Abstract The present work was based on analysis of the flow regime of fibre suspensions, that corresponds to furnishes and process conditions typically established for tissue paper manufacturing, i.e., under the common range of stock consistencies at the machine headbox and most usual furnish compositions. The flocculation potential of fibre suspensions used for toilet papers, facial tissues, paper towels and table napkins were evaluated on the principles of analytical concepts for fibre agglomeration propensity. The results show crowding numbers from 5.0 to 69.0, depending on the type of fibre or fibre blending ratios. The findings regarding agglomeration factors indicate that flow regimes are mainly in semi-concentrated and around gel state zones but reached the concentrated flow regime, in extreme conditions of fibre morphology and stock consistency. The influence of hardwood and softwood mixture ratios on the fibre suspension features is shown and discussed for common formulations of tissue base paper. The effect of fibre length and coarseness on the flocculation potential and the impacts of fibre suspension flow regimes on the structural properties of tissue paper, such as the formation uniformity are discussed, demonstrating the reasons for the preferred use of high hardwood content in furnish balance for tissue paper manufacturing.
{"title":"The influence of fibrous suspension flow regimes on the formation of tissue paper manufactured from different furnish compositions","authors":"Afonso H. T. Mendes, Song W. Park","doi":"10.1515/npprj-2023-0011","DOIUrl":"https://doi.org/10.1515/npprj-2023-0011","url":null,"abstract":"Abstract The present work was based on analysis of the flow regime of fibre suspensions, that corresponds to furnishes and process conditions typically established for tissue paper manufacturing, i.e., under the common range of stock consistencies at the machine headbox and most usual furnish compositions. The flocculation potential of fibre suspensions used for toilet papers, facial tissues, paper towels and table napkins were evaluated on the principles of analytical concepts for fibre agglomeration propensity. The results show crowding numbers from 5.0 to 69.0, depending on the type of fibre or fibre blending ratios. The findings regarding agglomeration factors indicate that flow regimes are mainly in semi-concentrated and around gel state zones but reached the concentrated flow regime, in extreme conditions of fibre morphology and stock consistency. The influence of hardwood and softwood mixture ratios on the fibre suspension features is shown and discussed for common formulations of tissue base paper. The effect of fibre length and coarseness on the flocculation potential and the impacts of fibre suspension flow regimes on the structural properties of tissue paper, such as the formation uniformity are discussed, demonstrating the reasons for the preferred use of high hardwood content in furnish balance for tissue paper manufacturing.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"253 - 260"},"PeriodicalIF":1.2,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48316020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Waste paper, the use of which is increasing day by day as a raw material, has a heterogeneous structure as it contains non-fiber material from different sources. It is desired to have a homogeneous product when recycled. Within the scope of this study, the SEM images of the raw materials determined according to EN 643 standard and the products made with the recycling of these raw materials were examined, ash content, fines content and ash on sieve were stated and the results obtained by determining filler content (removed) and fiber fines (removed) were discussed. While the samples with the highest ash content were H3 and U3, the lowest samples were H6 and U9. It was determined that the samples with the highest fines content were H2 and U1, while the lowest samples were H4 and U2. While the samples with the highest ash on sieve were H3 and U3, the samples with the least were determined as H2 and U9. The filler content was highest in H1 and U3 samples, while the lowest was in H6 and U9 samples. The samples with the most fiber fines were found as H2 and U9, and the least as H1 and U3 samples.
