Steam Explosion Pretreatment and Ethanol Extraction of Wheat Straw

2011 ◽  
Vol 183-185 ◽  
pp. 635-638
Author(s):  
Lan Feng Hui ◽  
Ting Zhao ◽  
Chuan Ling Si ◽  
Zhong Liu

It has been increasing the interest in the study of alternative pulping processes that conciliate high performance and protection to the environment. In the same way, the use of agricultural residues has been more and more reminded as promising raw material for production of bioethanol and chemical products. The wheat straw is a very abundant agricultural residue and it has been used in many countries for the production of cellulosic pulps. This work describes the effect of the pretreatment by steam explosion on the ethanol-water extraction of wheat straw. The samples of wheat straw were treated by steam explosion at 190°C and 210 °C for 4 minutes and later transferred to the treatment with ethanol-water (1:1, v:v) at different temperatures (140, 160 and 200 °C) and 60 minutes as reaction times. The pretreatment led to an increase in the amount of extracted lignin in the ethanol pulping. This effect was more pronounced in the pulping performed at lower temperatures. The use of higher temperatures in the treatment by steam explosion was more significant as shown by lower pulp yield and higher extractive extent.

2012 ◽  
Vol 200 ◽  
pp. 335-338 ◽  
Author(s):  
Peng Luo ◽  
Chuan Min Yang ◽  
Hong Wei Ji

The goal of this work was to make particleboards for manufacturing pallets from wheat straw using low cost urea formaldehyde (UF) resin adhesive. The wheat straws were subject to steam explosion pretreatment to improve bondability with UF resin. Particleboards were obtained from the steam explosion pretreated wheat straws with UF resin. Particleboard manufacturing parameters, such as pressing time, temperature and board density, were optimized to achieve high performance panel board for pallets. The optimum parameters were found to be: hot press temperature 170 °C, hot press time 40 s/mm, resin application ratio 10%, and straw particle size 12 mm. Under the optimum conditions particleboards met the mechanical requirements for the industrial use particleboards based on the Chinese National Standard for Particleboard and were able to make pallets.


2011 ◽  
Vol 236-238 ◽  
pp. 1431-1436
Author(s):  
Jing Liu ◽  
Katsuya Nagata

Alkaline sulfite/anthraquinone (AS/AQ) pulping of wheat straw under different conditions was conducted in this study. A transition point of kappa number at approximately 6.5 was observed based on all experimental results. This transition point can be regarded as the phase transfer point in AS/AQ pulping from bulk to residual delignification. Effective delignification without great lost of pulp yield can be achieved before kappa number was below this transition point during AS/AQ pulping of wheat straw. It is found that the ratio of cooking liquid to solid should not be lower than 6, if good mass transfer of chemicals and lignin dissolving is needed. As the ratio of Na2SO3 to NaOH dosage ranged from 0.4 to 2.4, low proportion of Na2SO3 allows effective delignification while no serious degradation of carbohydrate. Moreover, similar to kraft pulping, addition of AQ in the range of 0.05% to 0.25% is useful to remove lignin and protect the carbohydrate during AS/AQ pulping. Finally, although the transition point of kappa number may be changed while different raw material used for same pulping process or different pulping process for same raw materials, it is of interest and important for mill practice.


2015 ◽  
Vol 179 ◽  
pp. 299-305 ◽  
Author(s):  
Franz Theuretzbacher ◽  
Javier Lizasoain ◽  
Christopher Lefever ◽  
Molly K. Saylor ◽  
Ramon Enguidanos ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4425
Author(s):  
Renny Febrida ◽  
Arief Cahyanto ◽  
Ellyza Herda ◽  
Vanitha Muthukanan ◽  
Nina Djustiana ◽  
...  

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.


2021 ◽  
Vol 115 ◽  
pp. 29-36
Author(s):  
Florentyna Akus-Szylberg ◽  
Andrzej Antczak ◽  
Janusz Zawadzki

Effects of soaking aqueous ammonia pretreatment on chemical composition and enzymatic hydrolysis of corn stover. The aim of this research was to investigate the effect of applying two different temperatures of the soaking aqueous ammonia treatment on the chemical composition and enzymatic hydrolysis yield of the corn stover. Native corn stover as well as solid fractions after 20 h of alkali pretreatment performed at 15% ammonia solution and at 50 °C or 90 °C were analysed in terms of cellulose, holocellulose, lignin and extractives content. Both untreated and treated samples were subjected to the enzymatic hydrolysis and hydrolysates were examined with a high performance liquid chromatography (HPLC). Results indicated a significant development of enzymatic digestibility of the SAA treated biomass. Furthermore, a 38.7% and a 68.9% delignification levels in the biomass treated with ammonia at respectively 50 °C and 90 °C process comparing to the raw material were achieved.


