Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Committees
Collections
Journal articles
Magazine articles
Editorial: TAPPI Journal welcomes four new editorial board members, TAPPI Journal October 2024
ABSTRACT: TAPPI is pleased to welcome four new members to the TAPPI Journal editorial board: Dr. Biljana Bujanovic, Dr. Ewellyn Capanema, Dr. Diego Gomez-Maldonado, and Dr. Joice Kaschuk. We are extremely pleased that they are sharing their expertise with the industry through TAPPI Journal, and you can read about their backgrounds below.
Journal articles
Magazine articles
In-situ green synthesis and adsorption on methylene blue of copper-based metal organic framework/cellulose/chitosan (CCTSA/HKUST-1) composite aerogel, TAPPI Journal October 2024
ABSTRACT: In order to explore the application of metal-organic frameworks (MOFs) in environmental and water treatment fields, a new composite aerogel of HKUST-1/cellulose/chitosan (CCTSA/HKUST-1) with better hydrostability was synthesized by an in-situ synthesis method combining covalent cross-linking and solvothermal methods as an efficient adsorbent for methylene blue (MB). The composite aerogel (CCTSA) obtained by covalent cross-linking of cellulose (CE) and chitosan (CTS) exhibited excellent stability under strong acid and solvent-thermal conditions. With the increase of CTS content, it was beneficial to the in-situ synthesis of HKUST-1, as well as to increase the mass loading rate of HKUST-1 to 37.06%, while the Brunauer-Emmett-Teller (BET) specific surface area of CCTSA/HKUST-1 composite aerogel reached 945.123 m2·g-1, which was much higher than that of the CCTSA composite aerogel (14.489 m2·g-1). The CCTSA/ HKUST-1 composite aerogel exhibited excellent adsorption capacity (537.6 mg·g-1) on MB solution, and cyclic adsorption could be achieved. This study proposes a concept of valorization of alkaline peroxide mechanical pulping (APMP) waste liquor to hemicellulose-based hydrogel. This hemicellulose-based hydrogel exhibits a sensitive temperature/pH dual response. Hemicellulose-based hydrogels swell or shrink through the change of hydrogen bond/electrostatic repulsion/charge screening. They also show good water absorption and water retention properties.
Journal articles
Magazine articles
Biofuels in lime kilns • Operating experience in the Nordic pulp and paper industry, TAPPI Journal October 2024
ABSTRACT: The lime reburning process is a central part of the chemical pulp mill. It is energy intensive and consumes large amounts of fossil fuel, globally consuming about 50 terawatt-hours (TWh) of fuel per year. Conversion to operation with biofuel is interesting, both to reduce carbon dioxide emissions and to reduce costs. Researchers interviewed managers in mills that use solid, liquid, or gasified biofuels to replace fuel oil or natural gas in their lime kilns, and they conducted surveys related to fuel consumption and operations and maintenance. In Sweden and Finland, there were ten mills in 2020 using biomass powder or gasified biomass as the primary fuel, and two more installations were under construction. There were also nine installations in operation or under construction outside the Nordic countries. Fourteen mills in Sweden and two mills in Finland used tall oil pitch as the main fuel. Fuel consumption in Swedish lime kilns was 3.8 TWh in 2020, and 90% of this energy was supplied with biofuels. Of about 4.2 TWh used in Finnish lime kilns, approximately 45% was supplied with biofuels. Developments in the design of the fuel supply system include belt dryers being used in all new installations and mass flow metered dosing systems being used in most new pulverized fuel installations. Bark gasifiers have increased considerably in size. Lignin powder firing has been established as a proven option. A solution for many Swedish and Finnish mills is the use of tall oil pitch as a replacement for fuel oil.
