scholarly journals Influence of lignin content in cellulose pulp on paper durability

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Edyta Małachowska ◽  
Marcin Dubowik ◽  
Piotr Boruszewski ◽  
Joanna Łojewska ◽  
Piotr Przybysz
Keyword(s):  
Lignin Content ◽  
Mechanical Tests ◽  
Accelerated Ageing ◽  
Common Belief ◽  
Oxidation Reactions ◽  
Cellulose Pulp ◽  
Aluminium Sulfate ◽  
Vis Spectroscopy ◽  
Ageing Rate ◽  
Hydrolysis Of

AbstractPaper degradation on a macroscopic scale is characterised primarily by yellowing, an increase in brittleness, and other destructive changes caused by the hydrolysis of glycoside bonds and oxidation reactions. Until now, lignin has been believed to cause these changes. However, contemporary analysis has not confirmed this assumption and has attributed low paper resistance to ageing with acidification owing to the production in acid environments that involve aluminium sulfate. In view of the common belief this manuscript presents studies on the accelerated ageing of papers with different lignin contents that are produced in neutral environments. To achieve the objective, artificially aged papers under conditions of increased humidity and temperature were investigated using chromatographic (SEC) and spectroscopic (FTIR and UV–Vis spectroscopy) techniques. Mechanical tests were used to determine the decrease in tensile properties of the samples. We observed no effects of the lignin content on the ageing rate of paper produced at neutral pH. This work also reveals the extent to which spectroscopic methods are useful for studying the papers containing lignin.

scholarly journals Process Development for Flexible Films of Industrial Cellulose Pulp Using Superbase Ionic Liquids

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1767
Author(s):  
Diana C. M. Ribeiro ◽  
Rafael C. Rebelo ◽  
Francesco De Bon ◽  
Jorge F. J. Coelho ◽  
Arménio C. Serra
Keyword(s):  
Ionic Liquids ◽  
Process Development ◽  
Mechanical Tests ◽  
Proton Nuclear Magnetic Resonance ◽  
Daily Routine ◽  
Scanning Calorimetry ◽  
Transparent Films ◽  
Cellulose Pulp ◽  
Flexible Films ◽  
Vis Spectroscopy

Due to environmental concerns, more attention has been given to the development of bio-based materials for substitution of fossil-based ones. Moreover, paper use is essential in daily routine and several applications of industrial pulp can be developed. In this study, transparent films were produced by industrial cellulose pulp solubilization in tetramethylguanidine based ionic liquids followed by its regeneration. Films were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV/Vis spectroscopy, proton nuclear magnetic resonance (1H-NMR), dynamic scanning calorimetry (DSC), thermal analysis (TG), and X-ray diffraction (XRD). Mechanical tests showed that films have a good elongation property, up to 50%, depending on ionic liquid incorporation. The influence of the conjugated acid and dissolution temperature on mechanical properties were evaluated. These results revealed the potential of this methodology for the preparation of new biobased films.

scholarly journals Helmet Phthalocyaninato Iron Complex as a Primary Drier for Alkyd Paints

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1220
Author(s):  
Jan Honzíček ◽  
Eliška Matušková ◽  
Štěpán Voneš ◽  
Jaromír Vinklárek
Keyword(s):  
Catalytic Performance ◽  
Mechanical Tests ◽  
Iron Complex ◽  
Kinetic Measurements ◽  
Time Resolved ◽  
Strong Activity ◽  
Vis Spectroscopy ◽  
Order Of Magnitude ◽  
Transparent Coatings ◽  
Time Resolved Infrared Spectroscopy

This study describes the catalytic performance of an iron(III) complex bearing a phthalocyaninato-like ligand in two solvent-borne and two high-solid alkyd binders. Standardized mechanical tests revealed strong activity, which appeared in particular cases at concentrations about one order of magnitude lower than in the case of cobalt(II) 2-ethylhexanoate, widespread used in paint-producing industry. The effect of the iron(III) compound on autoxidation process, responsible for alkyd curing, was quantified by kinetic measurements by time-resolved infrared spectroscopy and compared with several primary driers. Effect of the drier concentration on coloration of transparent coatings was determined by UV–Vis spectroscopy.

