scholarly journals Impact of Lignin Content on the Properties of Hemicellulose Hydrogels

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 35 ◽  
Author(s):  
Basel Al-Rudainy ◽  
Mats Galbe ◽  
Monica Arcos Hernandez ◽  
Patric Jannasch ◽  
Ola Wallberg
Keyword(s):  
Membrane Filtration ◽  
Lignin Content ◽  
Chemical Properties ◽  
Downstream Processing ◽  
Raw Material ◽  
Crosslinking Reaction ◽  
Waste Streams ◽  
Renewable Raw Material ◽  
Effect Of Impurities ◽  
And Chemical Properties

Hemicellulose is a promising renewable raw material for the production of hydrogels. This polysaccharide exists in large amounts in various waste streams, in which they are usually impure and heavily diluted. Several downstream processing methods can be combined to concentrate and purify the hemicellulose. However, such an approach can be costly; hence, the effect of impurities on the formation and properties of hydrogels must be determined. Lignin usually exists in these waste streams as a major impurity that is also difficult to separate. This compound can darken hydrogels and decrease their swellability and reactivity, as shown in many studies. Other properties and effects of lignin impurities are equally important for the end application of hydrogels and the overall process economy. In this work, we examined the feasibility of producing hydrogels from hemicelluloses that originated from sodium-based spent sulfite liquor. A combination of membrane filtration and anti-solvent precipitation was used to extract and purify various components. The influence of the purity of hemicellulose and the addition of lignosulfonates (emulated impurities in the downstream processing) to the crosslinking reaction mixture on the mechanical, thermal, and chemical properties of hydrogels was determined.

scholarly journals A genetic base of utilisation of maize cob as a valuable naturally renewable raw material

Genetika ◽  
2004 ◽  
Vol 36 (3) ◽  
pp. 245-256 ◽  
Author(s):  
Irina Bozovic ◽  
Milica Radosavljevic ◽  
Sladjana Zilic ◽  
Rade Jovanovic
Keyword(s):  
Chemical Properties ◽  
Raw Material ◽  
Particle Sizes ◽  
Great Capacity ◽  
Renewable Raw Material ◽  
Maize Cob ◽  
Metal Processing Industry ◽  
Physical And Chemical ◽  
Maize Research Institute ◽  
And Chemical Properties

The original technological method of the maize cob processing has been developed at the Maize Research Institute, Zemun Polje, by which lignocellulose granules of different particle sizes are produced from the cob. Different chemical composition and physical and chemical properties of these fractions, and especially a great capacity of binding liquids particularly oil and water determine, their usage as degreasing and drying means. Due to their great hardness and abrasive capacity, products made from ground cobs are usable for polishing in the metal processing industry, while the composition of certain compounds (pento-san) are of a particular importance in the chemical industry for the pro duction of furfural and its derivates. As these products are inert, of neutral pH and free of heavy metals they are used as organic carriers in the pro duction of pesticides and agro-chemicals, as well as, in cosmetics and the pharmaceutical industry.

Effects of Gamma Irradiation Upon the Mechanical and Chemical Properties of 3D-Printed Samples of Polylactic Acid

2019 ◽  
Vol 141 (4) ◽  
Author(s):  
Conrad West ◽  
Robert McTaggart ◽  
Todd Letcher ◽  
Douglas Raynie ◽  
Ranen Roy
Keyword(s):  
Polylactic Acid ◽  
Chemical Properties ◽  
Waste Streams ◽  
Exponential Functions ◽  
Destructive Testing ◽  
Space Applications ◽  
Mechanical Responses ◽  
Decomposition Processes ◽  
3D Printed ◽  
And Chemical Properties

3D printing offers the opportunity to design and make replacement parts to exacting specifications when needed. This is particularly helpful for space applications where stand-alone replacement mechanisms are required. Samples of 3D-printed polylactic acid (PLA) were subjected with up to 200 kGy of gamma radiation from a Cobalt-60 irradiator. The mechanical responses to destructive testing were successfully modeled with a combination of linear and exponential functions and may be understood given the underlying chemical changes due to said radiation exposures. We find that for doses up to 50 kGy, the performance of 3D-printed PLA is largely unaffected, which is beneficial for applications in space and in medicine. At larger doses, it appears that decomposition processes win out over cross-linking, which may aid in the degradation of PLA in waste streams.