{"title":"Determination of fines in recycled paper","authors":"Gulnur Mertoglu Elmas, Beyza Karabulut","doi":"10.1515/npprj-2022-0096","DOIUrl":"https://doi.org/10.1515/npprj-2022-0096","url":null,"abstract":"Abstract Waste paper, the use of which is increasing day by day as a raw material, has a heterogeneous structure as it contains non-fiber material from different sources. It is desired to have a homogeneous product when recycled. Within the scope of this study, the SEM images of the raw materials determined according to EN 643 standard and the products made with the recycling of these raw materials were examined, ash content, fines content and ash on sieve were stated and the results obtained by determining filler content (removed) and fiber fines (removed) were discussed. While the samples with the highest ash content were H3 and U3, the lowest samples were H6 and U9. It was determined that the samples with the highest fines content were H2 and U1, while the lowest samples were H4 and U2. While the samples with the highest ash on sieve were H3 and U3, the samples with the least were determined as H2 and U9. The filler content was highest in H1 and U3 samples, while the lowest was in H6 and U9 samples. The samples with the most fiber fines were found as H2 and U9, and the least as H1 and U3 samples.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"311 - 319"},"PeriodicalIF":1.2,"publicationDate":"2023-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48020290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Dukare, K. Sharma, S. Kautkar, Jyoti Dhakane-Lad, Rahul Yadav, Vigneshwaran Nadanathangam, S. Saxena
Abstract Due to discharge of hazardous organochlorine compounds and absorbable organic halogen compounds in the effluent, the pulp and paper industries are trying to alter the bleaching process to limit the use of chlorine compounds and comply with regulatory, environmental, and market demands. With progress in biotechnology, enzyme technologies can effectively pre-treat lignocellulosic biomass in the pulp and paper making process. Usually, these enzymatic processes reduce the environmental impact of traditional pulp and paper-making processes, lower the overall production cost, and enhance product quality. Microbial xylanases are the potential bio-bleaching candidate due to their renewable, mild operating, highly specific, and eco-friendly nature. Xylanase enhances the efficacy of the bleaching process by breaking the β-1, 4-glycosidic backbone of the re-precipitated xylan network and removing the trapped lignin from the pulp fibers. Xylanolytic action positively influences the kappa number, hexenuronic acid, chromophore compounds release, pulp crystallinity, morphology and many other attributes of pulp. The present review comprehensively highlights the microbial xylanolytic system, its mechanism, and its application in pulp bioleaching. With the recent development, the paper delineates the xylanase-aided bleaching effects on pulp, paper, and effluent attributes aimed to reduce bleaching chemical use, AOX formation, and energy use in the pulp refining process.
{"title":"Microbial xylanase aided biobleaching effect on multiple components of lignocelluloses biomass based pulp and paper: a review","authors":"A. Dukare, K. Sharma, S. Kautkar, Jyoti Dhakane-Lad, Rahul Yadav, Vigneshwaran Nadanathangam, S. Saxena","doi":"10.1515/npprj-2023-0005","DOIUrl":"https://doi.org/10.1515/npprj-2023-0005","url":null,"abstract":"Abstract Due to discharge of hazardous organochlorine compounds and absorbable organic halogen compounds in the effluent, the pulp and paper industries are trying to alter the bleaching process to limit the use of chlorine compounds and comply with regulatory, environmental, and market demands. With progress in biotechnology, enzyme technologies can effectively pre-treat lignocellulosic biomass in the pulp and paper making process. Usually, these enzymatic processes reduce the environmental impact of traditional pulp and paper-making processes, lower the overall production cost, and enhance product quality. Microbial xylanases are the potential bio-bleaching candidate due to their renewable, mild operating, highly specific, and eco-friendly nature. Xylanase enhances the efficacy of the bleaching process by breaking the β-1, 4-glycosidic backbone of the re-precipitated xylan network and removing the trapped lignin from the pulp fibers. Xylanolytic action positively influences the kappa number, hexenuronic acid, chromophore compounds release, pulp crystallinity, morphology and many other attributes of pulp. The present review comprehensively highlights the microbial xylanolytic system, its mechanism, and its application in pulp bioleaching. With the recent development, the paper delineates the xylanase-aided bleaching effects on pulp, paper, and effluent attributes aimed to reduce bleaching chemical use, AOX formation, and energy use in the pulp refining process.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"0 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41417506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. G. de Lima, B. Aggio, M. Matos, T. A. M. D. de Lima, B. Pereira, A. C. Pedro, W. L. Magalhães
Abstract Approaches to obtain nanocellulose have been extensively suggested, and among the most competitive methodologies includes mechanical defibrillation, which results in a nanocellulose gel suspension that can be used in a variety of applications. However, standard procedures results in inhomogeneous fibre sizes due to its physical approach. Pre-treatments have been suggested, such as enzymes, but their cost is a disadvantage. In this work, we suggest the use of cryoslash for bleach kraft pulp using a simple methodology of embedding the dry kraft pulp in distilled water following by freezing at −80 °C, which was slashed using a common blender and submitted to an ultra-fine friction grinder. Samples were studied at various grinding steps 5, 15, 30, 60 and 120. Overall, the energy difference required to defibrillate with cryoslash was ∼3.26 kWh/kg at 30 steps and ∼6 at 120 steps, which was similar to enzymatic pre-treatment with nanofibrils significantly smaller. Cryoslash presented a unique C–H in plane structure from nanocellulose, related to a decrease in average size of fibrils, while crystallinity and thermal properties of nanocellulose remained stable at 60 steps, but mechanical properties increased until 120 steps along with the transmittance values related to the energy consumption curve.