Journal articles
Magazine articles
Model development for real oxygen delignification processes, TAPPI Journal October 2024
ABSTRACT: Previous extensive work has been done on modeling the oxygen delignification process, based on how the basic parameters, i.e., temperature, kappa number, concentration of alkali, and concentration of oxygen, affect the delignification rate. However, these models are not used extensively to evaluate the performance of real processes, primarily because they have not been able to properly consider all the essential issues affecting delignification in practice. Such issues include the mass transfer and consumption of oxygen, which defines the concentration of dissolved oxygen in the process, and the effect of that concentration on the delignification rate. In this paper, a new way to model the oxygen delignification process is used in which these parameters, among other smaller matters, are taken into account. The basic model and its parameters were defined by the information obtained from the literature, delignification made in the laboratory tests, and mill processes and mill tests. An essential aspect of these studies was the information obtained from the oxygen concentration measured in the residual gas obtained from the top of the reactor. With the aid of this measurement, it was possible to define more accurately the consumption of oxygen and partial pressure of oxygen that define the concentration of dissolved oxygen in the reactor. Using mill experiments, a model was formed that predicts the operation of the oxygen delignification process. The model was used to show how much the process could be improved by optimizing the charge of the oxygen. The mill experiments also confirmed that mass transfer of oxygen is modeled correctly enough, except when the charge of oxygen is very low and/or the mixing is not efficient enough. In that case, there is variation in the concentration of oxygen in the process that should be taken into account in the modeling.
Journal articles
Magazine articles
Colloid chemical aspects of paper formation in the presence of nanofibrillated cellulose and cationic starch, TAPPI Journal September 2024
ABSTRACT: A series of experimental tests were carried out to examine colloidal-scale consequences of optionally treating nanofibrillated cellulose (NFC) with cationic starches of different charge density and dosage (0.5% or 2.0% by weight), adding that material to a furnish prepared from 100% recycled copy paper, and then subjecting the mixture to very different levels of hydrodynamic shear. Tests included optical microscopy, sediment volume tests, sediment velocity tests, and “percent fines” assessment by means of a fiber quality analyzer (FQA). In addition, the zeta potential and charge demand of the studied materials were evaluated. Optical imaging revealed that cationic starch treatment of the NFC tended to agglomerate it into multiparticle clusters, which sometimes could be mostly redispersed by hydrodynamic shear. Subsequent addition of the starch-treated NFC to the default furnish resulted in much of the colloidal material becoming attached to fibers. Subsequent shearing of the mixtures was at least partly effective in separating the clusters of NFC from the fiber surface, resulting in essentially a two-component mixture. Multiparticle NFC clusters coexisted with the fiber suspension, sometimes attached and sometimes not, depending on the details of treatments. Sediment volume tests showed that systems containing cationic starch-treated NFC tended to have a higher density after settling in comparison to untreated NFC; these findings are consistent with the cationic starch acting as a stabilizer on the solid surfaces, allowing them to slide past each other during the settling process. Application of intense hydrodynamic shear tended to result in denser sediment. Results of tests with the sediment velocity messurement and the FQA percent fines assessment did not correlate well with changes in test conditions considered in this study.
Journal articles
Magazine articles
Editorial: Transform presentations to TAPPI Journal research papers by following basic steps, TAPPI Journal August 2024
ABSTRACT: Very often, important research findings are communicated in presentation form at industry conferences like those TAPPI holds. While this is a great way to highlight your work, it has some limitations when compared to a peer-reviewed TAPPI Journal paper. Presentations are limited to a specific event, while publishing papers in a peer-reviewed journal means that your work becomes part of scientific literature that is available to a broader audience. Also, a research paper allows for a more detailed explanation of the methods, data, and conclusions than the time-constrained format of a presentation.
Journal articles
Magazine articles
Convolutional neural networks enhance pyrolysis gas chromatography mass spectrometry identification of coated papers, TAPPI Journal August 2024
ABSTRACT: In the evolving paper industry, accurate identification of coated paper components is essential for sustainability and recycling efforts. This study employed pyrolysis-gas chromatography mass spectrometry (Py-GCMS) to examine six types of coated paper. A key finding was the minimal interference of the paper substrate with the pyrolysis products of the coatings, ensuring reliable analysis. A one-dimensional convolutional neural network (1D-CNN) was employed to process the extracted ion chromatograms directly, simplifying the workflow and achieving a predictive accuracy of 95.2% in identifying different coating compositions. Additionally, the study high-lighted the importance of selecting an optimal pyrolysis temperature for effective feature extraction in machine learning models. Specific markers for coated papers, including polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polybutylene succinate (PBS), polylactic acid (PLA), and waterborne polyacrylates (WP), were identified. This research demonstrates a novel approach to coated paper identification by combining Py-GCMS with machine learning, offering a foundation for further studies in product quality and environmental impact.
