scholarly journals PROCESSING POSSIBILITIES OF BIRCH OUTER BARK INTO GREEN BIO-COMPOSITES

Author(s):  
Aigars Paze ◽  
Janis Rizhikovs ◽  
Prans Brazdausks ◽  
Maris Puke ◽  
Juris Grinins ◽  
...  

The main objective of the study was to obtain bio-composites from grey alder sawdust using a mixture of birch outer bark suberinic acids as a binder, and to test their mechanical properties. Ethanol-extracted birch outer bark was used as a raw material for the investigation. Characteristics (suberinic acids content, epoxy acids content and acid number) of the hydrolytically depolymerized birch outer bark binder were also determined. The initial filler/binder ratio and molding parameters (temperature and pressure) were established by the full factorial design. Preliminary data showed that the increase of the pressing temperature from 160 to 200 °C at a pressure of 3.5 MPa resulted in a minor growth of the boards’ density (up to 1.0 g/cm3) and bending strength (up to 17.1 MPa). Our investigation has shown that it is possible to use one of the plywood production residues – outer birch bark – as a raw material for obtaining particleboards, which have mechanical properties beyond the standard limits. The used method is also environmentally friendly, easy realizable in practice and has a potential to be cost-effective.

2021 ◽  
Vol 903 ◽  
pp. 235-240
Author(s):  
Raimonds Makars ◽  
Daniela Godiņa ◽  
Janis Rizhikovs ◽  
Aigars Paze ◽  
Ramunas Tupciauskas ◽  
...  

Silver birch (Betula pendula) outer bark suberin can be used as a raw material to make an adhesive for particleboards (PBs). It is a promising formaldehyde-free alternative to traditional synthetic resins. However, the adhesive is acidic, which can catalyse furfural (FUR) formation from xylans in wood particles that are used for the preparation of PBs. FUR being a volatile organic compound can be emitted from the PBs and exposure to it can have harmful effects on humans. In the scope of this study, the effects on technological parameters (wet adhesive pH: 3, 6 and 9), glycerol as an additive to adhesive and hot-pressing temperature (180...230 °C) were investigated on the FUR formation in PBs. The FUR content was determined with high-performance liquid chromatography-ultraviolet spectroscopy system from the extracts of milled PBs. Mechanical properties (modulus of elasticity, bending strength, and thickness swelling) of the PBs were also studied. When using an adhesive with a pH 6 at hot-pressing temperature 230 °C with no glycerol added, it was possible to obtain PBs that satisfied the requirements of EN 312 P2 (boards for interior fitments). The FUR yield of these boards were more than 6 times lower than for the PBs pressed at 230 °C with a wet adhesive pH value 3.


2014 ◽  
Vol 92 ◽  
pp. 188-193 ◽  
Author(s):  
Tuna Aydin ◽  
Alpagut Kara

Spodumene, which is a lithium alumina silicate, has been used as a raw material in the production of thermal shock resistant whitewares and sanitarywares. The presence of spodumene results in enhancement of mullitization and imparts better physical and mechanical properties to ceramics. In this study, the influence of Lithium alumina silicate phases on the mechanical properties of standard porcelain stoneware body was investigated. Especially solid-solid reactions were observed between spodumene and quartz or spodumene and clay. These solid-solid reactions bring about a newly formed lithium alumina silicate (LAS) phases. Spodumene allows the development of a low viscosity liquid phase and results in a decrease in closed porosity, also with increase in bulk density, bending strength and elastic modulus.


2019 ◽  
Vol 70 (4) ◽  
pp. 359-367
Author(s):  
Masoud Shafie ◽  
Hamid Zarea-Hosseinabadi

This study was performed to use date palm rachis, as a low value bio-waste, in the manufacture of a high value added eco-friendly structural composite lumber. Taguchi design of experiments was applied to analyse the effect of raw material and product parameters on the mechanical properties of laminated strand lumber from date palm rachis. The results indicate that the composite exhibits similar or superior strength properties compared to solid lumber and engineered products from wood or other lignocellulosic material for building sector. Taguchi design of experiments was assessed as a powerful and cost effective technique to obtain optimal levels for maximizing the mechanical properties of the environmentally-friendly composite. Maximum values for the mechanical properties of date palm rachis-based LSL were obtained from a combination of 20 mm product thickness, 10 % resin content, 4mm strand thickness, and 850 kg/m3 product density. Product thickness with an 81.3 % contribution and strand thickness with an 80 % contribution have the highest effects on the flatwise stiffness and compression strength perpendicular to grain, respectively.


