Use of sweet sorghum bagasse (Sorghum bicolor (L.) Moench) for cellulose acetate synthesis

The objective of this work was to synthesize cellulose acetate from sorghum bagasse, a promising raw material for the production of chemical inputs, both from a photosynthetic point of view and the maturation speed compared with that of sugarcane. The bagasse was treated with hydrogen peroxide, and then cellulose was isolated using sodium chlorite, acetic acid, and sodium hydroxide. The cellulose was subjected to an acetylation reaction, from which cellulose triacetate was obtained. By means of statistical analysis, it was observed that the conditions that generated the highest solubilization of lignin (62%) and higher yield from cellulose extraction (39.5%) were 60 °C, a 6% peroxide concentration, and 4 h. Cellulose acetate was obtained with a degree of substitution of 3.66 at 25 °C and 24 h. Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry, differential thermogravimetry, and differential scanning calorimetry analyses confirmed that the obtained cellulose presented specific characteristics of this material. Also, the reaction of acetylation was confirmed through these techniques.

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The Application of Seabed Silt in the Preparation of Artificial Algal Reefs

Applied Sciences ◽

10.3390/app10207279 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7279 ◽

Cited By ~ 1

Author(s):

Zhaoyang Jiang ◽

Jiating Zhang ◽

Zhaoyi Nie ◽

Zhansheng Guo ◽

Lixin Zhu ◽

...

Keyword(s):

Biological Effects ◽

Coastal Development ◽

Raw Material ◽

Artificial Reefs ◽

Strength Development ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Environmental Disasters ◽

Compressive Strength Development ◽

Dissolve Nitrogen

Large amounts of silt have been deposited on the seabed in China’s coastal areas due to intensive coastal development and marine raft aquaculture, which are the main causes of local marine environmental disasters. In this study, seabed silt was tested as a potential raw material for artificial reefs. The silt was mixed with cement in four proportions to create concrete specimens for use in silt artificial reefs (SARs). The compressive strength development and nutrient dissolution were examined in the SAR specimens. The hydration products of the SAR paste were investigated through X-ray diffraction (XRD), scanning election microscope (SEM), and differential scanning calorimetry (DSC) techniques. The results showed that the compression strength of the SAR specimens was inversely proportional to their seabed silt content. The SAR specimens were able to continuously dissolve nitrogen-containing nutrients. The presence of Ca(OH)2, commonly found in traditional concrete, was not detected, which may help improve the seaweed adhesion and biological effects of artificial reefs. The effective utilization of seabed silt could serve to restore and improve the marine ecological environment.

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Characterization of Li2O-Al2O3-SiO2 glass-ceramics produced from a Brazilian spodumene concentrate

Cerâmica ◽

10.1590/0366-69132019653752699 ◽

2019 ◽

Vol 65 (375) ◽

pp. 366-377 ◽

Cited By ~ 2

Author(s):

L. B. Rebouças ◽

M. T. Souza ◽

F. Raupp-Pereira ◽

A. P. Novaes de Oliveira

Keyword(s):

Structural Changes ◽

Glass Ceramics ◽

Nucleating Agent ◽

Raw Material ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Heating Microscopy ◽

Shock Resistance ◽

High Thermal Shock Resistance

Abstract Glass-ceramics in the LAS (Li2O-Al2O3-SiO2) system with high thermal shock resistance were successfully obtained using Brazilian spodumene concentrate as the main raw material (80-70 wt%). Two compositions (Li2O.Al2O3.nSiO2) were produced with n= 2 and 4, near to the stoichiometric compositions of β-eucryptite and β-spodumene. The characteristic temperatures of parent glasses were determined by contact dilatometry, differential scanning calorimetry and heating microscopy. The crystallization mechanism and the effect of the nucleating agent (TiO2.2ZrO2) required to promote volume crystallization in the parent glasses were investigated. Microstructural and structural changes with temperature were also evaluated by optical microscopy and X-ray diffraction. The obtained glass-ceramics presented coefficients of thermal expansion between -0.370x10-6 and 4.501x10-6 °C-1 in the 22 to 700 °C range.