Preparation of Highly Conductive Polyaniline in Carbamide Aqueous Solution Using SnCl4 as Initiator

2012 ◽  
Vol 476-478 ◽  
pp. 2205-2208 ◽  
Author(s):  
Guan Nan Lin ◽  
Qun Yu ◽  
Wei Wang ◽  
Gui Bao Wang
Keyword(s):  
Aqueous Solution ◽  
Ammonium Persulfate ◽  
Conductivity Measurements ◽  
X Ray ◽  
New Class ◽  
Vis Spectroscopy ◽  
Polymerization System ◽  
Novel Method ◽  
Conductive Polyaniline ◽  
Hydrolysis Of

In this paper, we demonstrated a novel method for the preparation of highly conductive polyaniline (PANI) compounded with Sn(OH)4. We obtained the PANI directly in the oxidation polymerization system via simultaneous reaction of aniline (using ammonium persulfate, APS as oxidant) and SnCl4 in carbamide aqueous solution. The resulting PANI was compounded with Sn(OH)4 had been characterized by FTIR, UV-Vis spectroscopy, X-ray diffractometry, thermal analysis, scanning electron microscope and conductivity measurements, and the results showed that PANI was in well doped state due to the hydrolysis of APS and the complex between PANI and Sn(OH)4. We are sure this alkali-guided polymerization to obtain conductive PANI will lead to the preparation of a new class of PANI composites.

scholarly journals Preparation and Characterization of New Environmentally Friendly Starch-Cellulose Materials Modified with Casein or Gelatin for Agricultural Applications

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1684 ◽  
Author(s):  
Mirosława Prochoń ◽  
Anna Marzec ◽  
Bolesław Szadkowski
Keyword(s):  
Chemical Properties ◽  
Mechanical Tests ◽  
Infrared Analysis ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Cellulose Composites ◽  
Vis Spectroscopy ◽  
Agricultural Applications ◽  
Starch Films ◽  
Cellulose Fabrics

The purpose of this work was to prepare new biodegradable starch-cellulose composites, with starch, using casein and gelatin as natural nutrients. The physico-chemical properties of the starch films and cellulose fabrics with starch coatings were studied by Fourier transformation infrared analysis, laser confocal scanning microscopy (LCSM), scanning electron microscopy (SEM), UV-Vis spectroscopy, swelling tests, mechanical tests, thermal analysis thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The susceptibility of the starch films to biodegradation was investigated, together with their resistance to thermo-oxidative aging. As a result of the formation of the starch films, both the casein and gelatin macromolecules were able to interact directly with the starch matrix and the fractions of unbranched amylose and branched amylopectin it contained. This interaction was visible as changes in the absorption bands of the polar groups, as revealed by infrared analysis. Spectral analysis of the cellulose fabrics coated with starch films suggests that hydrogen bridges formed between the micelles of long cellulose filaments and the micro and macro-fibers of the starch pectins. An applicative test revealed that when used as a covering for bean cultivation the cellulose-starch composites act as a fertilizing component, contributing to significantly improved growth of Phaseolus vulgaris in comparison to the use of unmodified cellulose.

scholarly journals Copper Complexes of Benzoylacetone Bis-Thiosemicarbazones: Metal and Ligand Based Redox Reactivity

2021 ◽  
Vol 74 (1) ◽  
pp. 34 ◽  
Author(s):  
Jessica K. Bilyj ◽  
Jeffrey R. Harmer ◽  
Paul V. Bernhardt
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Cyclic Voltammetry ◽  
Copper Complexes ◽  
Atmospheric Oxygen ◽  
The Other ◽  
Oxidation Reactions ◽  
Paramagnetic Resonance ◽  
Time Resolved ◽  
Vis Spectroscopy ◽  
Electron Paramagnetic

Bis-thiosemicarbazones derived from the β-diketone benzoylacetone (H3banR, R=Me, Et, Ph) are potentially tetradentate N2S2 ligands whose coordination chemistry with copper is reported. In the absence of oxygen and in the presence of base they form anionic CuII complexes of the fully deprotonated ligands [CuII(banR)]–. Upon exposure to atmospheric oxygen they undergo a complex series of reactions leading to two types of products; one a ligand oxidised ketone complex [CuII(banRO)] and the other an unprecedented dimeric di-CuIII complex [(CuIII(banR))2] depending on the R substituent. Time-resolved UV-vis spectroscopy, cyclic voltammetry, spectroelectrochemistry, and electron paramagnetic resonance (EPR) spectroscopy have been used to identify intermediates on the way to stable products formed under both anaerobic and aerobic conditions. It is found that both ligand-centred and Cu-centred oxidation reactions are occurring in parallel leading to this unusually complicated mixture of products.