2020 ◽  
Vol 841 ◽  
pp. 254-258
Author(s):  
Yustiasih Purwaningrum ◽  
Muhammad Hafiz ◽  
Risky Suparyanto

Buckets are the most important component in backhoe construction, the bucket functions as a digger and carrier component in an excavator. Due to the heavy working media of the excavator so that this component is the most easily damaged part, damage that often occurs is wear caused by friction arising so that the thickness of the bucket is reduced which can eventually cause cracks in the bucket and in continuous use can cause the bucket to crack and broken. Cladding method is done to shorten the time or simplify the repair process is to directly patch the damaged part with a welding layer and then do the grading using a grinding. This study aims to determine the physical and mechanical properties of the material from the cladding process when compared with the raw material, the variations used are raw material, cladding with filler welding, and cladding with plates. The welding process is carried out with GMAW (Gas Metal Arc Welding) and low carbon steel. Welding results will be tested tensile strength, bending strength , impact test, hardness test, chemical composition, and corrosion rate. From the hardness test results showed that the weld metal from plate variation has the highest hardness value of 443 VHN. From the results of tensile testing the basic material has the highest value with 359.08 MPa. From the bending test results the highest value obtained from filler verification with 494.01 Mpa and the highest impact price obtained from the plate variation cladding method with a value of 1.49 J / mm2


Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4380
Author(s):  
Janis Rizikovs ◽  
Daniela Godina ◽  
Raimonds Makars ◽  
Aigars Paze ◽  
Arnis Abolins ◽  
...  

Global sustainability challenges prompt the world to modify its strategies and shift from a fossil-fuel-based economy to a bio-resources-based one and to the production of renewable biomass chemicals. Depolymerized suberinic acids (SA) were considered as an alternative resource to develop bio-polyols that can be further used in polyurethane (PU) material production. Birch (Betula pendula) outer bark was used as a raw material to obtain the SA, extracted with ethanol, and depolymerized with potassium hydroxide ethanol solution. By acidifying the filtrate to pH 5.0, 3.0, and 1.0 and drying it at 50 °C and 130 °C, 12 different SA potential feedstocks were obtained and characterized using chemical (total phenolics content, solubility in DMSO, acid, hydroxyl, and saponification number) and instrumental analytical methods (GC-MS, SEC-RID, DSC, and FTIR). Several bio-polyols were synthesized from the SA sample acidified to pH 1 and dried at 130 °C. Acid number and hydroxyl number values, the apparent viscosity and moisture content were measured. It was concluded that SA have a high enough saponification and acid value to investigate the polyol synthesis route via the esterification reaction. Moreover, SA had OH groups in their structure, which can be exploited for PU material development. The majority of SA compounds had relatively low molecular weight with <1300 Da that are suited for bio-polyol synthesis applied for rigid PU foam development. The synthesized bio-polyols had high hydroxyl number values necessary for bio-polyols to be used for rigid PU foam production.


2007 ◽  
Vol 352 ◽  
pp. 185-188 ◽  
Author(s):  
Toru Wakihara ◽  
Masahiro Yabuki ◽  
Junichi Tatami ◽  
Katsutoshi Komeya ◽  
Takeshi Meguro ◽  
...  

Post-reaction sintering as a technique for the fabrication of Si3N4 ceramics has received much attention as a cost-effective process due to the use of cheap Si powder as a raw material. In this method, the rapid exothermic nitridation of Si results in local melting of Si to cause its agglomeration, which is expected to be a flaw after densification. Therefore, control of the exothermic reaction is needed to improve the reliability of post-reaction sintered Si3N4 ceramics. In this study, Si3N4 ceramics were fabricated by post-reaction sintering with Si3N4 or SiO2 powders in order to control the exothermic reaction. As a result, the microstructure and bending strength of Si3N4 ceramics was changed by adding these additives. In particular, the addition of SiO2 resulted in the high strength of Si3N4 ceramics. Consequently, it was found that Si3N4 and SiO2 particles played the role of diluents, and SiO2 was effective in post-reaction sintering as an oxygen donor.