{"title":"Cryoslash as an effective pre-treatment to obtain nanofibrillated cellulose using ultra-fine friction grinder with kraft pulp","authors":"G. G. de Lima, B. Aggio, M. Matos, T. A. M. D. de Lima, B. Pereira, A. C. Pedro, W. L. Magalhães","doi":"10.1515/npprj-2022-0091","DOIUrl":"https://doi.org/10.1515/npprj-2022-0091","url":null,"abstract":"Abstract Approaches to obtain nanocellulose have been extensively suggested, and among the most competitive methodologies includes mechanical defibrillation, which results in a nanocellulose gel suspension that can be used in a variety of applications. However, standard procedures results in inhomogeneous fibre sizes due to its physical approach. Pre-treatments have been suggested, such as enzymes, but their cost is a disadvantage. In this work, we suggest the use of cryoslash for bleach kraft pulp using a simple methodology of embedding the dry kraft pulp in distilled water following by freezing at −80 °C, which was slashed using a common blender and submitted to an ultra-fine friction grinder. Samples were studied at various grinding steps 5, 15, 30, 60 and 120. Overall, the energy difference required to defibrillate with cryoslash was ∼3.26 kWh/kg at 30 steps and ∼6 at 120 steps, which was similar to enzymatic pre-treatment with nanofibrils significantly smaller. Cryoslash presented a unique C–H in plane structure from nanocellulose, related to a decrease in average size of fibrils, while crystallinity and thermal properties of nanocellulose remained stable at 60 steps, but mechanical properties increased until 120 steps along with the transmittance values related to the energy consumption curve.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"333 - 341"},"PeriodicalIF":1.2,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48829010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tatiana Aurora Condezo Castro, M. Cardoso, Ana Augusta Passos Rezende, Angélica de Cássia Oliveira Carneiro, Larissa Quartaroli, Cláudio Mudadu Silva
Abstract The uses of kraft lignin (KL), obtained from the black liquor (BL) in the pulping process, allow the production of activated carbon (AC), a product with high added value in the pulp mill. The AC can be used in three different sectors in a cellulose pulp mill: sectorial treatment of the cellulosic pulp bleaching filtrates; wastewater treatment; and in the treatment of water received by the mill. Thus, this article considers the steps in the production of AC, their types, and the advantages and challenges of its use in the kraft cellulose pulp mill as well as in other industries.
{"title":"Possible alternatives for using kraft lignin as activated carbon in pulp mills – a review","authors":"Tatiana Aurora Condezo Castro, M. Cardoso, Ana Augusta Passos Rezende, Angélica de Cássia Oliveira Carneiro, Larissa Quartaroli, Cláudio Mudadu Silva","doi":"10.1515/npprj-2022-0099","DOIUrl":"https://doi.org/10.1515/npprj-2022-0099","url":null,"abstract":"Abstract The uses of kraft lignin (KL), obtained from the black liquor (BL) in the pulping process, allow the production of activated carbon (AC), a product with high added value in the pulp mill. The AC can be used in three different sectors in a cellulose pulp mill: sectorial treatment of the cellulosic pulp bleaching filtrates; wastewater treatment; and in the treatment of water received by the mill. Thus, this article considers the steps in the production of AC, their types, and the advantages and challenges of its use in the kraft cellulose pulp mill as well as in other industries.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"209 - 228"},"PeriodicalIF":1.2,"publicationDate":"2023-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43621919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lorran de Sousa Arantes, Adriano Reis Prazeres Mascarenhas, M. V. Scatolino, Gustavo Henrique Denzin Tonoli, L. Mendes, Ianca Oliveira Borges, J. B. Guimarães Júnior
Abstract In this study, the effect of different concentrations of calcium hydroxide (Ca(OH)2) was evaluated as a pre-treatment for accelerated carbonation and its influence on the fibrillation of cellulosic pulps to obtain nanofibrils, and its application as a coating agent for papers. Eucalyptus (EUC) and Pine (PIN) unbleached cellulosic fibers were submitted to pre-treatment with Ca(OH)2 at concentrations of 5 and 10% and subjected to accelerated carbonation, being subsequently mechanically fibrillated to produce cellulose nanofibrils (CNF). Pretreatment with calcium hydroxide followed by accelerated carbonation provided a 35% reduction in energy consumption. Cellulosic pulps EUC and PIN pretreated with calcium hydroxide showed higher fibrillation efficiency. There was a reduction in the cobb test values for papers coated with CNF in PIN. The WVP was lower for papers coated with CNF of EUC and control PIN. The CNF coating of EUC and PIN provided an oil barrier for the kit 11 solution. The CNF coating improved the dispersion of PVA and PVOH. The papers coated in this work have the potential to be used as packaging for fatty and oily foods or as a spreading agent for other industrial coatings.
