Wheat Straw Powder Research Articles

Bio-oil upgrading by reactive distillation using p-toluene sulfonic acid catalyst loaded on biomass activated carbon

The aim of this work was to investigate the feasibility of a proposed simple bio-oil upgrading technique and test its suitability for bio-oil products. The upgrading technique consisted of vacuum distillation for preliminary water removal, deep water removal, using etylchloride, and catalytic esterification and neutralisation. Two bio-oil samples were produced from slow pyrolysis of sawdust pellets and fast pyrolysis of wheat straw powder. Some activated carbon obtained from slow pyrolysis was the catalyst carrier and p-toluene sulfonic acid was the catalyst. The conditions of the esterification reaction were identified by serious experiments. As a result, the qualities of both bio-oil samples are significantly improved through the upgrade. The heat value of both oils ranged from 14–17 MJ kg−1 to 25–29 MJ kg−1. The final neutralisation step using triethylamine increased the oil pH value close to neutral. The chemical/physical properties of the produced bio-oils were in accordance with the standards for engine fuel.

A New and Environmentally Friendly Route for Preparation of Carbon Microspheres from Wheat Straw

The reactions were performed to synthesize carbon materials using wheat straw powder as raw material. The wheat straw powder was first hydrolyzed at the absence of a catalyst at 190°C for 1 h, then the hydrolyzate solution was used as carbon source to prepare carbon materials via hydrothermal carbonization at 180°C in the absence of a catalyst for 8 h. The influence of solid-liquid-ratio of wheat straw to water on the morphology of the product was investigated. The samples were examined by a scanning electron microscope and Fourier transform infrared spectroscopy. The results show that the product was carbon microspheres with a large number of O–H, CHO, and other functional groups, and the diameters of carbon microspheres noticeably depended on the solid-liquid ratio. When the solid-liquid ratio was 1 : 60, the diameters of carbon microspheres were in the range of 100 to 300 nm when the solid-liquid ratio was 1 : 40, carbon microspheres with larger and more uniform diameters mostly about 250 nm were obtained, and when the solid-liquid-ratio was 1 : 20, there were more larger carbon microspheres with diameters about 800 nm in the product and the surface of these carbon microspheres is smoother, whereas; the uniformity of the product deteriorates.

Production of lactic acid from xylose and wheat straw by Rhizopus oryzae

Rhizopus oryzae NBRC 5378 was the best among 56 strains of R. oryzae for the production of lactic acid from xylose. This strain produced lactic acid from wheat straw powder by a simultaneous saccharification and fermentation process, with a yield of 0.23 g/g from cellulose and hemicellulose in wheat straw.

Measurements of Final Volatiles Yield of Biomass Devolatization at Flash Heating Rate

Final volatiles yield of biomass devolatization at flash heating rate was determined via experiments. Samples of wheat straw and corn stalk powder were dispersed in the feeder and were carried by argon into the laminar entrained flow reactor. Flash devolatization of tiny biomass particles was accomplished in the moderate temperature reactor. Residue was collected and the ash content of it was detected in a thermo-grametric analyzer. Final volatiles yield was calculated using ash trace method. Altogether, 96 experiments (including repeat ones) of different reaction temperature (500, 550, 600, 650 °C), different collecting distance (550, 600, 650, 700 mm away from inlet). Results showed that final volatiles yields of wheat straw and corn stalk are 79%, 85 % separately. High reproducibility of the experiments showed it is a reliable method to determine final volatiles yield of biomass devolatization at flash heating rate. Kinetic parameters for wheat straw and corn stalk were modified as A=1009/s, E=3782kJ/mol and A=596/s, E=3716kJ/mol, respectively.

Analysis on Products and Residues of Liquefaction of Wheat Straw & Polyester in Supercritical Ethanol

The mixture of wheat straw (WS) and polyester (PC) was liquefied in supercritical ethanol. Liquefied products produced and liquefied residue from the liquefaction under different supercritical conditions were analyzed by GC-MS, SEM and IR. GC-MS analysis of the liquefied products indicates that ethanol would decompose. And the most compounds in the liquefied product had the structure of phenol and phenol derivatives, which came from the degradation products of PC and WS. SEM analysis show that the wheat straw powder possessed larger particles with smooth surfaces while the residue from liquefaction had smaller particles with rough surfaces because of drastically degraded from the wheat straw powder surface under supercritical conditions. FT-IR analysis showed that the lignin was easily degraded during the liquefaction process, and also found to the cellulose is very difficult to liquefy for its crystalline structure.