Sugarcane Biochar for Agricultural Use Produced in Different Conditions of Pyrolysis

2019 ◽  
pp. 1-8
Author(s):  
Juliany Barbosa de Pinho ◽  
Aloisio Bianchini ◽  
Pedro Silvério Xavier Pereira ◽  
Letycia Cunha Nunes ◽  
Rodrigo Fernandes Daros ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Exchange Capacity ◽  
Raw Material ◽  
Physical And Chemical Properties ◽  
Oxidizing Atmosphere ◽  
Different Temperatures ◽  
Agricultural Use ◽  
Physical And Chemical ◽  
And Chemical Properties

From the pyrolysis process, biochar is a carbon rich and recalcitrant organic material with potential for long term carbon sequestration because of its aromatic structure. However, the physical and chemical properties of the biochar vary due to the diversity of raw material and the conditions of production. The present study aimed to evaluate the biochar from the sugarcane bagasse at different temperatures and under two conditions of pyrolysis. The biochar was produced at two final temperatures 200°C (1 hour); 250°C (1h) and 250°C (2h), with pyrolysis of an oxidizing and non-oxidizing atmosphere for both. PH, cation exchange capacity (CTC), carbon content (C), Nitrogen (N), hydrogen (H), H:C, C:N and ash ratios were evaluated. The contents of C, H, N and the atomic ratios H:C and C:N were higher in Biochar produced in a non-oxidizing atmosphere (BNO). However, the content of ash, pH and CTC were higher in Biochar produced in oxidizing atmospheres (BO). One can conclude the direct influence of the pyrolysis condition.

scholarly journals Technological Parameters of the Process of Producing Metallized Iron Concentrates from Poor Raw Material

2019 ◽  
Vol 8 (11) ◽  
pp. 600-603 ◽  
Keyword(s):  
Chemical Properties ◽  
Raw Material ◽  
Physical And Chemical Properties ◽  
Technological Parameters ◽  
Metallurgical Processing ◽  
Physical And Chemical ◽  
And Chemical Properties

In article the possibility of receiving the metallized concentrates from ferriferous ores with the low content of iron, for the purpose of preparation them to metallurgical processing is considered. It is shown that the following factors have significant effect on effectiveness of process of receiving the metallized concentrates: composition of ore, physical and chemical properties of ore, possibility of receiving pellets, type and consumption of reducer, etc.

scholarly journals Study of Microstructural and Corrosion Properties of Aluminium Alloy 7075 after Plasma Nitriding

2020 ◽  
Vol 21 (1) ◽  
pp. 1
Author(s):  
Haerul Ahmadi ◽  
Rizky Abdul Aziz ◽  
Suprapto Suprapto ◽  
Tjipto Sujitno ◽  
Sophie Hapsari
Keyword(s):  
Aluminium Alloy ◽  
Plasma Nitriding ◽  
White Layer ◽  
Chemical Properties ◽  
Electrochemical Corrosion ◽  
Corrosion Testing ◽  
Raw Material ◽  
Corrosion Properties ◽  
Structural Part ◽  
And Chemical Properties

Plasma nitriding is a treatment process of metals by depositing nitrogen into metal that considered to be nitrided by mean of increasing the mechanical, physical, and chemical properties of the metal. This treatment will form a hard layer compund of Al-N on the surface of the sample. In this study, aluminium alloy 7075 was nitrided which the application of it to structural part of aircraft makes it vulnarable to not only corrosion and wear attack but also decreasing the hardness of the material. One method to overcome these issues is plasma nitriding. The purpose of of this research is to do the characterizations of plasma nitrided aluminium alloy 7075 regarding its microstructure, mechanical, and chemical properties. The characterizations that had been done were microhardness Vickers testing, SEM-EDX, and electrochemical corrosion testing Potensiostat. The hardness of the sample increased 55% from 75,88 VHN (raw material) to 117,68 VHN (at optimum parameter). The depth of the white layer of plasma nitriding is approximately 6 µm, while the EDX result reported carbon, oxygen, and nitrogen presence. Corrosion testing showed that the highest corrosion rate is on the raw material, 0,15393 mpy. While the optimum one is 0,07184 mpy.