2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Oghenekevwe Abigail Ohwo ◽  
Ighoyivwi Onakpoma ◽  
Eduvie Okoromaraye

Reuse of materials from waste streams is pertinent to achieving sustainable forest production. The enormous wood residues generated at sawmill and the disposal of wood based products poses threat not only to sustenance of the forest resources but also has negative adverse effect on the environment. Limitation exists in the utilization of wood residues as raw material for panel board production in developing countries. This study examined the physical and mechanical properties of graded density fiberboards produced from varying mixture of sawdust and corrugated paper (pulp) at Forestry Research Institute of Nigeria (FRIN) in 2019. A 2x9 factorial experiment in one way analysis of variance was used to test for significant difference between the factors (density and mixing ratio) considered. The result shows that densities of all boards produced varied with mixing proportions. The densities increased with increasing content of corrugated paper. Boards produced at 0.45 g/cm3 showed higher density (0.648 g/cm3), bending strength (MOR) (1.47 N/mm2) and less water absorption (118.69 %) than those produced at 0.65 g/cm3 having values of 0.58 g/cm3, 1.32 N/mm2 and 153.67 %  respectively. However boards produced at 0.65 g/cm3 had higher elasticity in bending (MOE) (209.19 N/mm2) and less thickness swelling (6.29 %) than those produced at 0.45 g/cm3 having values of 74.87 N/mm2 and 10.88% respectively. Panel G (20:60:20), E (30:50:20) and I (10:70:20) of sawdust: corrugated paper: urea formaldehyde respectively showed superior features in physical and mechanical properties with panel I been the best mixture. Conclusively, wood residues (sawdust and corrugated paper) are suitable raw material for fiberboard production.


2016 ◽  
Vol 16 (1) ◽  
pp. 17-26
Author(s):  
M. Gajek ◽  
A. Rapacz-Kmita ◽  
M. Dudek ◽  
J. Partyka

Abstract The article presents results of research on microstructural and mechanical properties of floor tiles clinker manufactured on the basis of Wierzbka I raw material, which is part of the deposit Wierzbka, near Suchedniów. Wierzbka I clay was added in various volume fractions to the standard tile compositions used in industrial practice. The samples were pressed in a range of from 21 MPa to 42 MPa and fired in the laboratory furnace at 1130°C to 1190°C. Selected compositions were pressed at 28 MPa and fired in a standard industrial environment. The process of firing was conducted in an industrial kiln at temperature of 1160°C for 38 minutes, with holding for 4 minutes at maximum operating temperature. The samples, which were prepared in the laboratory and industrial conditions were evaluated for the effect of addition of the Wierzbka I clay on their microstructural and mechanical properties based on the measurement results of linear shrinkage, bulk density, open porosity, water absorption and flexural strength (Ϭ) of the tiles. Microstructural changes were observed with a scanning electron microscope (SEM). The results revealed that the tested tiles were characterized by a high degree of sintering, an apparent density of 2.5 g/cm3, an open porosity and water absorption below 0.5%. The measurement results of mechanical bending strength showed that the tested samples had a high strength of 50 MPa.


