Biodegradation
pardis yousefi; Sepideh Hamedi; Esmaeil Rasooly Garmaroody; mojtaba koosha
Abstract
Bio-refinery includes technologies which can convert biomass resources to valuable products. In this study, carboxymethylation of the xylan-rich hemicelluloses extracted from sugarcane bagasse pith was performed. DS of the carboxymethyl xylan (CMX) was determined 0.68 using ICP-OES analysis. The presence ...
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Bio-refinery includes technologies which can convert biomass resources to valuable products. In this study, carboxymethylation of the xylan-rich hemicelluloses extracted from sugarcane bagasse pith was performed. DS of the carboxymethyl xylan (CMX) was determined 0.68 using ICP-OES analysis. The presence of absorption bands at 1580 and 1311 cm-1 in the FTIR spectrum of the modified xylan are associated to the stretching vibration of C-O bonds of carboxymethyl groups. The carboxymethyl xylan/chitosan (CMX/CS) films were then prepared by casting method. XRD pattern showed that the intensity of the characteristic peaks of the chitosan reduced after film preparation which may be due to decreasing the crystalline nature of the film. SEM images showed that the surface of the film is uniform. The observed exothermic peak in DSC thermograms showed that the films degraded at higher than 200oC. Water vapor permeability (WVP) of the carboxymethyl xylan/chitosan film was measured 0.84± 0.1 g mm/m2 h kPa. Colorimetric analysis proved that the white index (WI) of the CMX/CS film increased as compared with xylan/chitosan film. In contrary, the yellow index (YI) of the CMX/CS film decreased. Swelling ratios of the CMX/CS and xylan/CS films were measured as 130.42 and 95.71 respectively. The prepared CMX/CS films exhibited higher tensile strength in compared to xylan/chitosan film. This may be resulted from the interactions between amine groups of chitosan and carboxyl groups of CMX. CMX/CS film exhibited the higher antibacterial activity against E. coli that S. aureus.
Chemical conversion
Niloufar Davodi; Esmaeil Rasooly Garmaroody; Omid Ramezani; Sepideh Haamedi
Abstract
In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent ...
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In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent compounds from the above pretreatment hydrolyzates was performed. In the overliming, calcium hydroxide and sulfuric acid, in activated carbon method, activated carbon was used at three levels (0.5, 1.5 and 2.5%) and in the combined method of the combination of materials in the two previous methods became after acid treatments and each of the methods of insemination, the amount of recovered sugars and the values of the inhibitory compounds of furfural and hydroxymethylfurfural in the hydrolyzate were measured as two important indicators. The results showed that application of the above methods on hydrolyzate increased the yield of reduced sugars, so that the highest sugar yield (˃32%) was obtained after the independent method of overliming. In addition, active and combined carbon autonomous methods (overlimming and activated carbon) have an optimum activated carbon consumption of 2.5 and 1.5%, respectively. The qualitative study of the presence of inhibitory agents in hydrolyzates showed that furfural and hydroxymethylfurfural have maximum absorption at wavelengths of 276 and 282 nm. Also, an overliming with 2.5% activated carbon as the best method could eliminate up to 100% of inhibitory compounds. On the other hand, the autonomous method of overliming, with the removal of ˃90% of the inhibitory compounds, also has the highest sugar yield. Therefore, taking into account simultaneously the rate of sugar yield and the elimination of deterrent compounds, two independent alternatives of Overliming and Overliming with 2.5% active carbon could be proposed for the production of bioassays, such as bioethanol, xylitol, ... from the pith of bagasse.
Chemical conversion
Fatemeh Jadidyan; Mohammad Talaeipoor; Saeed Mahdavi; Amirhoman Hamasi
Abstract
The purpose of this study is the evaluation of bagasse pith for heating energy and activated carbon production. To assess the energy production of the pith, bulk density, melting point, and heating value were measured. Furthermore, percentage of moisture, ash, volatile compounds, fixed carbon, lignin, ...
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The purpose of this study is the evaluation of bagasse pith for heating energy and activated carbon production. To assess the energy production of the pith, bulk density, melting point, and heating value were measured. Furthermore, percentage of moisture, ash, volatile compounds, fixed carbon, lignin, and elements contents were determined. Ash and volatile content average were measured at 30.23% and 67.14%, respectively. The bulk density average of the pith powder with 80 meshes was determined at 0.15 g/cm3. Lignin content and melting point of pith is measured 23.1%, and 1050 °C, respectively. Sulfur content is important in terms of environmental pollution and it was determined 0.3%. Gross heating value was measured directly by calorimeter bomb to 10.30 MJ/kg that is lower than bagasse and wood. The activated carbon produced from pyrolysis of bagasse pith was chemically activated with zinc chloride. The chemically activated carbons were characterized by measuring iodine of 504 mg/g, specific surface (BET) of 478 m2/g, and pore diameter of 7.45 nanometer. It is suitable for liquid absorption according to the pore size.
