scholarly journals Kinetics study the decomposition of the cellulose into cellulose nanocrystals by hydrothermal with hydrochloric acid catalyst

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Zulnazri Zulnazri ◽  
Rozanna Dewi ◽  
Sulhatun Sulhatun ◽  
Nasrun Nasrun
Keyword(s):  
Hydrochloric Acid ◽  
Cellulose Nanocrystals ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Reaction Rate Constant ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Reaction Rate Constants ◽  
Ft Ir

The aim of this study was to hydrolyzed cellulose nanocrystals as cellulose-based biomass residues from oil palm by using hydrochloric acid under hydrothermal conditions. The characterization of cellulose nanocrystals was determined by FT-IR spectroscopy and X- ray diffraction. The infrared spectroscopy showed there has been a removal of lignin and hemicellulose in the spectrum. Crystallinity which reaches 78.59% was obtained by hydrolysis using hydrochloric acid catalyst 3 mol/L with a reaction time of 1 hour. Based on the graph of -ln CA/CA0 vs. time obtained that Cellulose nanocrystals forming reaction is of first order. The reaction rate constants to the formation of glucose (k2) is greater than the reaction rate constant to the formation of Cellulose nanocrystals (k1), which indicates that the phase of slow reaction is the reaction of the most influential on the overall reaction rate, the reaction of the formation of Cellulose nanocrystals.

PENGARUH KONSENTRASI KATALIS ASAM DAN KECEPATAN PENGADUKAN PADA HIDROLISIS SELULOSA DARI AMPAS BATANG SORGUM MANIS

EKUILIBIUM ◽  
2013 ◽  
Vol 12 (1) ◽  
Author(s):  
Enny Kriswiyanti
Keyword(s):  
Hydrochloric Acid ◽  
Sweet Sorghum ◽  
Reaction Rate ◽  
Acid Catalyst ◽  
Agitation Speed ◽  
First Order ◽  
Reaction Rate Constants ◽  
Glucose Levels ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

<p>Abstract : Sweet sorghum stem residues contains high enough cellulose (36.92%)so it can be<br />hydrolyzed to glucose. In this research, hydrolysis of cellulose is carried out using hydrochloric<br />acid catalyst. This research aims to determine the effect of acid catalyst concentration and<br />agitation speed on the resulting reduction of glucose levels and determine the reaction rate<br />constant of hydrolysis of sweet sorghum stem residues. The observed variables were the<br />concentration of hydrochloric acid catalyst (0.5 N, 1 N, 1.5 N, 2 N) and the agitation speed (150<br />rpm, 200 rpm, 250 rpm, 300 rpm). Glucose samples were analyzed by using the Lane-Eynon<br />method. Data analysis showed the higher concentration of hydrochloric acid (HCl) and the<br />agitation speed, the levels of reduced glucose that is formed is also higher. In this study by<br />assuming a first order reaction, the reaction rate constants obtained at variable concentrations of<br />hydrochloric acid catalyst ranged from 0.0010 to 0.0033 / minute and at agitation speeds variable<br />ranged from 0.0023 to 0.0030 / minute.<br />Keywords : sweet sorghum stem residues, hydrochloric acid, hydrolysis, cellulose</p>

HIDROLISA PATI DARI KULIT SINGKONG (VARIABEL RATIO BAHAN DAN KONSENTRASI ASAM)

EKUILIBIUM ◽  
2013 ◽  
Vol 12 (1) ◽  
Author(s):  
Endang Mastuti
Keyword(s):  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Reaction Rate ◽  
Animal Feed ◽  
Economic Value ◽  
Acid Catalyst ◽  
Operating Conditions ◽  
Starch Hydrolysis ◽  
Reaction Rate Constants ◽  
Cassava Peel

<p>Abstract: Cassava peel is generally used as animal feed and sometimes just thrown away. To<br />increase the economic value of cassava peels used as alternative materials to manufacture<br />glucose by hydrolysis. This study aims to determine the effect of material and the concentration<br />ratio of acid to the peel of cassava starch hydrolysis of the resulting reduction of glucose and<br />starch hydrolysis reaction rate constants of the cassava peel with hydrochloric acid catalyst.<br />Variables remained in the study was 250 ml volume of cooking and temperature 95<br />C (boiling<br />temperature). Variable is the ratio of materials that were reviewed (30 gr, 40 gr, 50 gr and 60 gr)and acid concentration (0.05 N, 0.1 N; 0.15 N; and 0.2 N). Glucose samples were analyzed by<br />using the Lane-Eynon. Data analysis showed the material and the larger the ratio of acid<br />concentration, the glucose formed higher. So also with increasing reaction time, glucose is<br />formed also higher. Operating conditions which result in maximum glucose in the ratio 5:1<br />material and acid concentration 0.2 N. In this study the reaction of first order reaction rate<br />constants obtained in ratio of materials from 0.0116 to 0.0172/min and at variable acid<br />concentrations from 0.0157 to 0.0252/min.<br />Keywords: Cassava peel, hydrolysis, hydrochloric acid<br />o</p>

