors and active materials for a supercapacitor device. Typically, heated tobacco contains electrically discontinuous Al paper. First, Al was extracted from the tobacco waste using HCl to produce Lewis acid (AlCl3). This acid was then used in an Al electrodeposition process utilizing the chloroaluminate ionic liquid reaction between the acid and the base (RCl) at room temperature. To enhance the conductivity, a supplementary coating of Al metal was applied to the Al paper through electrodeposition, thus re-establishing the electrical continuity of the discontinuous parts and forming an Al-coated current collector. Moreover, the CA filters were carbonized under a nitrogen atmosphere, yielding carbon precursors (C-CA) for the supercapacitor electrodes. To further enhance the electrochemical performance, nickel oxide (NiO) was incorporated into C-CA, resulting in C-CA@NiO with pseudocapacitance. The specific surface area of CA increased with carbonization and the subsequent incorporation of NiO. The as-synthesized C-CA and C-CA@NiO materials were applied to an Al-coated current collector to obtain C-CA- and C-CA@NiO-based electrodes, exhibiting stable electrochemical behavior in the voltage range of −1.0 to 0 V and 0 to 1.0 V, respectively. An asymmetric supercapacitor (ASC) device was assembled with C-CA@NiO and C-CA as the positive and negative electrodes, respectively. This ASC device demonstrated a high specific capacitance of 40.8 F g−1, while widening the operating voltage window to 2.0 V. The high electrochemical performance of the device is attributed to the successful Al electrodeposition, which facilitates the electrical conductivity and increased porosity of the C-CA@NiO and C-CA materials. To the best of our knowledge, this is a pioneering study in regards to the conversion of biomass waste into current collectors and active materials to fabricate a practical ASC device. Our findings highlight the potential of reusing Al paper and CA filters from heated tobacco waste as essential components of energy storage devices. [ABSTRACT FROM AUTHOR]

In the cultivation of extensive green roofs (EGRs), substrate composition is a key aspect together with the evaluation of suitable recycled materials. Recycling materials as amendments can improve the establishment of a self-sustainable EGR, thus providing ecosystem services and benefits from a circular economy and climate change perspective. This study investigates the effects of compost and paper sludge on water retention, substrate temperature attenuation and plant diversity in an EGR experiment. The substrates were composed of tephra (V), compost (C) and paper sludge (P) as follows: VC, as control, VPC and VP. Herbaceous species with different ecological functionality (succulents, annuals, perennials, legumes, geophytes) were sown and/or transplanted with no cultivation inputs. Plant community composition -abundance- and diversity-richness-, substrate water retention and temperature were analyzed. The VPC and VC had the same average substrate temperature, with values lower than VP. The water retention capacity was higher in VC, thanks to the presence of compost. The substrate with paper sludge (VPC and VP) showed the highest species diversity. The VPC substrate was the best compromise for EGR temperature mitigation and plant diversity improvement. Plant functional types in EGRs can be increased, and thus the biodiversity, by modulating the quality and percentage of amendments. The substrate composition can also affect water retention and substrate temperature. In addition, the use of recycling paper sludge in growing media is a winning strategy to reduce waste. [ABSTRACT FROM AUTHOR]

As a kind of biomass resource, waste office paper can be used as a carbon precursor to prepare carbon materials. In this work, carbon microspheres with regular shape, uniform particle size and high carbon content were successfully prepared from waste office paper via a hydrothermal synthesis method with sulfuric acid as the catalyst. The effects of reaction temperature and sulfuric acid dosage on the morphology of the carbon microspheres were studied. The formation mechanism of the carbon microspheres was investigated by analyzing the structure and composition of the products. The results show that the hydrolysis of cellulose in waste paper under hydrothermal conditions was the key for the formation of carbon microspheres. The temperature of hydrothermal reaction and the use of sulfuric acid can affect the morphology of carbon microspheres. The carbon microspheres synthesized at 210 °C with 10 mL sulfuric acid have the best surface morphology, with uniform particle size and higher dispersion. Cyclic voltammetry and electrochemical impedance spectroscopy show that the carbon microspheres have good capacitance performance and can be used in capacitors. This study provides a low-cost precursor for carbon microspheres as well as a new method for the recycle of waste paper. [ABSTRACT FROM AUTHOR]

The authors used time-series data from 1975 to 2020 on combustible renewables and waste production and recycling. References 1 Ben Yahya T., Jamal N.M., Sundarakani B., Omain S.Z. The Effects of Data Security and Perceived Benefits on Mobile Phone Recycling Behaviour and the Recycling Intention Mediation Role. This Special Issue aimed to collect high-quality papers (original research articles or comprehensive review papers) published during 2022 on the subject of waste recycling. Waste Management Analyses Efficient waste management systems are crucial in order to match the high recycling goals set by European Union by 2030. [Extracted from the article]

