Study of an Appropriate Suberinic Acids Binder for Manufacturing of Plywood

2019 ◽  
Vol 800 ◽  
pp. 251-255
Author(s):  
Aigars Paze ◽  
Janis Rizhikovs

In the study, birch outer bark`s suberinic acids (SA), appropriate for binding the plywood, obtained in a water medium and precipitated in two acidification stages under various medium pH levels, were characterized, which could become a sustainable, environmentally friendly alternative to toxic, formaldehyde-containing plywood binders. In the process of obtaining SA, it was found that all SA of the first acidification stage filtrated successfully. With increasing the pH level of precipitation from 2 to 6, the yield of SA decreased from 35.6 to 18.8 wt% from oven dry (o.d.) extracted birch outer bark or 69.5-36.6 wt% from total o.d. raw material SA. Meanwhile, only one sample of SA from the second acidification stage with the initial pH level 6 filtrated successfully, reaching the yield of 4.4 wt% from total o.d. raw material SA. The SA obtained in the first acidification stage at the pH level 2 contained a lower amount of epoxy groups – 1.7 wt% from o.d. SA, but at the same time, the highest acid value – 84.4 mg KOH/g. In turn, increasing the pH level to 6, the amount of epoxy groups increased gradually up to 19.9 wt% from o.d. SA, and the acid value of SA decreased to 67.4 mg KOH/g. The acid value of SA from the second acidification stage was 133.0 mg KOH/g, but epoxy groups in the composition were not observed.

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.


2012 ◽  
Vol 1 (1) ◽  
pp. 38-44
Author(s):  
Michael Lim ◽  
Eric Wirtanto ◽  
Zuhrina Masyithah

Indonesia as one of the biggest producer of crude palm oil in the world for sure will have some problems on handling their wastes such as palm shell. Palm shell is one of industrial wastes that having low commercial value with contain about 29,4 % lignin component which very potential for  use as new raw material for Sodium LignoSulfonat production. Sodium lignosulphonate (SLS) is a product of isolated lignin sulphonation process using NaHSO3 as sulphonation agent.The research begins with isolated lignin from palm shell amd continued with sulphonation with mass ratio of palm shell lignin – NaHSO3(b/b) of 1:0.2, 1:0.3, and 1:0.5 and initial pH of 6,7 and  8  at temperature 85 oC and 95 oC. Studies on the efeect of various ratio of palm shell lignin – NaHSO3 and initial pH and temperature for the sulphonation raction showed an increasing yield  of (SLS) yield. The highest SLS yield of 51,2 % was obtained under condition mass ratio of palm shell lignin – NaHSO3 1:0.3, pH 7 and at temperature 95 oC. The resulted SLS was dark brown, purity 66,1782, pH level between 6-7, water soluble.


2021 ◽  
Vol 410 ◽  
pp. 411-417
Author(s):  
Anastasia A. Zvereva ◽  
Vladimir A. Shunin ◽  
Roman S. Voinkov ◽  
Konstantin L. Timofeev

The article lays out the findings aimed to develop the fine silver powder production technique for electronics industry by selecting the variable parameters whereby a number of powder grades can be produced in the existing production environment (JSC “Uralelektromed”, Russia). The tests for significance of the parameters of silver recovery by ascorbic acid such as pH level of nitrate silver solution, dispersant flow rate, initial concentration of silver, mixing rate and solution temperature made it possible to choose optimum conditions to produce powders of 0.8-6.3 μm in particle size, of 3.0-4.2 g/cm3 in tapped density and with the specific surface area of 2300-4300 cm2/g. Crystalline silver of 99.98 % purity served as a raw material for obtaining silver powders.


Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 527 ◽  
Author(s):  
Gaojian Ma ◽  
Lingmei Dai ◽  
Dehua Liu ◽  
Wei Du

Acidic oil, which is easily obtained and with lower cost, is a potential raw material for biodiesel production. Apart from containing large quantity of FFAs (free fatty acids), acidic oil usually contains some amount of inorganic acid, glycerides and some other complex components, leading to complicated effect on lipase’s catalytic performance. Exploring the efficient process of converting acidic oil for biodiesel production is of great significance to promote the use of acidic oil. A two-step conversion process for acidic soybean oil was proposed in this paper, where sulfuric acid-mediated hydrolysis was adopted first, then the hydrolyzed free fatty acid, collected from the upper oil layer was further subject to the second-step esterification catalyzed by immobilized lipase Novozym435. Through this novel process, the negative effect caused by harmful impurities and by-product glycerol on lipase was eliminated. A fatty acid methyl ester (FAME) yield of 95% could be obtained with the acid value decreased to 4 mgKOH/g from 188 mgKOH/g. There was no obvious loss in lipase’s activity and a FAME yield of 90% could be maintained with the lipase being repeatedly used for 10 batches. This process was found to have a good applicability to different acidic oils, indicating it has great prospect for converting low quality oil sources for biodiesel preparation.


REAKTOR ◽  
2017 ◽  
Vol 5 (2) ◽  
pp. 79
Author(s):  
Abdullah Abdullah ◽  
H. B. Mat

The liquid pineapple waste contain mainly sucrose, glucose, fructose, and other nutrients. It therefore can potentiall be used as carbon source for organic acid fermentation. Recently, lactic acid has been considered to be an important raw material for production of biodegradadable lactace polymer. The experiments weree carried out in shake flash fermentation using lactobacillus delbroeckii. Effect of some parameters such as temperature, initial Ph, initial substrate concentration, yeast extract concentration and fermentation time to the yield have been studied. The highest yield was 85.65% achieved at 40 0C, PH 6.00, 52.2 g/l sugar concentration with 5 g/l yeast extract. There was no significant increasing in lactic acid production was observed if supplementation of yeast extract above 10%.Keyword : lactic acid fermentation, liquid pineapple waste, lactobacillus delbrueckii


2018 ◽  
Vol 78 (4) ◽  
pp. 764-775 ◽  
Author(s):  
Agnieszka Ryznar-Luty ◽  
Edmund Cibis ◽  
Krzysztof Lutosławski

Abstract The aim of the study was to examine how temperature and the pH influence the progress and efficiency of an aerobic biodegradation process, where major organic pollutants are removed from beet molasses vinasse by a mixed culture of Bacillus bacteria. It was conducted in an aerated bioreactor with a stirring system in four experimental series, each composed of five processes run at temperatures of 27, 36, 45, 54 and 63 °C. In the first and second series, medium pH was not controlled, the initial pH amounted to 6.5 and 8.0, respectively. In the third and fourth series, medium pH was controlled at 6.5 and 8.0, respectively. Under optimal conditions, the pollution load of the vinasse stillage expressed as soluble chemical oxygen demand was removed with an 88.73% efficiency. The bacterial culture assimilated all organic pollutants simultaneously, but the rate of assimilation was different. An exception was the process of betaine assimilation, which intensified only when readily available carbon sources were depleted in the medium. Synthesis and assimilation of organic acids were observed in all experiments. Advantages of the proposed method include: possibility of its use at high temperatures, and no necessity for medium pH adjustment during the process.


2013 ◽  
pp. 67-80
Author(s):  
Branislav Kovacevic ◽  
Dragana Miladinovic ◽  
Marina Katanic ◽  
Zoran Tomovic ◽  
Sasa Pekec

The effect of low initial medium pH on shoot and root development of five white poplar (Populus alba L.) genotypes was tested. The shoot height, fresh mass of shoots per jar, dry mass of shoots per jar, number of roots, as well as the length of the longest root were measured and final pH of the media determined, after 35 days of culture in vitro. Three initial pH values of the medium were tested: 3.0, 4.0 and 5.5 as control. Agar solidification at pH 3.0 was not achieved after sterilization in autoclave, but it was successful after sterilizing in a microwave oven. The obtained results indicate that the tested genotypes are able to significantly influence the changes of media pH during culture. The effect of differences among the examined media was significant for biomass accumulation and final media pH. Generally, significantly higher values of fresh and dry shoot mass, shoot height and the longest root length were recorded on a medium with initial pH 3.0 then on a standard medium with pH 5.5.The implications of the obtained results for the improvement of in vitro propagation of white poplars are discussed.


