This paper work involves bunch experiments to investigate the effect of contact time, pH, and adsorbent dose on the extent of adsorption by bio-composites. Adsorption capacity of Chromium (VI) onto chitosan coated wit...This paper work involves bunch experiments to investigate the effect of contact time, pH, and adsorbent dose on the extent of adsorption by bio-composites. Adsorption capacity of Chromium (VI) onto chitosan coated with banana and areca fiber was investigated in a batch system by considering the effects of various parameters like contact time, initial concentration, pH and adsorbent dose. The chitosan and fibers (banana and areca) were then cross-linked with glutaraldehyde to remove chromium [Cr (VI)] from water via static adsorption. It was found that optimum chromium absorption capacity of chitosan was assessed at pH of 2.5 to 4.5 and contact time of 30 to 180 minutes for raw banana and areca fiber and for chitosan treated banana & areca fiber. Though optimum adsorption of chromium of chitosan was measured 34.17 ppm (85.42%) from a 100 ml solution containing 40 parts per million (ppm) of Cr (VI) at 120 minutes, pH of 3.0 and 120 milligram (mg) adsorbent dose size, use of composite will be more favorable in the point of environmental concern as well as low cost because chitosan preparation is comparatively costly then banana and areca fiber. On the other hand, untreated banana and areca fiber optimum adsorption of chromium measured 3.65 ppm (9.1%) at 180 min and, pH of 4.5 and 140 mg adsorbent dose size and 3.76 ppm (9.4%) at 180 min, pH of 4.5 and 160 mg adsorbent dose size respectively. In case of chitosan treated banana fiber, it was observed that adsorption was increased from 17.664 to 30.057 (75.14%). On the other hand, for areca fiber with chitosan, it was observed that adsorption was increased from 21.664 to 30.156 (75.39%) ppm. The Langmuir and Freundlich adsorption models were used for the mathematical description of the adsorption of chromium ion onto composites and it was found that the Langmuir adsorption isotherm was more fitted models which mean that a monolayer adsorption surface was created. After analyzing from IBM SPSS 25 software, we got the standard deviation value of adsorbed Cr by raw chitosan, untreated banana and areca of pH test results were 9.399, 1.072, 0.728 ppm, time test results were 2.163, 0.859, 0.896 ppm and adsorbent dose test results were 6.588, 0.966, 1.211 ppm correspondingly. The standard deviation results of pH, time and amount of treated banana fiber test results were 1.831, 2.693 and 5.469 ppm congruently. On the other hand, the standard deviation results of pH, time and amount of treated areca fiber test results were 3.293, 2.673 and 4.152 ppm individually. Fourier transform infrared (FT-IR) spectroscopy analysis indicated that both amino and hydroxyl groups of chitosan, banana and areca fiber were engaged in the adsorption.展开更多
The demand for natural fibers has always been high due to their unique characteristics like strength, lightweight, availability, bio-degradability, etc. In every phase of life, from clothing to technical textiles, nat...The demand for natural fibers has always been high due to their unique characteristics like strength, lightweight, availability, bio-degradability, etc. In every phase of life, from clothing to technical textiles, natural fibers are used. Water absorption of fibers is considered really important in many aspects, e.g., Sportech, Medtech, Geotech, etc. This work analyses water absorption of raw and alkali-treated cotton, arecas, pineapple leaves, and banana fibers. Fibers were scoured with different concentrations of alkali (2, 4, 6 gm/L NaOH), washed and neutralized with the dilute acetic acid solution, then dried. Later on, the fiber samples were immersed into distilled water, and water absorption percentages of the fibers were determined every 10 minutes within 1 hour in total. It appeared that at untreated conditions, the areca fiber has the highest water absorption capacity compared to the other fibers. Alkali-treated cotton shows the highest water absorption, and areca fibers show approximately 60% water absorption of cotton.展开更多
In order to mitigate the risks stemming from the utilization of mineral and synthetic organic substances,consensus exists in the literature that additional efforts should be devoted to the identification of adequate e...In order to mitigate the risks stemming from the utilization of mineral and synthetic organic substances,consensus exists in the literature that additional efforts should be devoted to the identification of adequate equivalent natural(ecological)materials.This work presents the outcomes of a preliminary study where the physical,mechanical,chemical and thermal properties of natural fibers have been considered.Initially,areca,and materials such as Moroccan doum and jute are considered.As a case study,a brake pad based on natural fibers is critically assessed.展开更多
Natural fibers can play a major role in composite industry due to its renewable, biodegradable, and eco-friendly properties. Areca Fruit Husk （AFH） is rich in fiber, but is wasted in large quantity from tobacco indu...Natural fibers can play a major role in composite industry due to its renewable, biodegradable, and eco-friendly properties. Areca Fruit Husk （AFH） is rich in fiber, but is wasted in large quantity from tobacco industries. Comprehensive characterization of AFH fiber is done to examine its morphological, physical, mechanical, chemical and thermal properties. High cellulose content of the fiber （57.35 wt%） provides better tensile strength （231.66 MPa） whereas the porous surface morphology （40.8 %） ensures better bonding with the matrix. Moreover, the low density of the fiber （0.78 g.cm^-3） makes it an attractive alternative for hazardous synthetic fibers. The semi-crystalline nature and large crystalline size of the fiber reduce the water absorption char- acteristics. The thermo gravimetric analysis confirms its stability up to 240℃, which is higher than the polymerization tem- perature. The results confirm the potential of AFH fibers as a reinforcement in bio-reinforced polymer composites for automo- tive and structural applications.展开更多