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Preparation of an Asymmetric Membrane from Sugarcane Bagasse Using DMSO as Green Solvent

Applied Sciences ◽

10.3390/app9163347 ◽

2019 ◽

Vol 9 (16) ◽

pp. 3347 ◽

Cited By ~ 3

Author(s):

Nu ◽

Hung ◽

Hoang ◽

Van der Bruggen

Keyword(s):

Cellulose Acetate ◽

Sugarcane Bagasse ◽

Raw Material ◽

Cellulose Derivatives ◽

Asymmetric Membrane ◽

Scanning Calorimetry ◽

Water Contact ◽

Force Microscopy ◽

Cellulose Acetate Membranes ◽

High Degree

Asymmetric cellulose acetate membranes have been successfully fabricated by phase inversion, using sugarcane bagasse (SB) as the starting material. SB is a raw material with high potential to produce cellulose derivatives due to its structure and morphology. Cellulose was extracted from SB by pretreatment with solutions of 5 wt% NaOH, 0.5 wt% EDTA; then bleached with 2 wt% H2O2. Cellulose acetate (CA) was prepared by the reaction between extracted cellulose with acetic anhydride, and H2SO4 as a catalyst. The obtained CA exhibited a high degree of substitution (2.81), determined with 1H-NMR spectroscopy and titration. The functional groups and thermal analysis of the extracted cellulose and the synthesized CA have been investigated by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The change in the crystallinity of the extracted cellulose and CA was evaluated by X-ray diffraction (XRD) spectroscopy. Asymmetric membranes were fabricated using dimethyl sulfoxide (DMSO) as the solvent, with a casting thickness of 250 µm. The obtained membranes were studied by scanning electron microscopy (SEM), DSC and atomic force microscopy (AFM). The hydrophilicity of the membranes was evaluated, as demonstrated by the measurement of water contact angle (WCA) and water content. Furthermore, the antifouling properties of membranes were also investigated.

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Study of Polymorphs of Zirconia in the System ZrO2: ƞ wt% Re2O3 Obtained by Polymeric Precursor Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1340 ◽

2012 ◽

Vol 727-728 ◽

pp. 1340-1344

Author(s):

R.A. Muñoz ◽

J.E. Rodriguez ◽

Cosme Roberto Moreira Silva

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Zirconium Oxide ◽

Pechini Method ◽

Synthesis Method ◽

Raw Material ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Dysprosium Oxide ◽

Transmission Electron

In this paper we propose the stabilization of zirconium oxide with controlled additions of a rare earth elements concentrate, in the system ZrO2: ƞ wt% Re2O3 (withƞ=5.36, 10.47, 13.74, 16.91 e 20) whereRe2O3is a rare earth elements concentrate composed mainly of 76.88% of yttrium oxide, 12.1% of Dysprosium oxide, 4.04% of Erbium oxide and 1.94% of Holmium oxide. The synthesis method used was the Pechini method. The results show that additions of 5.36 and 20 wt% of the concentrate are enough to stabilize the tetragonal and cubic zirconia phases respectively, and that zirconium oxide polymorphs can coexist with additions within these limit. In the characterization of the obtained powders are presented and discussed the following results: differential scanning calorimetry, transmission electron microscopy and X-ray diffraction. Also, it was necessary to make analysis by Rietveld refinement because they had severe overlap in the diffraction peaks. One of the most relevant results is obtaining a raw material, cheap to be used in many technological applications.

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Formation of Rutin–β-Cyclodextrin Inclusion Complexes by Supercritical Antisolvent Precipitation

Polymers ◽

10.3390/polym13020246 ◽

2021 ◽

Vol 13 (2) ◽

pp. 246

Author(s):

Paola Franco ◽

Iolanda De Marco

Keyword(s):

Inclusion Complexes ◽

Point Of View ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Cyclodextrin Inclusion Complexes ◽

Antisolvent Precipitation ◽

Supercritical Antisolvent ◽

Dissolution Tests ◽

Vis Spectroscopy ◽

Supercritical Antisolvent Precipitation

In this work, rutin (RUT)–β-cyclodextrin (β-CD) inclusion complexes are prepared by Supercritical AntiSolvent (SAS) precipitation. Well-defined composite microparticles are obtained at guest:host ratios equal to 1:2 and 1:1 mol:mol. The dimensions of composite particles range between 1.45 ± 0.88 µm and 7.94 ± 2.12 µm. The formation of RUT–β-CD inclusion complexes has been proved by different analyses, including Fourier transform infrared spectroscopy, Differential Scanning Calorimetry, X-ray diffraction, and UV-vis spectroscopy. The dissolution tests reveal a significant improvement in the release rate of RUT from inclusion complexes. Indeed, compared to the unprocessed RUT, the dissolution rate is about 3.9 and 2.4 times faster in the case of the complexes RUT–β-CD 1:2 and 1:1 mol:mol, respectively. From a pharmaceutical/nutraceutical point of view, CD-based inclusion complexes allow the reduction of the polymer amount in the SAS composite formulations.

