scholarly journals Extraction and Characterization of Microfibrillated Cellulose from Discarded Cotton Fibers through Catalyst Preloaded Fenton Oxidation

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xianmeng Xu ◽  
Ning Lu ◽  
Shunmin Wang ◽  
Mengqi Huang ◽  
Shenglong Qu ◽  
...  
Keyword(s):  
High Pressure ◽  
High Speed ◽  
Crystallinity Index ◽  
Microfibrillated Cellulose ◽  
Fenton Oxidation ◽  
Cotton Cellulose ◽  
Practical Significance ◽  
Sodium Chlorite ◽  
Mixed Solution ◽  
High Pressure Homogenization

With rapid developments in science and technology, mankind is faced with the dual severe challenges of obtaining needed resources and protecting the environment. The need for sustainable development strategies has become a global consensus. As the most abundant biological resource on Earth, cellulose is an inexhaustible, natural, and renewable polymer. Microfibrillated cellulose (MFC) offers the advantages of abundant raw materials, high strength, and good degradability. Simultaneously, MFC prepared from natural materials has high practical significance due to its potential application in nanocomposites. In this study, we reported the preparation of MFCs from discarded cotton with short fibers by a combination of Fe2+ catalyst-preloading Fenton oxidation and a high-pressure homogenization cycle method. Lignin was removed from the discarded cotton with an acetic acid and sodium chlorite mixed solution. Then, the cotton was treated with NaOH solution to obtain cotton cellulose and oxidized using Fenton oxidation to obtain Fenton-oxidized cotton cellulose. The carboxylic acid content of the oxidized cotton cellulose was 126.87 μmol/g, and the zeta potential was −43.42 mV. Then, the Fenton-oxidized cotton cellulose was treated in a high-speed blender under a high-pressure homogenization cycle to obtain the MFC with a yield of 91.58%. Fourier transform infrared spectroscopy (FTIR) indicated that cotton cellulose was effectively oxidized by Fe2+ catalyst-preloading Fenton oxidation. The diameter of the MFC ranged from several nanometers to a few micrometers as determined by scanning electron microscopy (SEM), the crystallinity index (CrI) of the MFC was 83.52% according to X-ray diffraction (XRD), and the thermal stability of the MFC was slightly reduced compared to cotton cellulose, as seen through thermogravimetric analysis (TGA). The use of catalyst-preloading Fenton oxidation technology, based on the principles of microreactors, along with high-pressure homogenization, was a promising technique to prepare MFCs from discarded cotton.

scholarly journals Cavitation patterns in high-pressure homogenization nozzles with cylindrical orifices: Influence of mixing stream in Simultaneous Homogenization and Mixing

2021 ◽  
Author(s):  
V. Gall ◽  
E. Rütten ◽  
H. P. Karbstein
Keyword(s):  
High Pressure ◽  
Process Design ◽  
High Speed ◽  
State Of The Art ◽  
Back Pressure ◽  
High Pressure Homogenization ◽  
Unit Operation ◽  
Mixing Chamber ◽  
Cavitation Intensity ◽  
Droplet Sizes

AbstractHigh-pressure homogenization is the state of the art to produce high-quality emulsions with droplet sizes in the submicron range. In simultaneous homogenization and mixing (SHM), an additional mixing stream is inserted into a modified homogenization nozzle in order to create synergies between the unit operation homogenization and mixing. In this work, the influence of the mixing stream on cavitation patterns after a cylindrical orifice is investigated. Shadow-graphic images of the cavitation patterns were taken using a high-speed camera and an optically accessible mixing chamber. Results show that adding the mixing stream can contribute to coalescence of cavitation bubbles. Choked cavitation was observed at higher cavitation numbers σ with increasing mixing stream. The influence of the mixing stream became more significant at a higher orifice to outlet ratio, where a hydraulic flip was also observed at higher σ. The decrease of cavitation intensity with increasing back-pressure was found to be identical with conventional high-pressure homogenization. In the future, the results can be taken into account in the SHM process design to improve the efficiency of droplet break-up by preventing cavitation or at least hydraulic flip.

scholarly journals Enzymatic Coupled Mechanical Defibrillation Process for the Production of Corn (Zea Mays) Cob Microfibrillated Cellulose: Preparation, Characterization and Evaluation as Pickering Emulsifier for Oil-In-Water Emulsion

2021 ◽  
Author(s):  
Teck-Kim Tang ◽  
Yee-Ying Lee ◽  
Eng-Tong Phuah ◽  
Chin-Ping Tan ◽  
Sivaruby Kanagaratnam ◽  
...  
Keyword(s):  
High Pressure ◽  
Shear Viscosity ◽  
Microfibrillated Cellulose ◽  
High Pressure Homogenization ◽  
Corn Cob ◽  
Water Emulsion ◽  
Homogenization Process ◽  
Oil In Water ◽  
High Pressure Homogenizer ◽  
Oil In Water Emulsion