The active mass of the plates of aspent car battery with higher wear after an efficient desulfatization can be used as sources of a new electrode. This paper proposes the recycling of spent electrodes from a lead acid battery and the incorporation of NiO or Co3O4 contents by the melt-quenching method in order to enrich the electrochemical properties. The analysis of X-ray diffractograms indicates the gradual decrease in the sulfated crystalline phases, respectively, 4PbO·PbSO4 and PbO·PbSO4 phases, until their disappearance for higher dopant concentrations. Infrared (IR) spectra show a decreasing trend in the intensity of the bands corresponding to the sulfate ions and a conversion of [PbO3] pyramidal units into [PbO4] tetrahedral units by doping with high dopant levels, yielding to the apparition of the PbO2 crystalline phase. The observed electron paramagnetic resonance (EPR) spectra confirm three signals located on the gyromagnetic factor, g~2, 2.2 and 8 assigned to the nickel ions in higher oxidation states as well as the metallic nickel nanoparticles. This compositional evolution can be explained by considering a process of the drastic reduction in nickel ions from the superior oxidation states to metallic nickel. The linewidth and the intensity of the resonance lines situated at about g~2, 2.17, 4.22 and 7.8 are attributed to the Co+2 ions from the EPR data. The best reversibility of the cyclic voltammograms was highlighted for the samples with x = 10 mol% of NiO and 15 mol% of Co3O4, which are recommended as suitable in applications as new electrodes for the lead acid battery. [ABSTRACT FROM AUTHOR]

Fiber-reinforced thermoplastics are an important construction material for lightweight applications. The increasing use of especially glass fiber-reinforced plastics leads to growing amounts of not recyclable composite materials, which is commonly disposed of by landfilling. Hence, there is a need for a recycling concept for glass-fiber-reinforced plastics that enables their complete reuse over many recycling cycles. In this paper, such a recycling concept is presented, which is based on the idea of melting the whole glass-fiber-reinforced component without prior size reduction. The fiber-reinforced melt will be pressed through a nozzle in order to achieve a strand with highly oriented fibers that can then be applied in new components via a tape-like laying process. The feasibility of the recycling concept is proved in this paper. Therefore, investigations on the reorientation of fibers in the melt by pressing through a rectangular nozzle have been carried out with different nozzle diameters, shear rates and melt temperatures. The investigations result in a stable process, which enables an increase in fiber orientation of about 37% up to a mean fiber orientation of 67% in the flow direction. These findings are independent of the initial fiber orientation. [ABSTRACT FROM AUTHOR]

This paper defines terms such as "recycling rate" that enable the characterization of flows of battery materials and expands the terminology to accommodate the description of complex product recycling. It also estimates the maximum percentage of U.S. demand for critical elements that could be satisfied by recycling as demand continues to grow, and it defines and estimates the recycling rate for lithium-ion batteries. Finally, it clarifies the role of manufacturing scrap as the domestic U.S. supply chain is built up. It concludes that recycling will be important in the long term, but growth still requires that new material be extracted to supply additional material. [ABSTRACT FROM AUTHOR]

Sticky contaminants present one of the biggest technical challenges in the paper recycling process. These contaminants reduce paper strength, cause plugging of wires and felts, and stick to or deposit on machine parts affecting the runnability of the paper machine. In this study, first, the sticky deposit on doctor blades was subjected to multi-stage extraction with alcohol, acetone, toluene, and tetrahydrofuran solvents respectively. Then the nature of the resulting material and its physicochemical properties was investigated with FTIR analysis, GC-MS, TGA, XRF, SEM. The results showed that these deposite originates from the fibers, polymers such as polyvinyl acetate and styrene butadiene, which are components of hot melt adhesives, and fatty acid/resin esters. Fatty acids and resins are the most common organic compounds in stickies deposite. The possible origin of these compounds are chemical substances (saponified fatty acids), deinking steps and some resins and fatty acids used in the formulation of adhesives or more resistant resins and extractive materials related to cellulosic fibers. The identified minerals are mainly calcium, iron, silica and aluminum, which are present in the formulation of fillers and coating pigments during the papermaking process. [ABSTRACT FROM AUTHOR]

The emission of off-odors from mechanically recycled plastics severely limits their re-introduction into the market for the production of new objects, for the same use or even for less demanding applications, thus hindering the implementation of an effective circular economy for plastics. The addition of adsorbing agents during the extrusion of polymers represents one of the most promising strategy to reduce the odorous emissions of plastics, due to its characteristics of cost-effectiveness, flexibility and low energy consumption. The novelty of this work lies in the assessment of zeolites as VOC adsorbents during the extrusion of recycled plastics. They appear more suitable than other types of adsorbents, due to their ability to capture and "hold" the adsorbed substances at the high temperatures of the extrusion process. Moreover, the effectiveness of this deodorization strategy was compared with the traditional degassing technique. Two types of mixed polyolefin wastes, coming from completely different collection and recycling processes, were tested: Fil-S (Film-Small), deriving from post-consumer flexible films of small size, and PW (pulper waste), which is the residual plastic waste obtained from the paper recycling process. The melt compounding of the recycled materials with two micrometric zeolites (zeolite 13X and Z310) resulted as more effective in the off-odors removal with respect to degassing. In particular, the highest reduction (−45%) of the Average Odor Intensity (AOI) was measured for both PW/Z310 and Fil-S/13X systems at 4 wt% of the zeolites' amount, compared with the corresponding untreated recyclates. Finally, by combining degassing and melt compounding with zeolites, the best result was obtained for the composite Fil-S/13X, whose Average Odor Intensity resulted as quite close (+22%) to the one of the virgin LDPE. [ABSTRACT FROM AUTHOR]

