scholarly journals Green degumming process of ramie fiber thermal effect and optimization

2019 ◽  
Vol 23 (4) ◽  
pp. 2447-2451 ◽  
Author(s):  
Guoliang Liu ◽  
Dan Tian ◽  
Bangze Zhou ◽  
Yumeng Zhang ◽  
Tao Xu ◽  
...  

Ramie is a kind of natural fibers, it requires degumming process before it can be used as a raw material for various applications. The traditional treatment uses alkali, which is not an environmentally friendly process. In this paper, ramie fibers are degummed using sodium percarbonate, which causes no any negative environmental problems, and its decomposition, hydrogen peroxide, is a clear liquid, it can be used as an oxidizer, bleaching agent and antiseptics for surface treatment of ramie fibers. Effect of temperature and concentration of sodium percarbonate on the degumming process are studied theoretically and verified experimentally. Finally an optimal degumming process is suggested for maximal weight ratio of degummed ramie fiber to raw bast.

2020 ◽  
Vol 15 ◽  
pp. 155892502094010
Author(s):  
Lifeng Cheng ◽  
Shengwen Duan ◽  
Xiangyuan Feng ◽  
Ke Zheng ◽  
Qi Yang ◽  
...  

Ramie ( Boehmeria nivea L.), a perennial herb, is an important bast fiber plant. Its fiber with the advantages of attractive luster, high tenacity, enhanced strength, and good microbial resistivity is well known as the queen of natural fibers. The abundant cellulose fibers in ramie raw materials are stuck tightly by gums consisting of pectic substances, hemicelluloses, and little lignin. The gum should remove from the ramie raw material through degumming process to separate fibers, unveil unique fiber properties, and improve fiber-spinning ability to fulfill textile requirements. Low degumming efficiency and high environmental pollution are the major problems hindering the utilization of ramie fibers. Ramie degumming involves the degradation of pectin and hemicelluloses, which requires chemical, physical, biological treatment, or a combination of several treatments. No stereotyped parameters of the given degumming method have been yet established for the extraction of textile-grade ramie fibers. This review evaluated integrated methodology involving chemical, physical, biological and biochemical methods to degum raw ramie and obtain textile-grade refined fibers.


2021 ◽  
pp. 004051752110449
Author(s):  
Huihui Wang ◽  
Tong Shu ◽  
Pandeng Li ◽  
Yun Bai ◽  
Mengxiong Xiang ◽  
...  

Ramie fiber is known as the “king of natural fibers,” and the key to its wide application is efficient and green manufacturing. Microbial degumming has gradually become a hot area of research due to its environmental protection and mild operating conditions. However, some gummy materials remain after microbial degumming. Xylan is the main component of residual gums; its acetylated branched chains create the space barrier that makes the removal of hemicellulose difficult during ramie degumming. An acetyl xylan esterase (AXE) was obtained from Bacillus pumilus and characterized to solve this problem. Its optimum temperature and pH were 35°C and 8.0, respectively, and it had good temperature and pH stability. These properties were consistent with the conditions of ramie degumming and they laid a foundation for the application of AXE in ramie degumming. Besides, an engineered strain with a high activity of AXE was constructed successfully on the basis of the wild-type degumming strain Pectobacterium carotovorum HG-49 and used for ramie degumming. The removal rate of hemicellulose and total gums by the engineered strain increased by 4.89% and 2.53%, respectively, compared with that of the wild-type strain. Moreover, the role of this AXE in ramie degumming was further proven by X-ray diffraction and scanning electron microscopy. This study showed that AXE played an important role in the removal of hemicellulose in the degumming process of ramie fibers, thus providing a promising degumming strategy for ramie and other bast fiber plants.


2020 ◽  
Vol 10 (2) ◽  
pp. 37-42
Author(s):  
Irwan Suriaman ◽  
Mardiyati ◽  
Jooned Hendrarsakti ◽  
Ari Darmawan Pasek

Industry 4.0 era materials used by entrepreneurs should be recycled, environmentally friendly, renewable with less chemical content. Indonesia as a tropical country has a large land area with the potential to produce the largest natural fiber in the world. One opportunity that can be applied to the utilization of natural fibers in air filters that currently use dominant materials is synthetic fibers. natural fiber has the advantage because it does not contain toxic chemicals, local raw materials, and is easily produced. This research will analyze the mechanical and morphological characteristics of biological fibers that have great potential as pre-filter raw material. Analysis of mechanical properties through tensile strength testing for single fibers and morphological analysis through scanning electron microscopy (SEM). Tensile testing was the results are; palm oil has a tensile strength of 620 MPa; 998 MPa and 213 MPa flax coconut fiber. For the morphological test results from SEM analysis for ramie fiber, it looks solid without fiber holes; The fibers appear to be many small fibers bound to one another while coir fibers have many pore holes in one observed fiber.