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Extraction of Al-Si master alloy and alumina from coal fly ash

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb160616006l ◽

2017 ◽

Vol 53 (2) ◽

pp. 155-162 ◽

Cited By ~ 5

Author(s):

A. Liu ◽

Z. Shi ◽

K. Xie ◽

X. Hu ◽

B. Gao ◽

...

Keyword(s):

Fly Ash ◽

Master Alloy ◽

Power Plants ◽

Coal Fly Ash ◽

Raw Material ◽

Aluminothermic Reduction ◽

Chemical Compositions ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray

Coal fly ash from coal power plants is a potential raw material for the production of alumina. An objective aluminothermic reduction method for the preparation of Al-Si master alloy and alumina from coal fly ash was investigated. The kinetic analysis using non-isothermal differential scanning calorimetry indicated that the reduction of Al6Si2O13, Fe2O3, and TiO2 by aluminum in coal fly ash occurs at 1618 K, 1681 K, and 1754 K, respectively. Moreover, the influence of reaction temperature on product composition was studied. The phases and morphologies of the products obtained by the aluminothermic reduction of coal fly ash at 1373-1773 K were analyzed by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy, respectively. The results from X-ray diffraction show that no oxide reduction has taken place at 1373 K and 1473K, the compositions of the product obtained by aluminothermic reduction of fly ash at 1573K- 1673 K are Al2O3, mullite, Al and Si, while the compositions of the product at 1773 K are Al2O3, Al, and Si. In addition, the chemical compositions of Al-Si alloy obtained at 1773 K are 86.81 wt% Al and 13.19 wt% Si.

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N-acylhydrazone Derivative-Loaded Cellulose Acetate Films: Thermoanalytical, Spectroscopic, Mechanical and Morphological Characterization

Polymers ◽

10.3390/polym13142345 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2345

Author(s):

Amaro César Lima de Assis ◽

Lívia Maria Coelho de Carvalho Moreira ◽

Beatriz Patrício Rocha ◽

Milena Raissa Bezerra Pereira ◽

Demis Ferreira de Melo ◽

...

Keyword(s):

Cellulose Acetate ◽

Average Diameter ◽

Morphological Characterization ◽

Mechanical Tests ◽

Spectroscopic Techniques ◽

Cellulose Derivatives ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Synthetic Materials ◽

Dsc Analyses

Cellulose acetate (ACT) is one of the most important cellulose derivatives due to its biodegradability and low toxicity, presenting itself as one of the main substitutes for synthetic materials in the development of wound dressing films. The incorporation of a N-acylhydrazonic derivative (JR19), with its promising anti-inflammatory activity, may represent an alternative for the treatment of skin wounds. This work aims to develop and to physicochemically and mechanically characterize ACT films containing JR19. The films were prepared using the ‘casting’ method and further characterized by thermoanalytical and spectroscopic techniques. In addition, mechanical tests and morphological analysis were performed. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analyses showed that the thermal events attributed to excipients and films were similar, indicating the absence of physical incompatibilities between ACT and JR19. Infrared spectroscopy showed that JR19 was incorporated into ACT films. The characteristic band attributed to C≡N (2279 to 2264 cm−1) was observed in the spectra of JR19, in that of the physical mixture of JR19/ACT, and, to a lesser extent, in the spectra of JR19 incorporated into the ACT film, suggesting some interaction between JR19 and ACT. X-ray diffraction (XRD) evidenced the suppression of the crystallinity of JR19 (diffraction peaks at 8.54°, 12.80°, 14.09°, 16.08°, 18.19°, 22.65°, 23.59°, 24.53°, 25.70°, 28.16° and 30.27°2θ) after incorporation into ACT films. The mechanical tests indicated the adequate integrity of the films and their resistance to bending. The morphological characterization showed JR19 crystals along with a homogeneously distributed porous structure throughout the surface of the films with an average diameter of 21.34 µm and 22.65 µm of the films alone and of those incorporating JR19F, respectively. This study was able to characterize the ACT films incorporating JR19, showing their potential to be further developed as wound healing dressings.

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Morphology, rheology and biodegradation of oxo-degradable polypropylene/polylactide blends

Journal of Polymer Engineering ◽

10.1515/polyeng-2016-0380 ◽

2018 ◽

Vol 38 (3) ◽

pp. 239-249 ◽

Cited By ~ 8

Author(s):

Dev K. Mandal ◽

Haripada Bhunia ◽

Pramod K. Bajpai ◽

Chandrasekhar V. Chaudhari ◽

Kumar A. Dubey ◽

...

