scholarly journals Influence of Hydrolysis Conditions on Characteristics of Nanocrystalline Cellulose Extracted from Ramie Fibers by Hydrochloric Acid Hydrolysis

2020 ◽  
Author(s):  
Kusmono Kusmono ◽  
Dimas Abdillah Akbar
Keyword(s):  
Thermal Stability ◽  
Hydrochloric Acid ◽  
Acid Hydrolysis ◽  
Acid Concentration ◽  
Crystallinity Index ◽  
Hydrochloric Acid Concentration ◽  
Hydrolysis Time ◽  
Study Results ◽  
Ramie Fibers ◽  
Hydrolysis Conditions

Abstract Nanocrystalline celluloses (NCCs) were successfully extracted from ramie fibers using chemical pretreatments followed by hydrochloric acid hydrolysis. The effects of acid concentration and hydrolysis time on the characteristics of NCCs were investigated in this study. Results showed that the optimal hydrolysis conditions were found to be 6 M hydrochloric acid concentration at 45 °C for 70 min. The obtained NCC had a rod like-shape with an average of 8.07 nm in diameter, 158.51 nm in length, 22.37 in aspect ratio, 89.61% in the crystallinity index, and 5.81 nm in crystallite size. The higher crystallinity and thermal stability were exhibited by NCCs compared to both raw fibers and chemically purified cellulose. The hydrolysis time had a significant effect on crystallinity and thermal stability. The crystallinity index and thermal stability of NCCs were obtained to decrease with increasing hydrolysis time.

Extraction and Characterization of Nanocrystalline Cellulose (NCC) from Ramie Fiber by Hydrochloric Acid Hydrolysis

2020 ◽  
Vol 867 ◽  
pp. 109-116
Author(s):  
Dimas Abdillah Akbar ◽  
Kusmono ◽  
Muhammad Waziz Wildan ◽  
Mochammad Noer Ilman
Keyword(s):  
Hydrochloric Acid ◽  
Acid Hydrolysis ◽  
Acid Concentration ◽  
Natural Fibers ◽  
Crystallinity Index ◽  
High Strength ◽  
Extraction Process ◽  
Nanocrystalline Cellulose ◽  
Ramie Fiber ◽  
Cellulose Content

The present study investigates the structural, crystallinity index, crystallite size, morphological, and the dimension of Nanocrystalline Cellulose (NCC) extracted from ramie fiber by hydrochloric acid-hydrolysis. NCC was chosen because it has high strength and modulus compared to other natural materials. Ramie fiber was chosen because it has high cellulose content and abundant in Indonesia. The other reason is ramie has a high crystallinity index compared to other natural fibers. The extraction process was carried out into two steps: cellulose purification then followed by hydrochloric acid hydrolysis. The characterizations of extracted NCCs were conducted through Fourier-Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), and Particle Size Analyzer (PSA). The focus of this research was to study the effect of acid concentration on the characteristics of extracted NCCs. The results show that NCCs could be extracted through hydrolysis using hydrochloric acid. Morphological analysis by TEM shows the formation of rod-like shaped NCCs. Hydrolysis by hydrochloric acid does not affect the chemical compound of cellulose. It was found that during hydrolysis, the higher acid concentration being employed had resulted in smaller dimension of NCCs and decreasing crystallinity index.

Study on Optimizate Isolation and Purification Technology of the Reed Ethanol Lignin

2013 ◽  
Vol 726-731 ◽  
pp. 3109-3112
Author(s):  
Li Chun Zhou ◽  
Qing Wei Ping ◽  
Jian Zhang ◽  
Hai Qiang Shi
Keyword(s):  
Enzymatic Hydrolysis ◽  
Hydrochloric Acid ◽  
Acid Hydrolysis ◽  
Acid Concentration ◽  
Hydrochloric Acid Concentration ◽  
Isolation And Purification ◽  
Waste Liquor ◽  
Step Procedure ◽  
Hydrolysis Temperature ◽  
Enzyme Dosage

Ethanol pulping is a kind of solvent pulping technology. The utilization of lignin in waste liquor can reduce pollution and increase high value of product. The lignin in the waste liquor could be isolated by adding water in the system after standing for several hours and purified by enzymatic and acidic hydrolysis two-step procedure. Results showed that the optimized purification conditions are as follows, enzyme dosage is 0.004g/g (to oven dry lignin), enzymatic buffer pH is 5, enzymatic hydrolysis temperature is 30°C, and hydrochloric acid concentration of acid hydrolysis is 0.055mol/L. The lignin purity is 91.61%, and the yield is 81.89%.

scholarly journals Cellulose Nanocrystals from Fibers of Macauba (Acrocomia Aculeata) and Gravata (Bromelia Balansae) from Brazilian Pantanal

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1785 ◽  
Author(s):  
Ana Carolina Corrêa ◽  
Vitor Brait Carmona ◽  
José Alexandre Simão ◽  
Fabio Galvani ◽  
José Manoel Marconcini ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Acid Hydrolysis ◽  
Cellulose Nanocrystals ◽  
Cellulose Degradation ◽  
Crystallinity Index ◽  
Palm Tree ◽  
Cellulose Content ◽  
Hydrolysis Time ◽  
Brazilian Pantanal