Response of transgenic potato seedlings to allelopathic pressure and the effect of nutrients in the culture medium

Chinese farmers frequently use a wheat–potato cropping system. The land area planted to transgenic potatoes is increasing because transgenic potatoes have greater resistance to pests and diseases. However, little is known about the bio-compatibility of transgenic potatoes with wheat straw. The objective of this tissue culture study was to determine the allelopathic effects of wheat straw on transgenic potato seedlings. Seedlings were cultured on normal MS medium (normal treatment) and nutrient-deficient MS medium (acclimated treatment) and then transferred to MS medium, which contained wheat straw powder. Wheat straw powder inhibited potato seedling growth in both treatments. Among the parameters analyzed in this study, inhibition was greatest for plant fresh weight and least for plant height. The inhibitive effects of wheat straw were greater for seedling roots compared to shoots. Resistance to allelopathic pressure from wheat straw was greater in acclimated seedlings compared to normal seedlings. This suggested that previous pressure may have induced tolerance in the transgenic potato seedlings. Furthermore, growth inhibition of potato seedlings from the normal treatment increased as the amount of wheat straw powder in the culture medium increased. Calculations indicated that the presence of wheat straw would lead to a 55% reduction in the total biomass of normal potato seedlings compared to a 39% reduction for acclimated seedlings. Parameters such as net photosynthesis rate (Pn) and quantum yield (Y(II)) changed as the nutrient content of the culture medium increased or decreased, but the changes in the parameters were smaller for acclimated seedlings compared to normal seedlings. This suggests that nutrient status during the culture period could help transgenic potato seedlings adapt and compensate for energy loss from seedlings in defending against allelopathic pressure. In summary, the results show that previous exposure to pressures such as nutrient deficiency may increase the allelopathic pressure resistance of transgenic potato seedlings.

Synthesis of wheat straw-g-poly(acrylic acid) superabsorbent composites and release of urea from it

Wheat straw (WS) was used as raw material for synthesizing a novel wheat straw-g-poly(acrylic acid) (WS/PAA) superabsorbent composite by graft polymerization with wheat straw powder and acrylic acid in aqueous solution. The effect of wheat straw on water absorbency was discussed and the highest water absorbency was obtained when the amount of wheat straw in the feed was 20%. The superabsorbent composite was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results of FTIR spectra showed OH of WS participated in graft polymerization with acrylic acid. The influences of pH, cations and anions on equilibrium water absorbency of WS/PAA were investigated. The superabsorbent composite was swollen in aqueous solution of urea to load urea, and the results showed urea concentration had no obvious effect on the swelling behaviors of WS/PAA. Furthermore, the release of urea from loaded WS/PAA was analyzed in water and in soil. Urea diffusion coefficient D was calculated.

Measurement of the heat of smoldering combustion in straws and stalks by means of simultaneous thermal analysis

Abstract In order to investigate reaction heat of agro-stalks smoldering, wheat straw, corn stalk, cotton stalk, millet straw, sorghum stalk and sweet potato rattan powder were smoldered and pyrolyzed in a simultaneous thermal analyzer (STA). The samples were placed in a platinum crucible (∅5 mm×5 mm) with a lid (with a ∅1 mm hole) on a high-accuracy differential scanning calorimetry–heat capacity (DSC-cp) holder in the furnace of an STA and heated from 303 to 1073 K at a heating rate of 10 K min−1. Sweeping gas with a flow rate of 25 ml min−1 was air and nitrogen during smoldering and pyrolysis, respectively. Results showed that the heat emission characteristic of the smoldering process differed remarkably from the pyrolysis process. Based on the analysis of the DSC curves, oxidative polymer degradation heat and char oxidation heat were obtained from experimental data. It showed that the oxidative polymer degradation heat of the agro-stalks is more than 6.92 MJ kg−1 consumed matter, higher than that of cellulose paper. And char oxidation heat is around 23 MJ kg−1 consumed matter, similar to that of cellulose paper, but higher than that of cigarette. Total net heat emission of smoldering in STA was also obtained. These data can be used as reference data in analyzing smoldering of agro-stalks under similar conditions.

Identification, Ligninolytic Enzyme Activity and Decolorization Potential of Two Fungi Isolated from a Distillery Effluent Contaminated Site

Two fungal strains producing ligninolytic enzymes and having the potential to decolorize distillery effluent were isolated from the soil of a distillery effluent contaminated site. DNA was isolated from the pure cultures of these fungi and polymerase chain reaction (PCR) amplification of their internal transcribed spacer (ITS) region of nuclear ribosomal DNA was carried out. Further, the DNA was sequenced and the comparison of generated sequence with database led to their identification as Penicillium pinophilum TERI DB1 and Alternaria gaisen TERI DB6 respectively. These two isolates along with one isolate of Pleurotus florida EM 1303 were assessed for their ligninolytic enzyme activity in culture filtrate as well as after solid state fermentation on two substrates wheat straw and corncob powder. Ergosterol was measured to assess the growth of fungi on solid media. Both P. pinophilum TERI DB1 and A. gaisen TERI DB6 were found to produce laccase, manganese-dependent peroxidases (MnP) and lignin peroxidases (LiP). The immobilized fungal biomass was then used for decolorization of the post biomethanated wastewater from the distillery. Reduction in color up to the magnitude of 86, 50 and 47% was observed with P. florida, P. pinophilum and A. gaisen respectively.