Assessment of electrochemical and chemical coagulation as post-treatment for the effluents of a UASB reactor treating cellulose pulp mill wastewater

2005 ◽  
Vol 52 (1-2) ◽  
pp. 183-188 ◽  
Author(s):  
A.P. Buzzini ◽  
A.J. Motheo ◽  
E.C. Pires
Keyword(s):  
Kraft Pulp ◽  
Pulp Mill ◽  
Post Treatment ◽  
Color Removal ◽  
Uasb Reactor ◽  
Cellulose Pulp ◽  
Aluminium Sulfate ◽  
Treatment Processes ◽  
Simulated Wastewater ◽  
Electrolytic Treatment

This paper presents results from exploratory experiments to test the technical feasibility of electrolytic treatment and coagulation followed by flocculation and sedimentation as post-treatment for the effluent of an UASB reactor treating simulated wastewater from an unbleached Kraft pulp mill. The electrolytic treatment provided up to 67% removal of the remaining COD and 98% of color removal. To achieve these efficiencies the energy consumption ranged from 14 Wh.l−1 to 20 Wh.l−1. The coagulation-flocculation treatment followed by settling required 350–400 mg.l−1 of aluminium sulfate. The addition of a high molecular weight cationic polymer enhanced both COD and color removal. Both post-treatment processes are technically feasible.

scholarly journals Photocatalytic Abatement of Volatile Organic Compounds by TiO2 Nanoparticles Doped with Either Phosphorous or Zirconium

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2121 ◽  
Author(s):  
Melodj Dosa ◽  
Marco Piumetti ◽  
Samir Bensaid ◽  
Tahrizi Andana ◽  
Camilla Galletti ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Direct Synthesis ◽  
Ethylene Oxidation ◽  
Oxidation Reactions ◽  
X Ray ◽  
Binary Oxides ◽  
Ethylene Conversion ◽  
Vis Spectroscopy ◽  
Volatile Organic ◽  
Propylene Conversion

The aim of this work is to study the activity of novel TiO2-based photocatalysts doped with either phosphorus or zirconium under a UV-Vis source. A set of mesoporous catalysts was prepared by the direct synthesis: TiO2_A and TiO2_B (titanium oxide synthesized by two different procedures), P-TiO2 and Zr-TiO2 (binary oxides with either nonmetal or metal into the TiO2 framework). Complementary characterizations (N2 physisorption at 77 K, X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) analysis, X-ray Photoelectron Spectroscopy (XPS), and (DR)UV-Vis spectroscopy) were used to investigate the physicochemical properties of the prepared catalysts. Then, the photocatalysts were tested for the oxidation of propylene and ethylene under UV-Vis light. As a result, the most promising catalyst for both the propylene and ethylene oxidation reactions was the P-TiO2 (propylene conversion = 27.8% and ethylene conversion = 13%, TOS = 3 h), thus confirming the beneficial effect of P-doping into the TiO2 framework on the photocatalytic activity.

scholarly journals Hazardous Waste Management of Buffing Dust Collagen

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1498
Author(s):  
Miroslawa Prochon ◽  
Anna Marzec ◽  
Oleksandra Dzeikala
Keyword(s):  
Hazardous Waste ◽  
Waste Product ◽  
Mechanical Tests ◽  
Styrene Butadiene Rubber ◽  
Infrared Analysis ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Vis Spectroscopy ◽  
The Individual

Buffing Dust Collagen (BDC) is a hazardous waste product of chromium tanning bovine hides. The aim of this study was to investigate whether BDC has the desirable properties required of modern fillers. The microstructural properties of BDC were characterized by elemental analysis (N, Cr2O3) of dry residue and scanning electron microscopy (SEM). The BDC was applied (5 to 30 parts by weight) to styrene butadiene rubber (SBR), obtaining SBR-BDC composites. The physicochemical properties of the SBR-BDC composites were examined by Fourier transform infrared analysis, SEM, UV–Vis spectroscopy, swelling tests, mechanical tests, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The biodegradability of the SBR-BDC composites and their thermo-oxidative aging were also investigated. The filler contributed to increase the cross-link density in the elastomer structure, as evidenced by enhanced mechanical strength. The introduction of a filler into the elastomer structure resulted in an increase in the efficiency of polymer bonding, which was manifested by more favorable rheological and mechanical parameters. It also influenced the formation of stable interfacial bonds between the individual components in the polymer matrix, which in turn reduced the release of compact chromium in the BDC filler. This was shown by the absorption bands for polar groups in the infrared analysis and by imaging of the vulcanization process.

scholarly journals Reduction of surface area of lignin improves enzymatic hydrolysis of cellulose from hydrothermally pretreated wheat straw

RSC Advances ◽  
2014 ◽  
Vol 4 (69) ◽  
pp. 36591-36596 ◽  
Author(s):  
M. H. Sipponen ◽  
V. Pihlajaniemi ◽  
O. Pastinen ◽  
S. Laakso
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Surface Area ◽  
Lignin Content ◽  
Cellulose Conversion ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Hydrolysis Of Cellulose ◽  
Pretreated Wheat Straw ◽  
Hydrolysis Of

24 h enzymatic hydrolysis (15 FPU g−1) of solid residues from wheat straw autohydrolysis. Cellulose conversion as a function of lignin content (left) or lignin surface area (right) in solid residues.

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