Keyword(s):

Electron Microscopy ◽

Tensile Strength ◽

Point Of View ◽

Calcium Stearate ◽

Melt Blending ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Biodegradability Test ◽

Scanning Electron

AbstractThe blends of polypropylene (PP)/polylactide (PLA) with or without compatibilizer, and with pro-oxidant (cobalt stearate/calcium stearate) and pro-oxidant filled PP were prepared by using the melt blending technique. Films of these blends were prepared by compression molding. PP85PL15 and PP85PL15MA4 were the optimum blends from the tensile strength point of view. The improvement in the tensile strength of PP85PL15MA4 blend was achieved by addition of 4 phr compatibilizer. Cobalt stearate and calcium stearate were added separately to PP85PL15MA4 blend in 0.2% (w/w) ratio. The optimized blends were further characterized by differential scanning calorimetry, X-ray diffraction, rheological studies, scanning electron microscopy (SEM) and biodegradability test. Rheological studies confirmed the pseudo-plastic nature of all the blend samples. SEM studies have revealed that the addition of PLA in PP85PL15 enhances the void and roughness on the blend. All the prepared blends have biodegraded in the composting environment and the blend containing pro-oxidant biodegraded to the maximum extent.

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Crystal forms and phase transformation of 1,5-pentanediamine-terephthalate: a bio-based nylon 5T monomer

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520620006265 ◽

2020 ◽

Vol 76 (4) ◽

pp. 524-533

Author(s):

Zihan Li ◽

Pengpeng Yang ◽

Haodong Liu ◽

Jun Liu ◽

Sha Zhu ◽

...

Keyword(s):

Transition Temperature ◽

Water Activity ◽

Raw Material ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Phase Form ◽

Crystal Forms ◽

X Ray ◽

Thermodynamic Conditions ◽

Biomass Resources

Nylon 5T is one of the bio-based nylons, its raw material 1,5-pentanediamine is derived from biomass resources and produced by biological methods. 1,5-pentanediamine-terephthalate (PDA-TPA) is the monomeric salt for nylon 5T polymerization, and its own product quality has a significant impact on the performance of nylon 5T. PDA-TPA was prepared by anti-solvent crystallization in this study. It exists in two solid forms, a monohydrate [form (I)] and an anhydrous phase [form (II)]. The transition temperature of the two phases was around 65°C in the given ethanol–water binary (7:1) mixture. The characterization of monohydrate and anhydrate phases regarding structures and stabilities was carefully carried out using powder X-ray diffraction, single crystal X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, hot-stage microscopy and Fourier transform infrared spectroscopy. The relationship between the molecular interactions of monohydrate and anhydrate phases under different packing architectures and their thermal behaviours was analysed and established. In addition, the relationships between the structures and thermal behaviours for the two solid forms were analysed and established. In addition, the effect of solvent on phase conversion, the relationships between the temperature and water activity, as well as the relative stability of monohydrate and anhydrate phases under different thermodynamic conditions, were investigated by solid–solid transformation and solvent-mediated transformation experiments. It was obvious that the transition temperature of monohydrate and anhydrate phases of PDA-TPA was significantly influenced by water activity, and the larger the value of water activity is, the higher is the transition temperature. These studies give insight into the transformation of nylon 5T monomer salt and contribute to the control of target crystal preparation.

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An Insight into the Ultrastructural and Physiochemical Characterization of Potato Starch: a Review

American Journal of Potato Research ◽

10.1007/s12230-020-09798-w ◽

2020 ◽

Vol 97 (5) ◽

pp. 464-476

Author(s):

Sreeshna Jagadeesan ◽

Indira Govindaraju ◽

Nirmal Mazumder

Keyword(s):

Potato Starch ◽

Industrial Applications ◽

Point Of View ◽

Structural Elements ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Insight Into ◽

Microscopic Techniques

Abstract Potatoes are highly consumed food around the world, usually following processing of some kind. Apart from its noteworthy presence in diets, potato starch has a multitude of industrial applications as a food additive and recently in novel domains such as nanotechnology and bioengineering. This review examines the microscopic and spectroscopic methods of characterizing potato starch and compares the different properties. The microscopic techniques such as optical microscopy and Scanning Electron Microscopy (SEM) allow observation of structural elements of potato starch. Differential Scanning Calorimetry (DSC) delves into the thermal behavior of starch in presence of water, while Fourier Transform Infrared (FTIR) spectroscopy and X-Ray Diffraction (XRD) analyze the behavior of various chemical bonds and crystallinity of starch. These characterizations are important from a dietary point of view for patients requiring a low-glycemic diet, as well as in facilitating research into a wider array of industrial applications.

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