2013 ◽  
Vol 446-447 ◽  
pp. 384-389
Author(s):  
Wen Zhong Wang ◽  
Lei Zhao ◽  
Li Shan Fan

Study the influence of eri-silk degumming process for degumming results of 2709 alkaline protease; combined with the orthogonal experimental analysis of high degumming rate and breaking strength of the best eri-silk degumming process, and then compare the optimized extracted eri-silk with mulberry silk, virgin silk, cotton, wool and ramie fibers for their fineness, mechanical properties, and friction performance comparison. The results show that the 2709 alkaline protease can effectively remove silkgum, and that the amount of enzyme is the main factor affecting degumming rate; pH value is the main factors for the breaking strength. Comparing with other fibers, eri-silks average fineness is smaller, breaking strength and initial modulus tend to be larger, but their coefficient of variation also tend to be larger. Besides, eri-silkis breaking elongation is not as good as wool and silk, but better than other fibers. Natural silks dynamic and static coefficient of tangential impedance is lower in comparison with other natural fibers. Ramie has the largest tangential resistance factor. Among the natural silks, the eri-silks tangential impedance coefficient is greater than tussah and smaller than mulberry silk.


2018 ◽  
Vol 89 (17) ◽  
pp. 3653-3659 ◽  
Author(s):  
Yan Song ◽  
Wei Jiang ◽  
Kai Nie ◽  
Yuanming Zhang ◽  
Haoxi Ben ◽  
...  

Ramie is one of the most important fiber resources and it needs the degumming process to produce fibers. The traditional manufacturing process of ramie fibers requires a large amount of alkali, which causes serious environmental issues. This paper provides a novel path to manufacture ramie fibers without alkali. In this study, ramie bast was pretreated by steam explosion and then treated with deep eutectic solvent. The properties of ramie fibers prepared by the novel alkali-free method, including physical properties, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD), were compared with that produced by the traditional alkali process. Results showed that the fiber qualities, including residual gum content (4.68%), average fiber fineness (1419.99 Nm) and breaking tenacity (5.98 cN/dtex), were comparable with the traditional alkali process, which all meet the requirement of the relevant Chinese National Standards. The FTIR, SEM and XRD results all confirmed the degumming ability of the novel method to manufacture ramie fibers. Moreover, the novel method was proved to be eco-friendly. Taken together, these data indicate that the novel alkali-free method is green and effective in manufacturing ramie fibers.


2021 ◽  
Vol 15 (3) ◽  
pp. 3
Author(s):  
DEWI NANDYAWATI ◽  
DEA INDRIANI ASTUTI ◽  
NIKNIK NURHAYATI ◽  
ASEP RISWOKO ◽  
IS HELIANTI

Ramie fiber is a potential raw material to substitute imported raw materials such as cotton. Due to its higher hemicellulose content, ramie fiber required hydrolysis in a process called degumming. Enzymatic degumming is environmentally friendly compared to traditional process which using chemicals. Alkalithermophilic xylanase have high ability in hemicellulose hydrolysis. The production of xylanase was conducted by submerged fermentation of Bacillus halodurans CM1 in 20L bioreactor using Mamo and corncob medium with optimum conditions at 50°C, pH 9, 150 RPM and 1 vvm. The optimum specific activity of xylanase measured by Bailey method at 70°C and pH 9 is 475.41 U/mg. Xylanase was stable at 50°C, pH 9 and relatively stable to K+, Na2+, Co2+ and Ca2+ metal ions and Triton-X, Saba dan Tween-80 surfactants. Degumming process was carried out by immersing ramie fibers in formulated degumming solution with vlot 1:20 at 50°C, 150 RPM and 180 minutes. The enzymatic degumming process may substitute or reduce the use of chemicals due to its significant effect on ramie fiber quality. Enzymatic and chemical degumming process reduce the weight of Ramie Fiber to 7.23 %, and 7.72 %, slightly higher than enzymatic degumming 7.15%. Enzymatic degumming maintains tensile strength at 27.51 %. Whiteness index enhanced to 2.99% enzymatically and 3.49% chemically. Keywords: Bacillus halodurans CM1, enzymatic degumming, ramie fiber, textile industry, thermoalkaliphilic xylanase


Genes ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 842
Author(s):  
Chen ◽  
Rao ◽  
Wang ◽  
Zeng ◽  
Liu ◽  
...  

Ramie fibers, one of the most important natural fibers in China, are mainly composed of lignin, cellulose, and hemicellulose. As the high lignin content in the fibers results in a prickly texture, the lignin content is deemed to be an important trait of the fiber quality. In this study, the genetic basis of the fiber lignin content was evaluated, resulting in the identification of five quantitative trait loci (QTLs). Three genes, whole_GLEAN_10021050, whole_GLEAN_10026962, and whole_GLEAN_10009464 that were identified on the QTL regions of qLC7, qLC10, and qLC13, respectively, were found to be homologs of the Arabidopsis lignin biosynthetic genes. Moreover, all three genes displayed differential expression in the barks located in the top and middle parts of the stem, where lignin was not being synthesized and where it was being biosynthesized, respectively. Sequence comparison found that these three genes had wide variations in their coding sequences (CDSs) and putative promoter regions between the two parents, especially the MYB gene whole_GLEAN_10021050, whose protein had insertions/deletions of five amino acids and substitutions of two amino acids in the conserved domain. This evidence indicates that these three genes are potentially involved in lignin biosynthesis in ramie fibers. The QTLs identified from this study provide a basis for the improvement of lignin content and fiber quality in ramie breeding. The characterization of the three candidate genes here will be helpful for the future clarification of their functions in ramie.


