scholarly journals Directional Synthesis of Furfural Compounds From Holocellulose Catalyzed by Sulfamic Acid

2021 ◽  
Author(s):  
Yuchan Lu ◽  
Qiao He ◽  
Qiao Peng ◽  
Wenhai Chen ◽  
Guozhi Fan ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Active Sites ◽  
Sulfamic Acid ◽  
Volume Ratio ◽  
Corn Cob ◽  
Catalyst Amount ◽  
Solvent Type ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of ◽  
Direct Hydrolysis

Abstract The coproduction of 5-hydroxymethylfurfural (5-HMF) and furfural (FUR) via the direct hydrolysis of holocellulose analogue composed of cellulose and hemicellulose was investigated. The effects of catalyst amount, solvent type and amount, reaction temperature and time using sulfamic acid with dual active sites as catalyst were also studied. The yields of 5-HMF and FUR at 37.2% and 62.0% were obtained with the volume ratio of γ-valerolactone to water of 25:1 at 180 oC for 3 h. The conversion of corn cob holocellulose and wheat straw holocellulose to furfural compounds was then carried out under the identical conditions. Yields of 5-HMF at 26.6% and 28.5%, and yields of FUR at 34.5% and 26.1% were obtained, respectively. A possible mechanism for the coproduction of 5-HMF and FUR from holocellulose was proposed. It is believed that there is a synergistic effect between the hydrolysis of cellulose and hemicellulose during the conversion of holocellulose.

scholarly journals Conditions of hydrolysis with a specific pair of endo- and exo-cellulases

2021 ◽  
Author(s):  
Yoshiki Kitano
Keyword(s):  
Synergistic Effect ◽  
Crystalline Cellulose ◽  
Carbohydrate Binding ◽  
Amorphous Cellulose ◽  
Potential Synergy ◽  
Hydrolysis Of Cellulose ◽  
Potential Alternative ◽  
Specific Pair ◽  
Hydrolysis Of ◽  
Increased Activity

Enzymatic hydrolysis of cellulose is a technology involved in the production of bioethanol, a potential alternative renewable energy. Many cellulases with endo- and exo- type of activity are known to hydrolyze cellulose synergistically. In this thesis, potential synergy between an endo-cellulase, Cel5B, with and without a carbohydrate- binding module (CBM6), and a new exo-cellulase, CBH1, from Trichoderma harzianum FP108 were examined during the hydrolysis of semi- crystalline cellulose (Avicel). Since CBM6 is recognized as having a high affinity for amorphous cellulose, it was hypothesized that this affinity could enhance the synergistic effect between the endo- and exo-cellulases by focusing the action to Cel5B+CBM6 on the amorphous regions of the Avicel substrate. The increased activity of Cel5B+CBM6 over Cel5B alone was confirmed. However, in contrast to our expectations, a synergistic effect was not observed between either endo- and exo-cellulase pairs. From the obtained hydrolysis yield, it was inferred that Cel5B+CBM6 may have exo-type activity that caused a competitive interaction with the exo-cellulase, which resulted in no synergy.

Effect of solids loading and solvent type on the enzymatic hydrolysis of cellulose

2016 ◽  
Vol 92 (1) ◽  
pp. 224-229 ◽  
Author(s):  
Gary Brodeur ◽  
Elizabeth Yau ◽  
John Collier ◽  
John Telotte ◽  
Subramanian Ramakrishnan
Keyword(s):  
Enzymatic Hydrolysis ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Solids Loading ◽  
Solvent Type ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

scholarly journals Conditions of hydrolysis with a specific pair of endo- and exo-cellulases

2021 ◽  
Author(s):  
Yoshiki Kitano
Keyword(s):  
Synergistic Effect ◽  
Crystalline Cellulose ◽  
Carbohydrate Binding ◽  
Amorphous Cellulose ◽  
Potential Synergy ◽  
Hydrolysis Of Cellulose ◽  
Potential Alternative ◽  
Specific Pair ◽  
Hydrolysis Of ◽  
Increased Activity

Enzymatic hydrolysis of cellulose is a technology involved in the production of bioethanol, a potential alternative renewable energy. Many cellulases with endo- and exo- type of activity are known to hydrolyze cellulose synergistically. In this thesis, potential synergy between an endo-cellulase, Cel5B, with and without a carbohydrate- binding module (CBM6), and a new exo-cellulase, CBH1, from Trichoderma harzianum FP108 were examined during the hydrolysis of semi- crystalline cellulose (Avicel). Since CBM6 is recognized as having a high affinity for amorphous cellulose, it was hypothesized that this affinity could enhance the synergistic effect between the endo- and exo-cellulases by focusing the action to Cel5B+CBM6 on the amorphous regions of the Avicel substrate. The increased activity of Cel5B+CBM6 over Cel5B alone was confirmed. However, in contrast to our expectations, a synergistic effect was not observed between either endo- and exo-cellulase pairs. From the obtained hydrolysis yield, it was inferred that Cel5B+CBM6 may have exo-type activity that caused a competitive interaction with the exo-cellulase, which resulted in no synergy.