{"title":"Pre-treatment with calcium hydroxide and accelerated carbonation for cellulosic pulp fibrillation","authors":"Lorran de Sousa Arantes, Adriano Reis Prazeres Mascarenhas, M. V. Scatolino, Gustavo Henrique Denzin Tonoli, L. Mendes, Ianca Oliveira Borges, J. B. Guimarães Júnior","doi":"10.1515/npprj-2022-0101","DOIUrl":"https://doi.org/10.1515/npprj-2022-0101","url":null,"abstract":"Abstract In this study, the effect of different concentrations of calcium hydroxide (Ca(OH)2) was evaluated as a pre-treatment for accelerated carbonation and its influence on the fibrillation of cellulosic pulps to obtain nanofibrils, and its application as a coating agent for papers. Eucalyptus (EUC) and Pine (PIN) unbleached cellulosic fibers were submitted to pre-treatment with Ca(OH)2 at concentrations of 5 and 10% and subjected to accelerated carbonation, being subsequently mechanically fibrillated to produce cellulose nanofibrils (CNF). Pretreatment with calcium hydroxide followed by accelerated carbonation provided a 35% reduction in energy consumption. Cellulosic pulps EUC and PIN pretreated with calcium hydroxide showed higher fibrillation efficiency. There was a reduction in the cobb test values for papers coated with CNF in PIN. The WVP was lower for papers coated with CNF of EUC and control PIN. The CNF coating of EUC and PIN provided an oil barrier for the kit 11 solution. The CNF coating improved the dispersion of PVA and PVOH. The papers coated in this work have the potential to be used as packaging for fatty and oily foods or as a spreading agent for other industrial coatings.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"343 - 358"},"PeriodicalIF":1.2,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42857213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Mirzaei, Arthur P. Thompson Johnson, J. Panek, George Mwangi
Abstract For coated paperboard with large deformations, there is limited knowledge on the mechanisms that lead to coating damage and on the key properties that affect damage. Large deformations produce complex non-linear mechanical responses which often result in significant internal damage. The objective of this work was to establish methods to directly measure local deformation at a fold using a stereo digital image correlation (DIC) technique and a folding device designed in-house. This allowed monitoring of deformation from both cross-section and surface views, from which curvature and strain could be analyzed. This approach allowed observation and quantification of the initiation and propagation of damage. Testing showed that elastic estimation of deformation is valid only at very small curvatures but is still qualitatively useful. It was found that CD fold line shows a lower strain than MD fold line at a given curvature, but it ultimately reaches a higher level of surface strain. Additionally, localized maximum surface strain was shown to correlate better with surface damage at fold than the average surface strain. Furthermore, the introduced discontinuity index can provide a useful tool to compare surface damage at fold even for paperboard samples with different thicknesses.