2012 ◽  
Vol 472-475 ◽  
pp. 2828-2833
Author(s):  
Yan Qiao Jin ◽  
Yi Zhuan Zhang ◽  
Xian Su Cheng

In this study, wheat-straw lignocelluloses were liquefied in liquefaction solvents. Polyethyleneglycol 400 (PEG 400) and ethylene glycol (EG) were used as main liquefaction solvents. The effect of liquefaction time and liquefaction solvents on the properties of liquefied products was investigated. As the reaction time increased, the hydroxyl value, residue content and viscosity decreased, and the acid value decreased gradually in the previous period of time then increased. The optimum liquefaction conditions were as follows: wheat-straw lignocelluloses with steam-explosion pretreatment, the main liquefaction reagent of PEG 400, auxiliary liquefaction solvents of glycerin, catalyst of sulfuric acid, liquefaction temperature of 150°C, liquefaction time of 4 h. The hydroxyl value of liquefaction product was 206 mgKOH/g, the residue content was 0.19% and the viscosity was 88 mPa•s.


2011 ◽  
Vol 179-180 ◽  
pp. 807-811 ◽  
Author(s):  
Peng Luo ◽  
Chuan Min Yang

Wheat straw is one of the most abundant and cheap lignocellulosic waste materials in the world. Nowadays, field burning is the major practice for removing wheat straw due to lack of effective utilization, but it increases the air pollution and consequently affects public health. Wheat straw is an attractive lignocellulosic raw material for binderless particleboard production. In this study, steam explosion was adopted as pretreatment method for wheat straw. The pretreated wheat straw was used to produce binderless particleboard panels. The influence of both pretreatment temperature and residence time on chemical composition of wheat straw, and modulus of rupture, internal bond and water absorption of panel boards was investigated. The results showed that defiberation of wheat straw raw material occurred during steam explosion pretreatment. The modulus of rupture and internal bond increased while water absorption of panels decreased as pretreatment severity increased. The optimum pretreatment condition, with 19.8 MPa of modulus of rupture, 0.2572 MPa internal bond and 61.5% of water absorption of panels, occurred under 170°C temperature and 10 minute residence time.


2020 ◽  
Vol 19 (1) ◽  
pp. 80-97
Author(s):  
Andrej Pažitný ◽  
Albert Russ ◽  
Štefan Boháček ◽  
Štefan Šutý ◽  
Vladimír Ihnát

Monosaccharides such as glucose, xylose and arabinose are the main monomer units of which cellulose and hemicelluloses are composed. The cellulose and hemicelluloses content in many biomass species makes them suitable for 2G bioethanol production. Today, when 1G bioethanol production is closely monitored due to its enormous consumption of food raw materials such as wheat or corn grains, larger companies are gradually moving to pilot operations of 2G bioethanol production. However, cellulose and hemicelluloses contained in biomass are only very slightly accessible to enzymes used in 2G bioethanol production. Therefore pretreatment methods such as steam explosion are very suitable to use for fractionation of cell structure. In this paper, we tested the cellulose accessibility. We compared the cellulose accessibility of wheat straw particles with wooden particles obtained from beech and poplar. Particle size was less than 0.7 mm. We identified the optimal conditions of steam explosion pretreatment at reaction temperature of 200 °C for wheat straw, poplar and beech wood particles. The main indicator of accessibility was concentration of monomers obtained from enzymatic hydrolysis. The concentration of monomer was determined by high performance liquid chromatography. The experimental results showed different accessibility measure for each type of biomass species.


2019 ◽  
Vol 9 (24) ◽  
pp. 5525 ◽  
Author(s):  
Eri J. Paz-García ◽  
Silvia P. Paredes-Carrera ◽  
Sergio O. Flores-Valle ◽  
Isis S. Rodríguez-Clavel ◽  
Jesús C. Sánchez-Ochoa ◽  
...  

In this study, CuO was synthesized as a microwave absorber in the pyrolysis of a biomass model (sugarcane bagasse). CuO was synthesized for 5 min of irradiation using the following techniques: microwave (MW), ultrasound (US), combined mode (MW-US), and conduction heating (CH) as a reference material. The use of these treatments promotes changes in the morphology, as MW and US generate leaves and monolithic faceted morphologies, respectively. Changes were also generated in some textural characteristics such as crystal size, surface area, and volume-pore size. They were produced as a consequence of changes in the conditions during the crystallization stage produced by the different irradiation types. The microwave-assisted pyrolysis was performed aiming for the maximum liquid fraction (bio-oil) in the products. The reaction time, the size of the biomass, and the CuO synthesis method were also analyzed. The following particle size (ps) intervals were studied: ps < 0.5 mm, 0.5 mm < ps < 1.7 mm, 1.7 mm < ps < 3.5 mm. The best conditions at 1160 Watts in the microwave were: 4 min of reaction, particle size lower than 0.5 mm, and CuO synthesized by US. The use of CuO in the pyrolysis almost triples the amount of the obtained liquid fraction, when compared with the pyrolysis without the use of a microwave absorbent. The CuO was reduced to Cu2O and Cu after the pyrolysis. In this work, a reduction in the reaction times from hours to minutes was achieved during the synthesis of CuO and the pyrolysis biomass. The liquid fraction (bio-oil) can be raw material to obtain value-added chemical products or biofuels.


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