2016 ◽  
Vol 19 (2) ◽  
pp. 100
Author(s):  
Anhar Rozi ◽  
Sugeng Heri Suseno ◽  
Agoes Mardiono Jacoeb

Silky shark liver was 10-15% of its body mass and 50% of oil is contained in the liver. The aimed of<br />this study was to determine heavy metal content, fatty acid profile on raw material, extraction of its oil, and<br />parameter of oxidation. The method of heavy metal test stated on the SNI and fatty acid analysis referred<br />to AOAC. The extraction was oven methode at 50, 60, 70, and 80°C in 8 hours. Cadmium (Cd) as the<br />highest heavy metal content with 0.88±0.01 ppm, SFA was 18.46% composed by palmitic acid dominantly<br />(12.59%). The MUFA was 24.54 % with the highest oleic acid (17.86%). PUFA was 19.11 % that consist of<br />DHA (14.35%) as the most abundantly present while EPA was 1.50%. Shark liver oil which was extracted<br />at 50°C had the highest yield (24.47%). The oxidation of silky shark liver oil extraction indicated the best<br />treatment at 50°C with peroxide value (PV), p-Anisidine value (p-AV), percentage of free fatty acid (% FFA),<br />acid value (AV), and total oxidation (TOTOX) were 7.26±1.27 mEq/kg, 16.79±0.28 mEq/kg, 5.47±0.12%,<br />10.88±0.25 mg KOH/kg, and 31.31±2.26 mEq/kg respectively.


There are numerous previous studies working on biosynthesis, properties and applications of bacterial cellulose (BC) membrane from Acetobacter xylinum bacteria strain. However, there is less research examining the effect of initial pH level on BC membrane properties. Here, BC membranes were produced at different pH level (concentration of acetic acid) of coconut water-based culture medium which are 3.5, 4.0, 4.5, 5.0 and 5.5 for 7 days, statically. The effect of initial pH level during BC production on morphology, physical and characteristics were investigated. The Acetobacter xylinum membrane were studied its crystallinity using X-ray diffraction, FTIR analysis for chemical structure and FESEM for morphological analysis. In addition, the different of initial pH level does affect the membrane yield and breathability properties using an Upright Cup Method of water vapour permeability testing. Although certain suitable amount of acid had reduced the production yield, a breathable BC membrane was produced.


Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4228
Author(s):  
Tuula Jyske ◽  
Hanna Brännström ◽  
Tytti Sarjala ◽  
Jarkko Hellström ◽  
Eelis Halmemies ◽  
...  

Softwood bark is an important by-product of forest industry. Currently, bark is under-utilized and mainly directed for energy production, although it can be extracted with hot water to obtain compounds for value-added use. In Norway spruce (Picea abies [L.] Karst.) bark, condensed tannins and stilbene glycosides are among the compounds that comprise majority of the antioxidative extractives. For developing feasible production chain for softwood bark extractives, knowledge on raw material quality is critical. This study examined the fate of spruce bark tannins and stilbenes during storage treatment with two seasonal replications (i.e., during winter and summer). In the experiment, mature logs were harvested and stored outside. During six-month-storage periods, samples were periodically collected for chemical analysis from both inner and outer bark layers. Additionally, bark extractives were analyzed for antioxidative activities by FRAP, ORAC, and H2O2 scavenging assays. According to the results, stilbenes rapidly degraded during storage, whereas tannins were more stable: only 5–7% of the original stilbene amount and ca. 30–50% of the original amount of condensed tannins were found after 24-week-storage. Summer conditions led to the faster modification of bark chemistry than winter conditions. Changes in antioxidative activity were less pronounced than those of analyzed chemical compounds, indicating that the derivatives of the compounds contribute to the antioxidative activity. The results of the assays showed that, on average, ca. 27% of the original antioxidative capacity remained 24 weeks after the onset of the storage treatment, while a large variation (2–95% of the original capacity remaining) was found between assays, seasons, and bark layers. Inner bark preserved its activities longer than outer bark, and intact bark attached to timber is expected to maintain its activities longer than a debarked one. Thus, to ensure prolonged quality, no debarking before storage is suggested: outer bark protects the inner bark, and debarking enhances the degradation.


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