{"title":"Assessment of paperboard large deformation at fold using digital image correlation technique","authors":"B. Mirzaei, Arthur P. Thompson Johnson, J. Panek, George Mwangi","doi":"10.1515/npprj-2022-0088","DOIUrl":"https://doi.org/10.1515/npprj-2022-0088","url":null,"abstract":"Abstract For coated paperboard with large deformations, there is limited knowledge on the mechanisms that lead to coating damage and on the key properties that affect damage. Large deformations produce complex non-linear mechanical responses which often result in significant internal damage. The objective of this work was to establish methods to directly measure local deformation at a fold using a stereo digital image correlation (DIC) technique and a folding device designed in-house. This allowed monitoring of deformation from both cross-section and surface views, from which curvature and strain could be analyzed. This approach allowed observation and quantification of the initiation and propagation of damage. Testing showed that elastic estimation of deformation is valid only at very small curvatures but is still qualitatively useful. It was found that CD fold line shows a lower strain than MD fold line at a given curvature, but it ultimately reaches a higher level of surface strain. Additionally, localized maximum surface strain was shown to correlate better with surface damage at fold than the average surface strain. Furthermore, the introduced discontinuity index can provide a useful tool to compare surface damage at fold even for paperboard samples with different thicknesses.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"261 - 269"},"PeriodicalIF":1.2,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48655214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Allan de Amorim dos Santos, Lays Camila Matos, M. Mendonça, M. Muguet, Andrea Ponzecchi, A. Sanadi, G. Tonoli
Abstract In this work, we aimed to analyze suspensions of cationic starch by adding 5 wt%, 7 wt%, and 10 wt% of bentonite as a bilayer coating on kraftliner paper (85 g/m2). The controls were doubly-wet-and-dry and uncoated kraftliner paper. In a coating machine, the formulations were applied until reaching a grammage of 15 g/m2 and then dried at 103 ± 2 °C. The test was carried out about pH, solids content, and viscosity of the suspensions. The physical characteristics of the coated papers were evaluated, as well as their ability to block water, water vapor, and oil/grease. We also analyzed with scanning electron microscopy, Raman spectroscopy, and Fourier transform infrared spectroscopy. The packaging, having a water contact angle of up to 78° and 189 g/m² for Cobb, showed a low resistance to water, which is further responsible for decreased mechanical resistance. Nevertheless, the coating did not change the permeability to water vapor, however, bentonite promoted a decrease in wettability and Cobb value of the paper. The addition of 7 wt% bentonite to the cationic starch matrix promoted high oil resistance with 12 for kit-oil, while 10 wt% bentonite promoted greater pencil hardness, with a value of 8H. Bentonite strength and cationic starch showed good interaction, increasing oil resistance.
{"title":"Addition of bentonite to cationic starch matrix for coating on kraftliner paper to improve grease resistance","authors":"Allan de Amorim dos Santos, Lays Camila Matos, M. Mendonça, M. Muguet, Andrea Ponzecchi, A. Sanadi, G. Tonoli","doi":"10.1515/npprj-2022-0104","DOIUrl":"https://doi.org/10.1515/npprj-2022-0104","url":null,"abstract":"Abstract In this work, we aimed to analyze suspensions of cationic starch by adding 5 wt%, 7 wt%, and 10 wt% of bentonite as a bilayer coating on kraftliner paper (85 g/m2). The controls were doubly-wet-and-dry and uncoated kraftliner paper. In a coating machine, the formulations were applied until reaching a grammage of 15 g/m2 and then dried at 103 ± 2 °C. The test was carried out about pH, solids content, and viscosity of the suspensions. The physical characteristics of the coated papers were evaluated, as well as their ability to block water, water vapor, and oil/grease. We also analyzed with scanning electron microscopy, Raman spectroscopy, and Fourier transform infrared spectroscopy. The packaging, having a water contact angle of up to 78° and 189 g/m² for Cobb, showed a low resistance to water, which is further responsible for decreased mechanical resistance. Nevertheless, the coating did not change the permeability to water vapor, however, bentonite promoted a decrease in wettability and Cobb value of the paper. The addition of 7 wt% bentonite to the cationic starch matrix promoted high oil resistance with 12 for kit-oil, while 10 wt% bentonite promoted greater pencil hardness, with a value of 8H. Bentonite strength and cationic starch showed good interaction, increasing oil resistance.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"285 - 300"},"PeriodicalIF":1.2,"publicationDate":"2023-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43588476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This study developed an efficient and green method for isolating and purifying lignin from black liquor (BL) using deep eutectic solvents (DESs). After the short and mild process (700 W microwave-assisted, 100 °C, DES: BL 1:5 (v: v), 30 min) using optimized DES (lactic acid (LA): choline chloride (ChCl) 10:1, molar ratio), the yield and purity of lignin obtained from 100 mL BL was 1.58 g and 88.12%, respectively, which was more efficient than the results of 1.18 g and 78.54% of the conventional process. Furthermore, more than 95% of initial results were obtained after three cycles. The composition and structure of DESs and conventionally purified lignin were slightly different. The solvent costs for both processes were also evaluated, showing that the DES process has great potential to replace traditional bulky and environmentally unfriendly procedures for lignin isolation and purification and to help develop new strategies for the potential added value of lignin.