scholarly journals Effect of Li, Na and K Modification of Alumina on its Physical and Chemical Properties and Water Adsorption Ability

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4212 ◽  
Author(s):  
Sergey Reshetnikov ◽  
Irina Kurzina ◽  
Alesia Livanova ◽  
Eugene Meshcheryakov ◽  
Lyubov Isupova
Keyword(s):  
Low Temperature ◽  
Water Adsorption ◽  
Chemical Properties ◽  
Raw Material ◽  
Physical And Chemical Properties ◽  
High Adsorption ◽  
Initial Sample ◽  
Adsorption Ability ◽  
Physical And Chemical ◽  
And Chemical Properties

The effect of alkali metal (Li, Na, K) incorporation on the morphology and water vapor uptake properties of mesoporous Al2O3 has been studied. The modification of the raw material, pseudoboehmite, represented a mixture of low-temperature phases (γ + η + χ)-Al2O3, and has been done at low-temperature that does not change the phase ratio. A decrease in specific surface values and an average pores size increase were observed as a result of the introduction of metal cations by impregnation and subsequent thermal treatment. The influence of the content of the modifying metal on the adsorption ability of the obtained samples in relation to water vapours has been studied. It has been established that alkaline modification Al2O3 with the lithium cations did not result in adsorption ability improvement, whereas samples that were modified with sodium or potassium in the amount of 1.2 weight % and 2.6 weight %, respectively, possess a higher equilibrium capacity (by ~40%), as compared to that of the initial sample (Al2O3), and a sufficiently high adsorption rate.

scholarly journals Pengaruh Proses Refining Minyak Bekas Sebagai Bahan Baku Biodiesel

2018 ◽  
Vol 11 (2) ◽  
pp. 72
Author(s):  
Ni Made Suaniti ◽  
I Wayan Bandem Adnyana
Keyword(s):  
Sulfuric Acid ◽  
Chemical Properties ◽  
Frying Oil ◽  
Raw Material ◽  
Infrared Analysis ◽  
Used Oil ◽  
Wave Numbers ◽  
Homogeneous Particle ◽  
Physical And Chemical ◽  
And Chemical Properties

Penampakan minyak bekas hasil penggorengan yang berwarna coklat gelap tidak baik dikonsumsi akibat sifat fisik dan kimia minyak berubah sehingga dapat dimanfaatkan sebagai bahan bakar atau biodiesel. Tujuan penelitian ini adalah menganalisis bahan baku minyak hasil penggorengan setelah direfining dengan asam sulfat dan biodiesel hasil proses transesterifikasi dengan CaO sebagai katalis heterogen. Metode yang digunakan adalah spektroskopi Infra merah dan pengukuran secara mikroskopik. Hasil refining minyak bekas dengan asam sulfat lebih jernih dan analisis secara Infra Merah menunjukkan bahwa terjadi penurunan serapan pada berbagai bilangan gelombang dibandingkan terhadap minyak bekas. Serapan terjadi pada bilangan gelombang 2900 cm-1 diduga adanya ikatan –CH3, -CH2-, -C-H; 1656 cm1 diduga adalah ikatan C=C dan C=O; 1300 cm-1 diduga ikatan–C-H; dan 3600 cm-1 diduga adanya ikatan O-H. Secara mikroskopik menunjukkan hasil dengan ukuran partikel semakin kecil dan lebih homogen. The appearance of dark brown frying oil that is used for frying is not well consumed due to the changing physical and chemical properties of the oil so that it can be used as fuel or biodiesel. The aim of this study was to analyze the raw material of frying oil after being refined with sulfuric acid and biodiesel from the transesterification process with CaO as a heterogeneous catalyst. The method used is infrared spectroscopy and microscopic measurements. The results of refining used oil with sulfuric acid became clear and infrared analysis showed that there was a decrease in absorption at various wave numbers compared to used oil. Absorption occurred at wave numbers 2900 cm-1 was suspected to have –CH3, -CH2-, C-H bonds; 1656 cm-1 was thought to be C=C and C=O bonds; 1300cm-1  was –C-H bond;  and 3600 cm-1 was suspected to be O-H bond. Microscopically shows the results with smaller and more homogeneous particle sizes.