2016 ◽  
Vol 9 (1) ◽  
pp. 80-95
Author(s):  
Agus Sudibyo ◽  
Sardjono Sardjono

Crude palm oil (CPO)is the richest natural plant source of carotenoids in terms of retinol (pro-vitamin A) equivalent, whereas palm oil mill effluent (POME) is generated from palm oil industry that contains oil and carotenes that used to be treated before discharge. Carotenoids are importance in animals and humans for the purpose of the enhancement of immune response, conversion of vitamin A and scavenging of oxygen radicals. This component has different nutritional  functions and benefits to humaan health. The growing interest in the other natural sources of beta-carotene and growing awareness to prevent pollution has stimulated the industrial use of CPO and POME as a raw material for carotenoids extraction. Various technologies of extraction and separation have been developed in order to recover of carotenoids.This article reports on various technologies that have been developed in order to recover of carotenoids from being destroyed in commercial refining of palm oil and effects of some various treatments on the extraction end separation for carotenoid from palm oil and carotenoids concentration. Principally, there are different technologies, and there is one some future which is the use of solvent. Solvent plays important role  in the most technologiest, however the problem of solvents which are used is that they posses potentiaal fire health and environmental hazards. Hence selection of the  most safe, environmentally friendly and cost effective solvent is important to design of alternative extraction methods.Chemical molecular product design is one of the methods that are becoming more popular nowadays for finding solvent with the desired properties prior to experimental testing.ABSTRAKMinyak sawit kasar merupakan sumber karotenoid terkaya yang berasal dari tanaman sawit sebagai senyawa yang sama dengan retinol atau pro-vitamin A; sedangkan limbah pengolahan minyak sawit dihasilkan dari industri pengolahan minyak sawit yang berisi minyak dan karotene yang perlu diberi perlakuan terlebih dahulu sebelum dibuang. Karotenoid merupakan bahan penting yang diperlukan pada hewan dan manusia guna memperkuat tanggapan terhadap kekebalan, konversi ke vitamin A dan penangkapan gugus oksigen radikal. Dengan berkembangnya ketertarikan dalam mencari beta-karotene yang bersumber dari alam lain dan meningkatnya kesadaran untuk mencegah adanya pencemaran lingkungan, maka mendorong suatu industri untuk menggunakan CPO dan POME sebagai bahan baku untuk diekstrak karotenoidnya. Berbagai macam teknologi guna mengekstrak dan memisahkan karotenoid telah dikembangkan untuk mendapatkan kembali karotenoidnya. Makalah ini melaporkan dan membahas berbagai jenis teknologi yang telah dikembangkan guna mendapatkan kembali senyawa karotenoid dari kerusakan di dalam proses pemurnian minyak sawit secara komersial dan pengaruh beberapa perlakuan terhadap ekstrasi dan pemisahan karotenoid dari minyak sawit dan konsentrasi karotenoidnya. Pada prinsipnya, berbagai teknologi yang digunakan untuk mengekstrak dan memisahkan karotenoid terdapat perbedaan, dan terdapat salah satu teknologi yang digunakan untuk esktrasi dan pemisahan karotenoid adalah menggunakan bahan pelarut. Pelarut yang digunakan mempunyai peranan yang penting dalam teknologi ekstrasi; namun pelarut yang digunakan untuk mengekstrak tersebut mempunyai persoalan karena berpotensi mengganggu kesehatan dan membahayakan cemaran lingkungan. Oleh karena itu, pemilihan jenis teknologi yang aman, ramah terhadap lingkungan dan biaya yang efektif untuk penggunaan pelarut merupakan hal penting sebelum dilakukan desain metode/teknologi alternatif untuk esktrasi karotenoid. Pola produk molekuler kimia merupakan salah satu metode yang saat ini menjadi lebih populer untuk mencari pelarut dengan sifat-sifat yang dikehendaki sebelum diujicobakan. Kata kunci :    karotenoid, ekstrasi, pemisahan, teknologi, minyak sawit kasar, limbah industri pengolahan sawit.


2020 ◽  
pp. 39-48
Author(s):  
B. O. Bolshakov ◽  
◽  
R. F. Galiakbarov ◽  
A. M. Smyslov ◽  
◽  
...  

The results of the research of structure and properties of a composite compact from 13 Cr – 2 Мо and BN powders depending on the concentration of boron nitride are provided. It is shown that adding boron nitride in an amount of more than 2% by weight of the charge mixture leads to the formation of extended grain boundary porosity and finely dispersed BN layers in the structure, which provides a high level of wearing properties of the material. The effect of boron nitride concentration on physical and mechanical properties is determined. It was found that the introduction of a small amount of BN (up to 2 % by weight) into the compacts leads to an increase in plasticity, bending strength, and toughness by reducing the friction forces between the metal powder particles during pressing and a more complete grain boundary diffusion process during sintering. The formation of a regulated structure-phase composition of powder compacts of 13 Cr – 2 Mо – BN when the content of boron nitride changes in them allows us to provide the specified physical and mechanical properties in a wide range. The obtained results of studies of the physical and mechanical characteristics of the developed material allow us to reasonably choose the necessary composition of the powder compact for sealing structures of the flow part of steam turbines, depending on their operating conditions.


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