{"title":"Efficient and eco-friendly isolation and purification of lignin from black liquor with choline chloride-based deep eutectic solvents","authors":"Zhuang Liu, Yi Hou, Chao Liu, Song-Qing Hu","doi":"10.1515/npprj-2022-0093","DOIUrl":"https://doi.org/10.1515/npprj-2022-0093","url":null,"abstract":"Abstract This study developed an efficient and green method for isolating and purifying lignin from black liquor (BL) using deep eutectic solvents (DESs). After the short and mild process (700 W microwave-assisted, 100 °C, DES: BL 1:5 (v: v), 30 min) using optimized DES (lactic acid (LA): choline chloride (ChCl) 10:1, molar ratio), the yield and purity of lignin obtained from 100 mL BL was 1.58 g and 88.12%, respectively, which was more efficient than the results of 1.18 g and 78.54% of the conventional process. Furthermore, more than 95% of initial results were obtained after three cycles. The composition and structure of DESs and conventionally purified lignin were slightly different. The solvent costs for both processes were also evaluated, showing that the DES process has great potential to replace traditional bulky and environmentally unfriendly procedures for lignin isolation and purification and to help develop new strategies for the potential added value of lignin.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"367 - 380"},"PeriodicalIF":1.2,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44037465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lihong Zhao, Xun Ke, Zhiwei Wang, Min Wu, Junrong Li, L. Qian, Junli Ren
Abstract In order to solve the conflict between precipitated calcium carbonate (PCC) filling and alkyl ketene dimer (AKD) sizing for paper, this study explored two new flocculation methods: AKD and PCC were flocculated separately in the process ((A)(P)F), while the two pre-flocs from AKD and PCC were blended in the process ((AP)F). The result showed that increasing the dosage of the flocculant cationic starch (CS) resulted in a significant growth in the median size of PCC flocs and reduction in the specific surface area, turbidity, the negative charge of Zeta potential, as well as the adsorption capacity of PCC to AKD. Consequently the sizing degree and filler retention rate of the handsheets rose markedly. With 125 mg g−1 of CS, compared with the conventional process, the filler retention rate for (A)(P)F grew up to 86.16%; the Cobb60 values for both (AP)F and (A)(P)F declined, and the contact angle (CA) increased to 120.65° and 127.65° respectively. At the same time, the filler bondability factor (FBF) were increased due to the intensified bonding force between fibers, and resultantly the comparable mechanical properties of papersheets with a high level of filler retention was obtained from (AP)F and (A)(P)F flocculation processes.
{"title":"Flocculation of alkyl ketene dimer and calcium carbonate on paper sizing and filling performance","authors":"Lihong Zhao, Xun Ke, Zhiwei Wang, Min Wu, Junrong Li, L. Qian, Junli Ren","doi":"10.1515/npprj-2022-0079","DOIUrl":"https://doi.org/10.1515/npprj-2022-0079","url":null,"abstract":"Abstract In order to solve the conflict between precipitated calcium carbonate (PCC) filling and alkyl ketene dimer (AKD) sizing for paper, this study explored two new flocculation methods: AKD and PCC were flocculated separately in the process ((A)(P)F), while the two pre-flocs from AKD and PCC were blended in the process ((AP)F). The result showed that increasing the dosage of the flocculant cationic starch (CS) resulted in a significant growth in the median size of PCC flocs and reduction in the specific surface area, turbidity, the negative charge of Zeta potential, as well as the adsorption capacity of PCC to AKD. Consequently the sizing degree and filler retention rate of the handsheets rose markedly. With 125 mg g−1 of CS, compared with the conventional process, the filler retention rate for (A)(P)F grew up to 86.16%; the Cobb60 values for both (AP)F and (A)(P)F declined, and the contact angle (CA) increased to 120.65° and 127.65° respectively. At the same time, the filler bondability factor (FBF) were increased due to the intensified bonding force between fibers, and resultantly the comparable mechanical properties of papersheets with a high level of filler retention was obtained from (AP)F and (A)(P)F flocculation processes.","PeriodicalId":19315,"journal":{"name":"Nordic Pulp & Paper Research Journal","volume":"38 1","pages":"381 - 387"},"PeriodicalIF":1.2,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41854803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}