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Cellulose Fibre from Schinus molle and Its Characterization

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Journal of Renewable Materials 2022年第10期10卷 2593-2606页

作者： Abir Razzak Faten Mannai Ramzi Khiari Younes Moussaoui Mohamed N.Belgacem Laboratory for the Application of Materials to the Environment Waterand Energy(LR21ES15)Faculty of Sciences of GafsaUniversity of GafsaGafsa2112Tunisia Faculty of Sciences of Gafsa University of GafsaGafsa2112Tunisia Laboratory of Environmental Chemistry and Cleaner Process(LR21ES04) University of MonastirMonastir5019Tunisia Higher Institute of Technological Studies(ISET)of Ksar-Hellal Ksar-Hellal5070Tunisia University of Grenoble Alpes CNRSGrenoble INPLGP2GrenobleF-38000France Organic Chemistry Laboratory(LR17ES08) Faculty of Sciences of SfaxUniversity of SfaxSfax3029Tunisia

The exploitation of biomass represents a major environmental challenge related to the protection of the environment and the progressive exhaust of fossil *** this perspective,the main objective of this work is the extraction and the characterization of natural lignocellulosic fibers from the Schinus *** cellulose fibre extraction was investigated employing conditions of alkali *** the alkaline steps,a bleaching treatment was done and let to a yield about 45%pure *** identification of the chemical composition of Schinus molle reveals that this raw material contains a high level of biopolymers with a cellulose rate of 53.2%.Extracted cellulose fibers have been characterized by several techniques such as scanning electron microscopy,Fourier transform infrared,X-ray diffraction,Morfi,and by the determination of their degree of ***-IR results confirm the purity of the cellulosic fibers,and XRD analysis reveals that the crystallinity increases after the delignification and bleaching treatments.

关键词： Schinus molle cellulose alkaline treatment morphological studies

Production and Characterization of High Density Polyethylene Reinforced by Eucalyptus Capsule Fibers

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Journal of Bionic Engineering 2018年第3期15卷 558-566页

作者： Wafa Ouarhim Mohammed-Ouadi Bensalah Denis Rodrigue Hamid Essabir Rachid Bouhfid Abou el kacem Qaiss Moroccan Foundation for Advanced Science Innovation and Research (MAScIR) Institute of Nanomaterials and Nanotechnology (NANOTECH) Laboratory of Polymer Processing Rabat Morocco Faculty of Science Laboratory of Mechanic and Materials (LMM) Mohammed V-Rabat University Rabat Morocco Department of Chemical Engineering and CERMA Universite Laval Quebec G1V0A6 Canada

In this work, Eucalyptus Capsule Fibers （ECF） are proposed as a new natural fiber reinforcement to produce bio-composites due to their biological origin, specific smell and color. High Density Polyethylene （HDPE） is used as the matrix to compare three reinforcement types, raw ECF, alkali treated ECF, and ECF treated with PE-graft-maleic anhydride （PE-g-MA） as a coupling agent at three concentrations （5 wt.%, 10 wt%, and 15 wt%）. A complete set of characterization is performed including tension, torsion, hardness, Melt Flow Index （MFI）, Attenuated Total Reflection Fourier Transform Infrared Spectroscopy （ATR-FTIR）, Contact Angle （CA）, Scanning Electron Microscopy （SEM）, Thermogravimetric Analysis （TGA） and Dynamic Mechanical Analysis （DMA）. The results show that the best mechanical and rheological improvements are obtained by using the coupling agent with alkali treated fibers.

关键词： eucalyptus capsule fibers polyethylene alkaline treatment coupling agent mechanical properties

Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion

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Journal of Environmental Sciences 2009年第3期21卷 279-284页

作者： MAHAR Rasool Bux Department of Environmental Science and Engineering Tsinghua University

alkaline and ultrasonic sludge disintegration can be used as the pretreatment of waste activated sludge （WAS） to promote the subsequent anaerobic or aerobic digestion. In this study, different combinations of these two methods were investigated. The evaluation was based on the quantity of soluble chemical oxygen demand （SCOD） in the pretreated sludge as well as the degradation of organic matter in the subsequent aerobic digestion. For WAS samples with combined pretreatment, the released COD levels were higher than those with ultrasonic or alkaline pretreatment alone. When combined with the ultrasonic treatment, NaOH treatment was more efficient than Ca（OH）2 for WAS solubilization. The COD levels released in various sequential options of combined NaOH and ultrasonic treatments were in the the following descending order： simultaneous treatment 〉 NaOH treatment followed by ultrasonic treatment 〉 ultrasonic treatment followed by NaOH treatment. For simultaneous treatment, low NaOH dosage （100 g/kg dry solid）, short duration （30 min） of NaOH treatment, and low ultrasonic specific energy （7500 kJ/kg dry solid） were suitable for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with optimal parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than that with ultrasonic （42.5%） or with NaOH pretreatment （43.5%） in the subsequent aerobic digestion at the same retention time.