Journal articles
Magazine articles
Production and characterization of furanic bio-oil from Kawayan kiling (Bambusa vulgaris Schrad ex. Wendl) using molten citric acid in an open system, TAPPI Journal August 2024
ABSTRACT: The burning of fossil fuels poses many threats to the environment. These predicaments have led to a continuous search for alternative sources and production of energy, and biomass is considered the most abundant renewable energy source. In this study, the potential to produce furanic bio-oil from the cellulose of Bambusa vulgaris was explored. The proximate chemical analysis of bamboo was determined using TAPPI Standards. Cellulose was isolated through dewaxing, delignification, and alkaline treatments. The furanic bio-oil was produced by mixing cellulose and citric acid in a solvent-free environment. The effects of the digestion time (120 min, 180 min, and 240 min) on the yield and characteristics were determined. The chemical compositions were determined using Fourier transform infrared (FTIR) spectroscopy and gas chromatography-mass spectrometry (GCMS). B. vulgaris has the following chemical composition: alpha-cellulose (57.42 ± 0.40), holocellulose (78.84 ± 0.52), lig-nin (28.85 ± 0.17), hot water extractives (3.99 ± 0.08), organic extractives (0.77 ± 0.04), ash (4.67 ± 0.02), and moisture (12.98 ± 0.22). The bio-oil yield was affected by the digestion time. The highest yield was obtained at 180 min, followed by 120 min, and 240 min with 88.59%, 59.28%, and 49.96%, respectively. The peaks in the FTIR spectra corresponded to the compounds determined by the GCMS analysis. The dominant chemicals were furans (29.19%), ketones (26.31%), and carboxylic acids (19.26%). The bio-oil obtained at 180-min digestion time has the following properties: sulfur content (0.032 wt%), kinematic viscosity (1.03 mm2/s), specific gravity (0.925), copper corrosion test (No. 1a), pH (2.753), and water content (not detected). Overall, the obtained values from the properties and chemical characterization can be the basis for investigating its performance for biofuel production and utilization. This study is aligned with the Bamboo Industry’s Strategic Science and Technology Plan for the Philippines to develop other value-added products from bamboo and to achieve Sustainable Development Goal 7 (SDG 7) as determined by the United Nations.
Journal articles
Magazine articles
Sulfur makeup in an unbleached kraft pulp mill, TAPPI Journal August 2024
ABSTRACT: Sodium sesquisulfate or “sesqui” (Na3H(SO4)2) is a by-product of chlorine dioxide production at kraft pulp mills. It is typically used for sodium and sulfur makeup in the liquor loop. Mondi Hinton Inc. (MHI) in Hinton, AB, Canada, was converting from bleached to unbleached kraft pulp production and was thus losing this source of makeup. The only option that was readily available as a substitute was sodium hydrosulfide (NaHS), which was cost prohibitive. Other options such as sodium sulfate (Na2SO4), emulsified sulfur, sulfuric acid (H2SO4), and sodium bisulfite (NaHSO3) were compared. The mill concluded that pelletized sulfur plus sodium hydroxide or “caustic soda” (NaOH) was the best option. Laboratory-scale experiments showed that pelletized sulfur dissolved in white liquor (WL). A mill-scale trial revealed that pelletized sulfur added to a causticizer had no adverse impacts on the downstream pressure filters or kiln operation. The sulfur reacted to produce polysulfide upstream of the WL storage tank, giving the liquor an orange hue. This polysulfide appeared to partially degrade into thiosulfate before being fed to the digester. The heavy black liquor (HBL) sulfur:sodium (S:Na) ratio did not change significantly, even though the sulfur/soda addition location was upstream of the original one. In addition, other properties such as liquor heating value and elemental analysis did not significantly change. Due to polysulfide/thiosulfate concentration in the white liquor, it was determined that the carbon steel equipment was at risk for corrosion. During the annual turnaround that occurred eight months after the addition of sulfur was started, the wash zone of the digester showed no signs of thinning/damage. The mill has been running exclusively with pelletized sulfur for 22 months (as of August 2024), realizing significant cost savings compared to the use of NaHS or other sulfur/soda addition options.
Journal articles
Magazine articles
Editoral: Investing in the future: Writing and peer-reviewing for TAPPI Journal, TAPPI Journal July 2024
ABSTRACT: Those who actively participate in TAPPI realize how much there is to gain from the networking, educational resources, career development, and other opportunities that come with this involvement. One important opportunity is the ability to share your work and expertise with others in your field, and an excellent way to do this is by taking part in the TAPPI Journal peer-review process, either as an author or a reviewer or both.