Synthesis of Lignin-Based Polyurethanes: A Mini-Review

2019 ◽  
Vol 16 (4) ◽  
pp. 345-352 ◽  
Author(s):  
Júlia Rocha Gouveia ◽  
Cleber Lucius da Costa ◽  
Lara Basílio Tavares ◽  
Demetrio Jackson dos Santos
Keyword(s):  
Lignin Content ◽  
Thermoplastic Polyurethane ◽  
Value Added ◽  
Raw Material ◽  
Hydroxyl Groups ◽  
A Value ◽  
Reactive Groups ◽  
Potential Applications ◽  
Renewable Raw Material ◽  
Direct Incorporation

Lignin is a natural polymer composed primarily of phenylpropanoid structures with an abundance of reactive groups: aliphatic and aromatic hydroxyls, phenols, and carbonyls. Considering the large quantity of hydroxyl groups, lignin has significant potential as a replacement for petroleum-based polyols in polyurethane (PU) synthesis and as a value-added, renewable raw material for this purpose. Several methods of lignin-based polyurethane synthesis are reviewed in this paper for reactive and thermoplastic systems: direct lignin incorporation, chemical lignin modification and depolymerization. Despite the unmodified lignin low reactivity towards diisocyanates, its direct incorporation as polyol generates highly brittle PUs, but with proper performance when applied as adhesive for wood. PU brittleness can be reduced employing polyols obtained from lignin/chain extender blends, in which glass transition temperature (Tg), mechanical properties and PU homogeneity are strongly affected by lignin content. The potential applications of lignin can be enhanced by lignin chemical modifications, including oxyalkylation and depolymerization, improving polyurethanes properties. Another PU category, lignin- based thermoplastic polyurethane (LTPU) synthesis, emerges as a sustainable alternative and is also presented in this work.

scholarly journals Synthesis and Characterization of Porous CaCO3 Vaterite Particles by Simple Solution Method

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4425
Author(s):  
Renny Febrida ◽  
Arief Cahyanto ◽  
Ellyza Herda ◽  
Vanitha Muthukanan ◽  
Nina Djustiana ◽  
...  
Keyword(s):  
Reaction Time ◽  
Reaction Times ◽  
Chemical Properties ◽  
Raw Material ◽  
Porous Microsphere ◽  
Different Temperatures ◽  
Mixing Method ◽  
Physical And Chemical ◽  
And Chemical Properties

Appropriately engineered CaCO3 vaterite has interesting properties such as biodegradability, large surface area, and unique physical and chemical properties that allow a variety of uses in medical applications, mainly in dental material as the scaffold. In this paper, we report the synthesis of vaterite from Ca(NO3)2·4H2O without porogen to obtain a highly pure and porous microsphere for raw material of calcium phosphate as the scaffold in our future development. CaCO3 properties were investigated at two different temperatures (20 and 27 °C) and stirring speeds (800 and 1000 rpm) and at various reaction times (5, 10, 15, 30, and 60 min). The as-prepared porous CaCO3 powders were characterized by FTIR, XRD, SEM, TEM, and BET methods. The results showed that vaterite with purity 95.3%, crystallite size 23.91 nm, and porous microsphere with lowest pore diameter 3.5578 nm was obtained at reaction time 30 min, temperature reaction 20 °C, and stirring speed 800 rpm. It was emphasized that a more spherical microsphere with a smaller size and nanostructure contained multiple primary nanoparticles received at a lower stirring speed (800 rpm) at the reaction time of 30 min. One of the outstanding results of this study is the formation of the porous vaterite microsphere with a pore size of ~3.55 nm without any additional porogen or template by using a simple mixing method.

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