2018 ◽  
Vol 27 (4) ◽  
pp. 096369351802700 ◽  
Author(s):  
Mehmet Önal ◽  
Gökdeniz Neşer

Glass reinforced polyester (GRP), as a thermoset polymer composites, dominates boat building industry with its several advantages such as high strength/weight ratio, cohesiveness, good resistance to environment. However, proper recovering and recycling of GRP boats is became a current environmental requirement that should be met by the related industry. In this study, to propose in a cost effective and environmentally friendly way, Life Cycle Assessment (LCA) has been carried out for six scenarios include two moulding methods (namely Hand Lay-up Method, HLM and Vacuum Infusion Method, VIM) and three End-of-Life (EoL) alternatives(namely Extruding, Incineration and Landfill) for a recreational boat's GRP hulls. A case study from raw materials purchasing phase to disposal/recycling stages has been established taking 11 m length GRP boat hull as the functional unit. Analysis show that in the production phase, the impacts are mainly due to the use of energy (electricity), transport and raw material manufacture. Largest differences between the methods considered (HLM and VIM) can be observed in the factors of marine aquatic ecotoxicity and eutrophication while the closest ones are abiotic depletion, ozon layer depletion and photochemical oxidation. The environmental impact of VIM is much higher than HLM due to its higher energy consumption while vacuum infusion method has lower risk than hand lay-up method in terms of occupational health by using less raw material (resin) in a closed mold. In the comparison of the three EoL techniques, the mechanical way of recycling (granule extruding) shows better environmental impacts except terrestrial ecotoxicity, photochemical oxidation and acidification. Among the EoL alternatives, landfill has the highest environmental impacts except ‘global warming potential’ and ‘human toxicity’ which are the highest in extrusion. The main cause of the impacts of landfill is the transportation needs between the EoL boats and the licenced landfill site. Although it has the higher impact on human toxicity, incineration is the second cleaner alternative of EoL techniques considered in this study. In fact that the similar trend has been observed both in production and EoL phases of the boat. It is obvious that using much more renewable energy mix and greener transportation alternative can reduce the overall impact of the all phases considerably.


Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1311 ◽  
Author(s):  
Fabio da Costa Garcia Filho ◽  
Fernanda Santos da Luz ◽  
Lucio Fabio Cassiano Nascimento ◽  
Kestur Gundappa Satyanarayana ◽  
Jaroslaw Wieslaw Drelich ◽  
...  

Natural lignocellulosic fibers and corresponding fabrics have been gaining notoriety in recent decades as reinforcement options for polymer matrices associated with industrially applied composites. These natural fibers and fabrics exhibit competitive properties when compared with some synthetics such as glass fiber. In particular, the use of fabrics made from natural fibers might be considered a more efficient alternative, since they provide multidirectional reinforcement and allow the introduction of a larger volume fraction of fibers in the composite. In this context, it is important to understand the mechanical performance of natural fabric composites as a basic condition to ensure efficient engineering applications. Therefore, it is also important to recognize that ramie fiber exhibiting superior strength can be woven into fabric, but is the least investigated as reinforcement in strong, tough polymers to obtain tougher polymeric composites. Accordingly, this paper presents the preparation of epoxy composite containing 30 vol.% Boehmeria nivea fabric by vacuum-assisted resin infusion molding technique and mechanical behavior characterization of the prepared composite. Obtained results are explained based on the fractography studies of tested samples.


2016 ◽  
Vol 23 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Guijun Xian ◽  
Peng Yin ◽  
Innocent Kafodya ◽  
Hui Li ◽  
Wei-lun Wang

AbstractA durability study of a ramie fiber fabric reinforced phenolic resin (RFRP) plate under 50%, 85%, and 98% relative humidity for 6 months at room temperature was performed. Water absorption and desorption, tensile and short beam shear strengths of the RFRP plates were investigated as a function of exposure time. RFRP samples show strong hydrophilic characteristics and the saturated water content varies from 0.73% to 4.5% with relative humidity ranging from 50% to 98%. After 6 months of exposure to 98% relative humidity, an abnormal extra amount of moisture was absorbed, which may have resulted from cracks in the resin matrix or from debonding between fiber and resin due to swelling of the fibers with high moisture content. It was found that the tensile modulus is more susceptible to moisture uptake, which is ascribed to the degradation of ramie fibers with the water ingress. An approximate linearity between the mechanical properties and the moisture content is observed if the abnormal extra water uptake is neglected. Both tensile and short beam shear strengths of the RFRP samples recovered remarkably when samples were fully dried at 60°C, indicating a low degree of permanent degradation occurred due to the exposure.


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