文摘This paper work involves bunch experiments to investigate the effect of contact time, pH, and adsorbent dose on the extent of adsorption by bio-composites. Adsorption capacity of Chromium (VI) onto chitosan coated with banana and areca fiber was investigated in a batch system by considering the effects of various parameters like contact time, initial concentration, pH and adsorbent dose. The chitosan and fibers (banana and areca) were then cross-linked with glutaraldehyde to remove chromium [Cr (VI)] from water via static adsorption. It was found that optimum chromium absorption capacity of chitosan was assessed at pH of 2.5 to 4.5 and contact time of 30 to 180 minutes for raw banana and areca fiber and for chitosan treated banana & areca fiber. Though optimum adsorption of chromium of chitosan was measured 34.17 ppm (85.42%) from a 100 ml solution containing 40 parts per million (ppm) of Cr (VI) at 120 minutes, pH of 3.0 and 120 milligram (mg) adsorbent dose size, use of composite will be more favorable in the point of environmental concern as well as low cost because chitosan preparation is comparatively costly then banana and areca fiber. On the other hand, untreated banana and areca fiber optimum adsorption of chromium measured 3.65 ppm (9.1%) at 180 min and, pH of 4.5 and 140 mg adsorbent dose size and 3.76 ppm (9.4%) at 180 min, pH of 4.5 and 160 mg adsorbent dose size respectively. In case of chitosan treated banana fiber, it was observed that adsorption was increased from 17.664 to 30.057 (75.14%). On the other hand, for areca fiber with chitosan, it was observed that adsorption was increased from 21.664 to 30.156 (75.39%) ppm. The Langmuir and Freundlich adsorption models were used for the mathematical description of the adsorption of chromium ion onto composites and it was found that the Langmuir adsorption isotherm was more fitted models which mean that a monolayer adsorption surface was created. After analyzing from IBM SPSS 25 software, we got the standard deviation value of adsorbed Cr by raw chitosan, untreated banana and areca of pH test results were 9.399, 1.072, 0.728 ppm, time test results were 2.163, 0.859, 0.896 ppm and adsorbent dose test results were 6.588, 0.966, 1.211 ppm correspondingly. The standard deviation results of pH, time and amount of treated banana fiber test results were 1.831, 2.693 and 5.469 ppm congruently. On the other hand, the standard deviation results of pH, time and amount of treated areca fiber test results were 3.293, 2.673 and 4.152 ppm individually. Fourier transform infrared (FT-IR) spectroscopy analysis indicated that both amino and hydroxyl groups of chitosan, banana and areca fiber were engaged in the adsorption.
文摘The demand for natural fibers has always been high due to their unique characteristics like strength, lightweight, availability, bio-degradability, etc. In every phase of life, from clothing to technical textiles, natural fibers are used. Water absorption of fibers is considered really important in many aspects, e.g., Sportech, Medtech, Geotech, etc. This work analyses water absorption of raw and alkali-treated cotton, arecas, pineapple leaves, and banana fibers. Fibers were scoured with different concentrations of alkali (2, 4, 6 gm/L NaOH), washed and neutralized with the dilute acetic acid solution, then dried. Later on, the fiber samples were immersed into distilled water, and water absorption percentages of the fibers were determined every 10 minutes within 1 hour in total. It appeared that at untreated conditions, the areca fiber has the highest water absorption capacity compared to the other fibers. Alkali-treated cotton shows the highest water absorption, and areca fibers show approximately 60% water absorption of cotton.
文摘In order to mitigate the risks stemming from the utilization of mineral and synthetic organic substances,consensus exists in the literature that additional efforts should be devoted to the identification of adequate equivalent natural(ecological)materials.This work presents the outcomes of a preliminary study where the physical,mechanical,chemical and thermal properties of natural fibers have been considered.Initially,areca,and materials such as Moroccan doum and jute are considered.As a case study,a brake pad based on natural fibers is critically assessed.
文摘Natural fibers can play a major role in composite industry due to its renewable, biodegradable, and eco-friendly properties. Areca Fruit Husk （AFH） is rich in fiber, but is wasted in large quantity from tobacco industries. Comprehensive characterization of AFH fiber is done to examine its morphological, physical, mechanical, chemical and thermal properties. High cellulose content of the fiber （57.35 wt%） provides better tensile strength （231.66 MPa） whereas the porous surface morphology （40.8 %） ensures better bonding with the matrix. Moreover, the low density of the fiber （0.78 g.cm^-3） makes it an attractive alternative for hazardous synthetic fibers. The semi-crystalline nature and large crystalline size of the fiber reduce the water absorption char- acteristics. The thermo gravimetric analysis confirms its stability up to 240℃, which is higher than the polymerization tem- perature. The results confirm the potential of AFH fibers as a reinforcement in bio-reinforced polymer composites for automo- tive and structural applications.