关键词： waste activated sludge (WAS) ultrasonic treatment alkaline treatment aerobic digestion

A FACILE APPROACH FOR THE SURFACE MODIFICATION OF POLY(VINYLIDENE FLUORIDE) MEMBRANE VIA SURFACE-INITIATED ATOM TRANSFER RADICAL POLYMERIZATION

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Chinese Journal of Polymer Science 2008年第1期26卷 105-110页

作者： Lei, Hao Yu, Hai-yin Lu, Ying Lu, Xiao-long Xu, Zhi-kang Zhejiang Univ Minist Educ Inst Polymer Sci Hangzhou 310027 Peoples R China Zhejiang Univ Minist Educ Key Lab Macromol Synth & Functionalizat Hangzhou 310027 Peoples R China Tianjin Polytech Univ Inst Membrane Sci & Technol Ningbo 315211 Peoples R China

A novel approach for the surface modification of poly(vinylidene fluoride)(PVDF)membrane was successfully realized through alkaline treatment,UV-induced bromine addition,and followed by surface-initiated atom transfer radical polymerization(ATRP)of methyl methacrylate(MMA).Chemical changes on the PVDF membrane before and after modification were analyzed with attenuated total reflectance Fourier transform infrared spectroscopy(ATR/FT-IR)and X-ray photoelectron spectroscopy(XPS).Primary kinetic study revealed...

关键词： Poly(vinylidene fluoride) alkaline treatment Bromine addition Atom transfer radical polymerization

Mechanical Properties of Polypropylene Composites Reinforced with Macadamia Nutshell Fibers

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Journal of Renewable Materials 2019年第10期7卷 1047-1053页

作者： Joyce de P.Cipriano N.C.Zanini I.R.Dantas D.R.Mulinari Faculdade de Tecnologia/FAT/UERJ Rodovia Presidente Dutra km 298 Polo IndustrialResende27537-000Brazil Universidade Federal Fluminense Avenida dos Trabalhadores420Vila Santa CecíliaVolta Redonda27255-125Brazil

The use of natural fibers as an additive in polymeric matrices has attracted interest of the automotive industries,for its low cost,mechanical properties,biodegradability and ***,the hydrophilic nature of the fiber makes polymer compatibility *** surface treatments can be used to enhance the fiber/matrix *** the present work,polypropylene(PP)composites reinforced with fibers from macadamia nutshell were obtained and *** nutshell fibers were treated by an alkaline treatment with sodium hydroxide(NaOH 4%)to improve adhesion between fibers and *** were characterized by techniques of Scanning Electron Microscopy(SEM)and X-Ray Diffraction(XRD).The PP was mixed with the macadamia fibers(treated and untreated),in proportions of 5 and 10%(wt/wt)using a thermokinetic *** tensile,flexural and impact specimens(Pure PP and composites)were prepared by an injection molding process and tested for evaluation of mechanical *** results showed that the insertion of treated fibers in the PP matrix increased the stiffness of the ***,the composites reinforced with untreated fibers presented higher impact energy absorption when compared to composites reinforced with treated fibers.

关键词： Macadamia nutshell polypropylene alkaline treatment mechanical properties

alkaline modification of ZSM-5 catalysts for methanol aromatization： The effect of the alkaline concentration

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Frontiers of Chemical Science and Engineering 2015年第4期9卷 450-460页

作者： Zhenhao Wei Tengfei Xia Minghui Liu Qingsheng Cao Yarong Xu Kake Zhu Xuedong Zhu State Key Laboratory of Chemical Engineering School of Chemical Engineering East China University of Science and Technology Shanghai 200237 China Research Institute of Urumchi Petrochemical Company PetroChina Company Limited Urttmchi 830019 China

The effects of alkaline treatment on the physical properties of ZSM-5 catalysts and on their activities for methanol to aromatics conversion have been investigated. A mild alkaline treatment （0.2 and 0.3 mol/L NaOH） created mesopores in the parent zeolite with no obvious effect on acidity. The presence of mesopores gives the catalyst a longer lifetime and higher selectivity for aromatics. treatment with 0.4 mol/L NaOH decreased the number of Bronsted acid sites due to dealumination and desilication, which resulted in a lower deactivation rate. In addition, more mesopores were produced than with the mild alkaline treatment. As a result, the lifetime of the sample treated with 0.4 mol/L NaOH was almost five times that of the parent ZSM-5. treatment with a higher alkaline concentration （0.5 mol/L） greatly reduced the number of Bronsted acid sites and the number ofmicropores resulting in incomplete methanol conversion. When the alkalinetreated catalysts were washed with acid, some of the porosity was restored and a slight increase in selectivity for aromatics was obtained.

关键词： ZSM-5 alkaline treatment dealumination,desilication mesopores methanol aromatics

Highly dispersed iron species created on alkali-treated zeolite for ammonia SCR

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Progress in Natural Science:Materials International 2013年第5期23卷 493-500页

作者： Jing Ma Duan Weng Xiaodong Wu Zhichun Si Zhenwei Wu State Key Laboratory of New Ceramics & Fine Processing School of Materials Science and Engineering Yangtze Delta Region Institute of Tsinghua University Advanced materials institute Graduate School at ShenzhenTsinghua University

alkaline treatment using sodium hydroxide was introduced to obtain a hierarchical pore structure in H-ZSM-5 ***-exchanged zeolite catalysts were prepared by impregnation on the original and alkali-treated zeolites,and were evaluated for NOx reduction by NH3,NO oxidation,and NH3 oxidation *** highly dispersed iron species as active sites can be obtained by controlling the pore structure and particle size of ***,the Fe/ZSM-5 catalyst treated mildly by sodium hydroxide before iron exchange,which contains amounts of highly dispersed Fe species,obtains over80% NOx conversion at a wide temperature range of 250-500℃.

关键词： Fe/ZSM-5 alkaline treatment Brnsted acidity Iron dispersion NH3-SCR