Production of Xylanase of Bacillus coagulans and its bleaching potential

The production of xylanase from Bacillus coagulans has been studied with respect to the environmental parameters, the carbon source and the concentration of carbon source at the shake flask level. Among the various carbon sources used, wheat straw powder favoured higher enzyme production. Xylan isolated from wheat straw gave higher enzyme production as compared to the birchwood xylan. Maximum enzyme activity of 165 IU/ml was obtained with 2% wheat straw xylan in a shake flask study. Improvement of xylanase production was achieved by increasing the wheat straw powder concentration up to 3%. Enzyme has optimum activity at a temperature of 55 °C and pH of 7. The concentrated crude enzyme was found to reduce the kappa number of enzyme-treated eucalyptus pulp by␣5.45% with a marginal increase in the CED viscosity of the enzyme treated pulp as compared to the non-enzymatically treated pulp.

Control of Pythium damping-off of sugar beet by seed treatment with crop straw powders and a biocontrol agent

Abstract Seed treatment with non-sterilized powdered straws from 39 crops was tested for the control of Pythium damping-off of sugar beet. Four straws, including flax, coriander, pea, and lentil were effective in controlling the disease in soil artificially infested with Pythium sp. “group G.” Sterilizing flax and pea straws eliminated the efficacy of these straws. Wheat straw powder coated on sugar beet seeds increased the incidence of Pythium damping-off but this effect was reversed by the co-inoculation of wheat straws with the biocontrol agent Pseudomonas fluorescens 708. Coating sugar beet seeds with P. fluorescens 708 and flax or pea straws also increased the efficiency of the bacterial strain for the control of Pythium damping-off. Pea straws and to a lesser extent lentil straws produced volatile substances that affected mycelial growth of Pythium sp. “group G” on potato dextrose agar in Petri plates when the straws were mixed with water and left to ferment for two days. Fermentation of pea straws led to the accumulation of volatile ammonia, which was produced by the reduction of the large amount of nitrate stored in the straw. Reduction of nitrate and therefore the release of volatile ammonia did not occur in sterilized pea straws. However, fermenting sterile pea straws with bacteria from different genera restored nitrate reduction and the release of volatile ammonia, suggesting that microorganisms associated with pea straws are responsible for the conversion of nitrate into volatile ammonia which in turn control Pythium damping-off disease in sugar beet.

Methane emission from a simulated rice field ecosystem as influenced by hydroquinone and dicyandiamide

A simple apparatus for collecting methane emission from a simulated rice field ecosystem was formed. With no wheat straw powder amended all treatments with inhibitor(s) had so much lower methane emission during rice growth than the treatment with urea alone (control), which was contrary to methane emission from the cut rice–soil system. Especially for treatments with dicyandiamide (DCD) and with DCD plus hydroquinone (HQ), the total amount of methane emission from the soil system and intact rice–soil system was 68.25–46.64% and 46.89–41.78% of the control, respectively. Hence, DCD, especially in combination with HQ, not only increased methane oxidation in the floodwater–soil interface following application of urea, but also significantly enhanced methane oxidation in rice root rhizosphere, particularly from its tillering to booting stage. Wheat straw powder incorporated into flooded surface layer soil significantly weakened the above-mentioned simulating effects. Regression analysis indicated that methane emission from the rice field ecosystem was related to the turnover of ammonium-N in flooded surface layer soil. Diminishing methane emissions from the rice field ecosystem was significantly beneficial to the growth of rice.

Formation of enzymes by biodegradation of agricultural wastes with white rot fungi

Three different strains of white rot fungi, Phanerochaete chrysosporium NRRL 6359, P. chrysosporium NRRL 6361 and Coriolus versicolor NRRL 6102, were tested for their ability to produce xylananse, glucanase and cellulase, and also for their ability to produce release-reducing sugars and proteins in basal media. P. chrysosporium NRRL 6359 was the most active strain for enzyme production. This organism was tested for its ability to produce different enzymes and release-reducing sugars with agricultural wastes as substrates (xylan, treated sugar cane bagasse, sugar cane bagasse, wheat straw, corn cobs, rice husks, peanut shells and cellulose powder). Corn cobs, treated sugar cane bagasse and wheat straw were the most suitable substrates for all products. The optimum pH for cellulase production was found to be 5.5 with wheat straw and 6.5 with treated sugar cane bagasse. For glucanase production the optimum pH ranged between 6.5 and 7.5, whilst for xylanase production the optimum pH ranged between 4.5 and 5.5 for all substrates over an incubation period of 7 days. Further studies revealed that the organisms could produce enzymic activity in agricultural wastes at concentrations of 0.25–3.5% (w/v). 0.2% glucose, yeast or peptone were added to the studied agricultural waste media to detect their repression and induction character.

Cellulase Activities of Some Aerobic Micro-organisms Isolated from Soil

Cellulose extracted from wheat straw, Avicel and CF11 cellulose powder contained 90% (w/w) glucose, whereas filter paper and carboxymethylcellulose contained 18% and 28% (w/w) hemicelluloses, respectively. The straw cellulose was used as the sole carbon source to enrich for a mixed culture of micro-organisms in a stirred liquid medium and on a perfusion column containing glass beads. Amongst the micro-organisms isolated only fungi had cellulase activity and this activity was greatest in cultures of Cladosporium cladosporoides. The remainder of the community consisted of non-cellulolytic secondary organisms. The interactions of cellulolytic fungi with other micro-organisms found in the enrichment mixed culture are discussed.