Cellulose nanocrystals (CNC) were obtained from macauba and gravata fibers. Macauba (or Bocaiuva) is a palm tree found throughout most of Brazil and Gravata is an abundant kind of bromelia with 1–2m long leaves, found in Brazilian Pantanal and Cerrado. The raw fibers of both fibers were mercerized with NaOH solutions and bleached; they were then submitted to acid hydrolysis using H2SO4 at 45 °C, varying the hydrolysis time from 15 up to 75 min. The fibers were analyzed by X-ray diffraction (XRD), FTIR Spectroscopy, scanning electron microscopy (SEM) and thermal stability by thermogravimetric analysis (TG). XRD patterns did not present changes in the crystal structure of cellulose after mercerization, but it was observed a decrease of hemicellulose and lignin contents, and consequently an increase of cellulose content with the increase of NaOH solution concentration in the mercerization. After acid hydrolysis, the cellulose nanocrystals (CNC) were also analyzed by transmission electron microscopy (TEM) which showed an acicular or rod-like aspect and nanometric dimensions of CNC from both fibers, but the higher values of aspect ratio (L/D) were found on CNC obtained from gravata after 45 min of acid hydrolysis. The mercerization and subsequent bleaching of fibers influenced the crystallinity index and thermal stability of the resulting CNC, but their properties are mainly influenced by the hydrolysis time, i. e., there is an increase in crystallinity and thermal stability up to 45 min of hydrolysis, after this time, both properties decrease, probably due to the cellulose degradation by the sulfuric acid.

scholarly journals Synthesis of Cellulose Nanocrystals (CNCs) from Brewer’s Spent Grain Using Acid Hydrolysis: Characterization and Optimization

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Bisrat Yihun Matebie ◽  
Belachew Zegale Tizazu ◽  
Aseel A. Kadhem ◽  
S. Venkatesa Prabhu
Keyword(s):  
Acid Hydrolysis ◽  
Acid Concentration ◽  
Cellulose Nanocrystals ◽  
Average Particle Size ◽  
Cellulose Nanocrystal ◽  
Average Particle ◽  
Hydrolysis Time ◽  
Solid Ratio ◽  
Spent Grain ◽  
Hydrolysis Conditions

This study is aimed at utilizing brewery’s spent grain (BSG) byproduct for the synthesis of cellulose nanocrystals (CNCs) using acid hydrolysis and optimizing the hydrolysis parameters (hydrolysis time, temperature, liquid-solid ratio, and acid concentration). Alkali and bleaching treatment were done to remove hemicellulose and lignin from BSG. Optimization process was performed using central composite design (CCD) to obtain optimum value of cellulose nanocrystal (CNC) yield. The maximum cellulose nanocrystal (CNC) yield of 43.24% was obtained at optimum hydrolysis conditions of 50°C, 51 wt% acid concentration, 41 min, and liquid-solid ratio of 19 ml/g. The raw brewery spent grain; alkali-treated fiber, bleached fiber, and obtained CNC were characterized using scanning electron microscopy (SEM), XRD, particle analyzer, FTIR, and differential scanning calorimeter (DSC). The characterization results indicated that the obtained cellulose nanocrystal (CNC) has rod-like whisker shape with crystallinity of 76.3% and an average particle size of 309.4 nm.

Experimental Study on Concentrating Scandium by Leaching from Associated Scandium Ore

2013 ◽  
Vol 734-737 ◽  
pp. 1033-1036
Author(s):  
Gui Fang Zhang ◽  
Peng Yan ◽  
Qing Rong Yang
Keyword(s):  
Experimental Study ◽  
Particle Size ◽  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Hydrochloric Acid Concentration ◽  
Leaching Rate ◽  
Optimal Conditions ◽  
Research Results ◽  
Solid Ratio ◽  
Leaching Residue

Based on the benefication of the complex silicate ore containing scandium, the research about aid-leaching agent used in the leaching of the scandium concentrate was been conducted. And the suitable leaching agent and aid-leaching agent which the useful ions entered into leaching liquid and the harmful ions were kept in leaching residue were been found according to the experiment results. For the scandium of sample existed various complex silicate ore as isomorphism form, the research has adopted hydrochloric acid with aid-leaching agent to dissociate the silicate ore and make scandium entering into solution. The research results has shown that the scandium leaching rate could reach 92.06% under the optimal conditions which the hydrochloric acid concentration is 22.8%, the dosage of aid leaching agent is 6%, liquid solid ratio is 4:1, particle size of leaching material totally is less than 0.15mm and leaching time is 8h.

Effects of high hydrochloric acid concentration on aniline chemical polymerization

Polymer ◽  
1997 ◽  
Vol 38 (20) ◽  
pp. 5247-5250 ◽  
Author(s):  
Gustavo M. Morales ◽  
Marcos Llusa ◽  
Maria C. Miras ◽  
Cesar Barbero
Keyword(s):  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Hydrochloric Acid Concentration ◽  
Chemical Polymerization
Sign in / Sign up

Export Citation Format

Share Document