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

Immobilized Nanoparticles-Mediated Enzymatic Hydrolysis of Cellulose for Clean Sugar Production: A Novel Approach

2019 ◽  
Vol 15 (3) ◽  
pp. 296-303 ◽  
Author(s):  
Swapnil Gaikwad ◽  
Avinash P. Ingle ◽  
Silvio Silverio da Silva ◽  
Mahendra Rai
Keyword(s):  
Catalytic Activity ◽  
Enzymatic Hydrolysis ◽  
Immobilized Enzyme ◽  
Free Enzyme ◽  
Magnetic Nanomaterials ◽  
Sugar Production ◽  
Cellulase Enzyme ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

Background: Enzymatic hydrolysis of cellulose is an expensive approach due to the high cost of an enzyme involved in the process. The goal of the current study was to apply magnetic nanomaterials as a support for immobilization of enzyme, which helps in the repeated use of immobilized enzyme for hydrolysis to make the process cost-effective. In addition, it will also provide stability to enzyme and increase its catalytic activity. Objective: The main aim of the present study is to immobilize cellulase enzyme on Magnetic Nanoparticles (MNPs) in order to enable the enzyme to be re-used for clean sugar production from cellulose. Methods: MNPs were synthesized using chemical precipitation methods and characterized by different techniques. Further, cellulase enzyme was immobilized on MNPs and efficacy of free and immobilized cellulase for hydrolysis of cellulose was evaluated. Results: Enzymatic hydrolysis of cellulose by immobilized enzyme showed enhanced catalytic activity after 48 hours compared to free enzyme. In first cycle of hydrolysis, immobilized enzyme hydrolyzed the cellulose and produced 19.5 ± 0.15 gm/L of glucose after 48 hours. On the contrary, free enzyme produced only 13.7 ± 0.25 gm/L of glucose in 48 hours. Immobilized enzyme maintained its stability and produced 6.15 ± 0.15 and 3.03 ± 0.25 gm/L of glucose in second and third cycle, respectively after 48 hours. Conclusion: This study will be very useful for sugar production because of enzyme binding efficiency and admirable reusability of immobilized enzyme, which leads to the significant increase in production of sugar from cellulosic materials.

DISTRIBUTION OF HEXOSAMINE IN ELEGTROPHORETIC FRACTIONS OF AVIAN, BOVINE, PORCINE, AND HUMAN SERA

1967 ◽  
Vol 45 (4) ◽  
pp. 541-550 ◽  
Author(s):  
A. P. Gaunce ◽  
P. A. Anastassiadis
Keyword(s):  
Human Blood ◽  
Filter Paper ◽  
Cationic Resin ◽  
Human Sera ◽  
Hydrolysis Of ◽  
Direct Hydrolysis

The distribution of hexosamine among the proteins of avian, bovine, porcine, and human blood sera was studied by electrophoresis on filter paper. Hexosamine was determined after direct hydrolysis of stained sections of the paper, followed by chromatography of hydrolysates on cationic resin. Some substantial and statistically significant differences in hexosamine and protein contents of the zones were found among species.

In Situ Microscopy for In-line Monitoring of the Enzymatic Hydrolysis of Cellulose

2013 ◽  
Vol 85 (17) ◽  
pp. 8121-8126 ◽  
Author(s):  
Britta Opitz ◽  
Andreas Prediger ◽  
Christian Lüder ◽  
Marrit Eckstein ◽  
Lutz Hilterhaus ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

scholarly journals Synergistic Effect of Alkali Na and K Promoter on Fe-Co-Cu-Al Catalysts for CO2 Hydrogenation to Light Hydrocarbons

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 735
Author(s):  
Yuhao Zheng ◽  
Chenghua Xu ◽  
Xia Zhang ◽  
Qiong Wu ◽  
Jie Liu
Keyword(s):  
Synergistic Effect ◽  
Active Sites ◽  
Intermediate Formation ◽  
Active Phase ◽  
Dissociative Adsorption ◽  
Co2 Hydrogenation ◽  
Chain Growth ◽  
Co2 Conversion ◽  
Light Hydrocarbons ◽  
Active Centers

Alkali metal K- and/or Na-promoted FeCoCuAl catalysts were synthesized by precipitation and impregnation, and their physicochemical and catalytic performance for CO2 hydrogenation to light hydrocarbons was also investigated in the present work. The results indicate that Na and/or K introduction leads to the formation of active phase metallic Fe and Fe-Co crystals in the order Na < K < K-Na. The simultaneous introduction of Na and K causes a synergistic effect on increasing the basicity and electron-rich property, promoting the formation of active sites Fe@Cu and Fe-Co@Cu with Cu0 as a crystal core. These effects are advantageous to H2 dissociative adsorption and CO2 activation, giving a high CO2 conversion with hydrogenation. Moreover, electron-rich Fe@Cu (110) and Fe-Co@Cu (200) provide active centers for further H2 dissociative adsorption and O-C-Fe intermediate formation after adsorption of CO produced by RWGS. It is beneficial for carbon chain growth in C2+ hydrocarbons, including olefins and alkanes. FeCoCuAl simultaneously modified by K-Na exhibits the highest CO2 conversion and C2+ selectivity of 52.87 mol% and 89.70 mol%, respectively.

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