Hydrothermal Synthesis and Characterization of Cu-Saponite

2013 ◽  
Vol 669 ◽  
pp. 124-130 ◽  
Author(s):  
Xian Mei Xie ◽  
Lian Duan ◽  
Xing Yu Cui ◽  
Jian Ming Zhang ◽  
Jie Xing
Keyword(s):  
Hydrothermal Synthesis ◽  
Raw Materials ◽  
Copper Nitrate ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Hydrothermal Temperature ◽  
Synthesis Conditions ◽  
Ft Ir ◽  
Adsorption Desorption

Hydrothermal synthesis of Cu-saponite was achieved using copper nitrate and sodium silicate as the raw materials. The mixtures of starting materials were treated under hydrothermal conditions at 60–230°C for 6–48h. The effect of different synthetic parameters such as hydrothermal temperature and hydrothermal time on the structure development of Cu-saponite was discussed. All the samples were characterized by X-ray diffraction (XRD), FT-IR, scanning electron microscopy (SEM) and nitrogen physisorption techniques. The results of the study showed that the obtained Cu-saponite exhibited better crystallinity at 200°C for 36h. Both increasing hydrothermal temperature and the duration of hydrothermal treatment yielded better crystallized Cu-saponite as determined by XRD. SEM micrographs revealed plate-like shape of the synthetic Cu-saponite. The results of nitrogen physisorption measurements showed different synthesis conditions resulted in different adsorption-desorption isotherms.

scholarly journals Synthesis and Structural Characterization of (E)-4-[(2-Hydroxy-3-methoxybenzylidene)amino]butanoic Acid and Its Novel Cu(II) Complex

Molbank ◽  
10.3390/m1179 ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. M1179
Author(s):  
Eleftherios Halevas ◽  
Antonios Hatzidimitriou ◽  
Barbara Mavroidi ◽  
Marina Sagnou ◽  
Maria Pelecanou ◽  
...  
Keyword(s):  
Schiff Base ◽  
Gamma Aminobutyric Acid ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
Polymeric Compound ◽  
Bridging Ligands ◽  
1H And 13C Nmr ◽  
One Dimensional ◽  
Ft Ir

A novel Cu(II) complex based on the Schiff base obtained by the condensation of ortho-vanillin with gamma-aminobutyric acid was synthesized. The compounds are physico-chemically characterized by elemental analysis, HR-ESI-MS, FT-IR, and UV-Vis. The complex and the Schiff base ligand are further structurally identified by single crystal X-ray diffraction and 1H and 13C-NMR, respectively. The results suggest that the Schiff base are synthesized in excellent yield under mild reaction conditions in the presence of glacial acetic acid and the crystal structure of its Cu(II) complex reflects an one-dimensional polymeric compound. The molecular structure of the complex consists of a Cu(II) ion bound to two singly deprotonated Schiff base bridging ligands that form a CuN2O4 chelation environment, and a coordination sphere with a disordered octahedral geometry.

One Step Synthesis and Characterization of Zirconia-Graphene Composites

2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Composite ◽  
Transmission Electron ◽  
One Step ◽  
Ft Ir ◽  
Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

Characterization of SrBi2Nb2O9 Thin Films Prepared by Sol Gel Technique

1996 ◽  
Vol 459 ◽  
Author(s):  
E. Ching-Prado ◽  
W. Pérez ◽  
A. Reynés-Figueroa ◽  
R. S. Katiyar ◽  
D. Ravichandran ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Band ◽  
Sol Gel ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Ft Ir ◽  
Gel Technique ◽  
High Degree ◽  
First Time

ABSTRACTThin films of SrBi2Nb2O9 (SBN) with thicknesses of 0.1, 0.2, and 0.4 μ were grown by Sol-gel technique on silicon, and annealed at 650°C. The SBN films were investigated by Raman scatering for the first time. Raman spectra in some of the samples present bands around 60, 167, 196, 222, 302, 451, 560, 771, 837, and 863 cm−1, which correspond to the SBN formation. The study indicates that the films are inhomogeneous, and only in samples with thicknesses 0.4 μ the SBN material was found in some places. The prominent Raman band around 870 cm−1, which is the A1g mode of the orthorhombic symmetry, is assigned to the symmetric stretching of the NbO6 octahedrals. The frequency of this band is found to shift in different places in the same sample, as well as from sample to sample. The frequency shifts and the width of the Raman bands are discussed in term of ions in non-equilibrium positions. FT-IR spectra reveal a sharp peak at 1260 cm−1, and two broad bands around 995 and 772 cm−1. The bandwidths of the latter two bands are believed to be associated with the presence of a high degree of defects in the films. The experimental results of the SBN films are compared with those obtained in SBT (T=Ta) films. X-ray diffraction and SEM techniques are also used for the structural characterization.