Recycled fibers are essential raw materials used by the paper industry. However, the strength of the formed paper may fall off excessively after several cycles of reuse of the fibers. Herein, the authors measured the changes in physical properties and fiber size after multiple recycling of fibers and prepared a handsheet from fiber recycled different times. Then the handsheets made with fibers that had been recycled 5 times were double-coated with nanocellulose derivatives to obtain oleophobic and hydrophobic paper. The first layer applied to the paper was cellulose nanofibril (CNF), and the second coating contained polydimethylsiloxane (PDMS) and CNF (CNFmp). The physical properties and barrier performance of coated paper were greatly improved compared to recycling paper. The water contact angle of the coated paper was as high as 139.8° and the Cobb60 value was 35.18±2.15 g/m2. The oil contact angle was 97.1°, and the oil kit number was 12/12. [ABSTRACT FROM AUTHOR]

In the past decades, the German paper industry has been increasing the sustainability of paper production by continuously using more recovered paper. Today, recovered paper is an essential secondary raw material to produce new paper. Nevertheless, around 20 % of the paper produced in Germany is still not returned to the recovered paper stream and instead is mostly thermally used. To further increase the use of fibers from recovered paper as secondary raw material and thus, to reduce primary energy consumption and greenhouse gas emissions, new approaches to recycle recovered paper from mixed waste streams are needed. In the research project "Energy savings in paper production by opening up the value chains of recovered paper from lightweight packaging, residual waste and commercial waste" (EnEWA), a treatment process is developed to recover and recycle recovered paper from the mentioned waste streams. The advanced mechanical process to be newly developed consists of dry-mechanical sorting, the manufacturing of economically usable secondary raw materials (defibration), their wet-mechanical dissolution, separation and hygienization and finally their reuse in paper production. This enables the exploitation of new waste streams in material recycling and thus contributes to reduced energy consumption as well as CO2 emissions within the circular economy. Initial material characterization analyses show that on the one hand the quality of the paper discarded in mixed waste streams is sufficient to be used as secondary raw material and that on the other hand up to 50 % of the paper discarded could have been disposed of within the separate paper collection. The results are incorporated in the development of a sorting process for pre-concentrates, which serves as input material for the treatment process to recover paper fibers. In further steps, the results generated will be integrated, for instance, into the future development of the minimum standard for packaging recycling. [ABSTRACT FROM AUTHOR]

Recycling is emerging as both a viable alternative to extraction in many industries and a cornerstone of the circular economy. In this paper, we assess the role of paper and cardboard recycling on the forest sector, from both an economic and carbon perspective. For this purpose, we add the recycling industry to an existing forest-sector model in an attempt to capture its effects on other wood products and the overall forest resource. As the forest sector has an important potential for climate change mitigation, this model allows us to assess the effects of increased paper and cardboard recycling on the availability of the natural resource and the carbon balance of the forest sector. We show that these results are strongly linked to the hypotheses of substitutability and/or complementarity of recycled pulp and virgin pulpwood. Although we find increased emissions at the pulp sector level, the effects on emissions in other wood products are small. When pulp products are considered substitutes, we find the impact on total net sequestration to be positive. In the case where pulp products are considered complements, we find the impact on total net sequestration to be negative. [ABSTRACT FROM AUTHOR]

The purpose of this research is to study the changes in the market structure of China's pulp and paper product imports. In particular, the import trade environment and market layout of Chinese pulp and paper products have changed under the international context of the coronavirus pandemic and the Sino-US trade dispute and the domestic policy context of zero imports of Chinese waste paper. This study attempts to fill the gap regarding the influencing factors of market structure, while contributing new ideas on China's trade in pulp and paper products. Based on pulp and paper product import and export trade data from 2005 to 2021, a trade gravity model was used to explore the changes in the share of China's trade partners for pulp and paper product imports and their influencing factors. The results indicated that the outbreak of COVID-19 led to a significant increase in China's imports of packaging paper products, bringing about an increase in Indonesia's status as a partner in China's pulp and paper product trade. The US-China trade dispute had an impact on pulp and paper product trade between the two countries, with China's tax countermeasures causing the US to lose its status as a trading partner in China for pulp and paper product imports. The center of gravity for paper product imports has moved from the US and Japan to Indonesia and Russia. The restrictions on waste paper imports have shifted the focus of China's paper raw material imports, with the US no longer being the main importer of China's paper raw materials. Specifically, the main importers of wood pulp are Brazil and Chile, while the main importers of waste paper pulp are Thailand and Malaysia. In the future, China needs to continuously strengthen dialogue with the United States to resolve trade disputes and create a favorable environment for trade in pulp and paper products. At the same time, China's paper enterprises should strengthen the expansion of the Southeast Asian market and reduce dependence on the US market, and China should continue to improve the waste paper recycling system and improve the utilization rate of domestic waste paper. [ABSTRACT FROM AUTHOR]