Abstract Microfibrillated cellulose (MFC) is a type of nanocellulose having multiple functionalities. Typically, MFC was produced from mechanical high pressure homogenization process. However, this process is energy intensive and the fibrous nature of MFC often causes instrument blockage. The present study aims to utilize endoglucanse enzyme as environmentally friendly approach to pretreat fiber structure prior to undergoing mechanical defibrillation for the production of MFC from corn cob. Alkaline and bleached pretreated corn cob was treated with endoglucanase Fibercare R from 0% to 2.5% before passing through high pressure homogenizer. It was found that incorporation of 0.02% of endoglucanase was sufficient to soften the corn cob cellulose and further prevent the blockage of homogenizer. Subsequently, the 0.02% endoglucanse treated corn cob was passed through different cycles of homogenization from 0 cycle to 10 cycle for MFC production. It was observed that the water retention, zeta potential and shear viscosity of the MFC increases with homogenization cycle. MFC produced had a gel like consistency. Next, emulsifying stabilizing properties of MFC produced from cycle 0 to cycle 10 as well as their amount from 0 % to 1% were also assessed. Increase in homogenization cycle and the amount of MFC promote emulsion stability as observed from the low creaming index which is mainly attributed to the high shear viscosity and G’G’’ crossover of the emulsion. In all, the MFC derived from corn cob via enzymatic coupled with high pressure homogenization process has the potential to be used as gel like stabilizer in oil-in-water food emulsion system.

Effects of high-speed homogenization and high-pressure homogenization on structure of tomato residue fibers

2017 ◽  
Vol 232 ◽  
pp. 443-449 ◽  
Author(s):  
Xiao Hua ◽  
Shanan Xu ◽  
Mingming Wang ◽  
Ying Chen ◽  
Hui Yang ◽  
...  
Keyword(s):  
High Pressure ◽  
High Speed ◽  
High Pressure Homogenization

scholarly journals Homogeneous Isolation of Nanocellulose from Cotton Cellulose by High Pressure Homogenization

2013 ◽  
Vol 01 (05) ◽  
pp. 49-52 ◽  
Author(s):  
Yihong Wang ◽  
Xiaoyi Wei ◽  
Jihua Li ◽  
Qinghuang Wang ◽  
Fei Wang ◽  
...  
Keyword(s):  
High Pressure ◽  
Cotton Cellulose ◽  
High Pressure Homogenization

Triticale crop residue: a cheap material for high performance nanofibrillated cellulose

RSC Advances ◽  
2015 ◽  
Vol 5 (5) ◽  
pp. 3141-3151 ◽  
Author(s):  
Sami Boufi ◽  
Alessandro Gandini
Keyword(s):  
High Pressure ◽  
Energy Demand ◽  
High Speed ◽  
High Performance ◽  
Crop Residue ◽  
Nanofibrillated Cellulose ◽  
High Pressure Homogenization ◽  
Disintegration Process

Nanofibrillated cellulose from triticale straws were produced using high-pressure homogenization and conventional high-speed blender for the disintegration process. The energy demand for the disintegration process was shown to depend on delignification and pretreatment.

scholarly journals Comparison of oil-in-water emulsions prepared by ultrasound, high-pressure homogenization and high-speed homogenization

2022 ◽  
Vol 82 ◽  
pp. 105885
Author(s):  
Lei Zhou ◽  
Wangang Zhang ◽  
Jingyu Wang ◽  
Ruyu Zhang ◽  
Jian Zhang
Keyword(s):  
High Pressure ◽  
High Speed ◽  
High Pressure Homogenization ◽  
Oil In Water

Cyclone Bomb hits Southern Brazil in 2020

2020 ◽  
Vol 3 (3) ◽  
Author(s):  
Ricardo Gobato ◽  
Alireza Heidari
Keyword(s):  
High Pressure ◽  
Atmospheric Pressure ◽  
High Speed ◽  
Satellite Images ◽  
The State ◽  
Southern Brazil ◽  
Santa Catarina ◽  
High Area ◽  
South Of Brazil ◽  
Rapid Drop

An “explosive extratropical cyclone” is an atmospheric phenomenon that occurs when there is a very rapid drop in central atmospheric pressure. This phenomenon, with its characteristic of rapidly lowering the pressure in its interior, generates very intense winds and for this reason it is called explosive cyclone, bomb cyclone. With gusts recorded of 116 km/h, atmospheric phenomenon – “cyclone bomb” (CB) hit southern Brazil on June 30, the beginning of winter 2020, causing destruction in its influence over. One of the cities most affected was Chapecó, west of the state of Santa Catarina. The satellite images show that the CB generated a low pressure (976 mbar) inside it, generating two atmospheric currents that moved at high speed. In a northwest-southeast direction, Bolivia and Paraguay, crossing the states of Parana and Santa Catarina, and this draft that hit the south of Brazil, which caused the destruction of the affected states.  Another moving to Argentina, southwest-northeast direction, due to high area of high pressure (1022 mbar). Both enhanced the phenomenon.

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