Synthesis and Structural Characterization of a Novel Composite Modified Starch

2011 ◽  
Vol 396-398 ◽  
pp. 1180-1183
Author(s):  
He Ping Li ◽  
Hu Qiang Lv ◽  
Yao Zhang ◽  
Yong Zhe Yang
Keyword(s):  
Structural Characterization ◽  
Orthogonal Experiment ◽  
Acid Catalyst ◽  
Chloroacetic Acid ◽  
Normal Pressure ◽  
Modified Starch ◽  
Optimum Conditions ◽  
X Ray Diffraction ◽  
Mass Fractions

In the normal pressure and presence of catalyst, a novel composite modified starch or functional surfactant was synthesized by using the cassava starch as the main feedstock through the alkalization, etherification and oxidation etc.. The degree of substitution was up to 1.21. Based on the orthogonal experiment and computer-aid methods, the optimum conditions were resulted as follows: the mass fractions(vs. dry starch) of chloroacetic acid, catalyst and oxidant were 32%, 0.01% and 1.14% respectively, and the reaction temperature of etherification was at 50°C for 4.1h. The structural characterization of the composite modified starch was determined by IR and X-ray diffraction.

scholarly journals Dual Light- and pH-Responsive Composite of Polyazo-Derivative Grafted Cellulose Nanocrystals

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1725 ◽  
Author(s):  
Xiaohong Liu ◽  
Ming Li ◽  
Xuemei Zheng ◽  
Elias Retulainen ◽  
Shiyu Fu
Keyword(s):  
Cellulose Nanocrystals ◽  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
X Ray Diffraction ◽  
Responsive Materials ◽  
X Ray ◽  
Ph Response ◽  
Transmission Electron ◽  
Ft Ir ◽  
Hexyl Methacrylate

As a type of functional group, azo-derivatives are commonly used to synthesize responsive materials. Cellulose nanocrystals (CNCs), prepared by acid hydrolysis of cotton, were dewatered and reacted with 2-bromoisobuturyl bromide to form a macro-initiator, which grafted 6-[4-(4-methoxyphenyl-azo) phenoxy] hexyl methacrylate (MMAZO) via atom transfer radical polymerization. The successful grafting was supported by Fourier transform infrared spectroscopy (FT-IR) and Solid magnetic resonance carbon spectrum (MAS 13C-NMR). The morphology and surface composition of the poly{6-[4-(4-methoxyphenylazo) phenoxy] hexyl methacrylate} (PMMAZO)-grafted CNCs were confirmed with Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The grafting rate on the macro-initiator of CNCs was over 870%, and the polydispersities of branched polymers were narrow. The crystal structure of CNCs did not change after grafting, as determined by X-ray diffraction (XRD). The polymer PMMAZO improved the thermal stability of cellulose nanocrystals, as shown by thermogravimetry analysis (TGA). Then the PMMAZO-grafted CNCs were mixed with polyurethane and casted to form a composite film. The film showed a significant light and pH response, which may be suitable for visual acid-alkali measurement and reversible optical storage.

Microwave-assisted solvent-free synthesis and spectral and structural characterization of cyclotriphosphazene hexakis(o-tolylamide)

2018 ◽  
Vol 73 (12) ◽  
pp. 999-1003 ◽  
Author(s):  
Mohammad Hakimi ◽  
Homeyra Rezaei ◽  
Keyvan Moeini ◽  
Heidar Raissi ◽  
Vaclav Eigner ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
Aromatic Rings ◽  
X Ray ◽  
Microwave Assisted ◽  
Ft Ir ◽  
Solvent Free Synthesis

AbstractA new cyclotriphosphazene, 2,2,4,4,6,6-hexakis (o-tolylamono)-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinine (MPAP), was prepared using microwave irradiation and identified by elemental analysis, FT-IR, Raman, 31P NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal, in addition to hydrogen bonds, the network is further stabilized by inter- and intramolecular π–π stacking interactions between aromatic rings.

Preparation and Characterization of Cefradine/Montmorillionite Composites

2012 ◽  
Vol 560-561 ◽  
pp. 434-437 ◽  
Author(s):  
Lan Wang ◽  
Wen Ji Guo ◽  
Yan Zhao Zhao
Keyword(s):  
Gastric Fluid ◽  
Simulated Gastric Fluid ◽  
X Ray Diffraction ◽  
Simulated Intestinal Fluid ◽  
Solution Intercalation ◽  
Method Of Solution ◽  
Ft Ir ◽  
In The Beginning ◽  
Ft Ir Spectroscopy

The objective of this paper was to prepare the composite of crefradine/montmorillionite in the method of solution intercalation. The drug load and intercalation rate varied with the drug concentration. X-ray diffraction (XRD), Fourier transformed infrared (FT-IR) Spectroscopy, and thermal analysis (TG-DSC) were applied to characterize composite mentioned above. Together with drug release tests, results indicate cefradine intercalated into montmorillionite.The release profiles of cefradine/MMT in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.4) at 37°Cduring 10h are shown in Fig. 4. The amount of cefradine in the beginning 2h came up to 35% and 50%, and in the following time, cefradine released slowly. The release behaviors met the requirements of sustained release.

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