Preparation and catalytic performance of biomass-based solid acid catalyst from Pennisetum sinense for cellulose hydrolysis

Cogon grass (Imperata cylindrica) is convertible into glucose by hydrolysis process, which usually requires a catalyst. A solid acid catalyst of sulfonated carbon was used in this work. This study aimed to observe the viability of candlenut shell as carbonaceous source in solid acid catalyst production and to characterize the sulfonated carbon. The carbonization was performed at 250-550 ºC for 4 h, while sulfonation was carried out at 100-180 ºC for 6 h. Sulfonated carbon was then characterized by H+ activity/acid density test, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX) and Fourier transform infrared (FTIR) spectroscopy. Sulfonated carbon was then tested as a heterogeneous catalyst for hydrolysis reaction. The reaction was performed in a stainless steel batch reactor at 100 ºC for 6 h. Glucose formed by hydrolysis was measured by dinitrosalicylic acid (DNS) method. Results of this study suggested that sulfonated carbon derived from candlenut shell may be used as a catalyst for cogon grass cellulose hydrolysis to produce glucose

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Synthesis of 2,3-dihydroquinazolin-4(1H)-ones catalyzed by Perchlorated Zirconia (HClO4/ZrO2) nanoparticles as a novel solid acid catalyst

Nanoscience and Nanotechnology ◽

10.18063/nn.v0i0.449 ◽

2018 ◽

Vol 2 (2) ◽

Author(s):

Seyed Yousef Mosavian

Keyword(s):

Solid Acid ◽

Condensation Reaction ◽

Solid Acid Catalyst ◽

Sol Gel ◽

Acid Catalyst ◽

Catalytic Performance ◽

Acid Sites ◽

Zro2 Nanoparticles ◽

Calcination Temperatures ◽

Aldehydes And Ketones

Zirconia was synthesized in nanosize by sol-gel method and perchlorated zirconia (HClO4/ZrO2) with various calcination temperatures were prepared and characterized by XRD, FTIR and SEM techniques. The catalyst acidity characters, including the acidicstrength and the total number of acid sites were determined by potentiometric titration. The catalytic performance experiments show that the HClO4/ZrO2 with calcination temperature of 300 °C has the best catalytic activity. 2,3-Dihydroquinazolin-4(1H)-ones wereprepared in good to excellent yields via condensation reaction of oaminobenzamide and various types of aldehydes and ketones in the presence of HClO4/ZrO2 nanoparticles as an efficient solid acid catalyst. The catalyst is reusable with moderate loss in activity.

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Synthesis, Characterization and Catalytic Performance ofH3SiW12O40/SiO2Prepared by Sol-Gel Technique

Journal of Nanotechnology ◽

10.1155/2011/507692 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

W. N. R. W. Isahak ◽

M. Ismail ◽

N. M. Nordin ◽

J. M. Jahim ◽

M. A. Yarmo

Keyword(s):

Heteropoly Acid ◽

Solid Acid ◽

Solid Acid Catalyst ◽

Sol Gel ◽

Acid Catalyst ◽

Catalytic Performance ◽

Environmentally Benign ◽

Esterification Reaction ◽

Silicotungstic Acid ◽

Gel Technique

The purpose of this work is to study the synthesis, characterization, and catalytic performance of two types of solid heteropoly acid catalysts, namely, silicotungstic acid bulk (STAB) and STA-silica sol-gel (STA-SG) compared with sulfuric acid. From the XPS analyses, there was a significant formation of W-O-Si, W-O-W, and Si-O-Si bonding in STA-SG compared to that in STAB. The main spectra of O1s (90.74%, 531.5 eV) followed by other O1s peak (9.26%, 532.8 eV) were due to the presence of W-O-W and W-O-Si bonds, respectively. The STA-SG catalyst was found to be the more environmentally benign solid acid catalyst for the esterification reaction between oleic acid and glycerol due to its lower toxicity supported by silica via sol-gel technique. In addition, the ease of separation for STA-SG catalyst was attributed to its insoluble state in the product phase. The esterification products were then analysed by FTIR and HPLC. Both the H2SO4and the STAB gave high conversion of 100% and 98% but at a lower selectivity of GME with 81.6% and 89.9%, respectively. On the contrary, the STA-SG enabled a conversion of 94% but with a significantly higher GME selectivity of 95%, rendering it the more efficient solid acid catalyst.

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A New Method for Solid Acid Catalyst Evaluation for Cellulose Hydrolysis

Sustainable Chemistry ◽

10.3390/suschem2040036 ◽

2021 ◽

Vol 2 (4) ◽

pp. 645-669

Author(s):

Maksim Tyufekchiev ◽

Jordan Finzel ◽

Ziyang Zhang ◽

Wenwen Yao ◽

Stephanie Sontgerath ◽

...

Keyword(s):

Solid Acid ◽

Reaction Pathway ◽

Solid Acid Catalyst ◽

False Negative ◽

Acid Catalyst ◽

Cellulose Hydrolysis ◽

Solid Acids ◽

Solid Acid Catalysts ◽

Acid Catalysts ◽

Supernatant Liquid

A systematic and structure-agnostic method for identifying heterogeneous activity of solid acids for catalyzing cellulose hydrolysis is presented. The basis of the method is preparation of a supernatant liquid by exposing the solid acid to reaction conditions and subsequent use of the supernatant liquid as a cellulose hydrolysis catalyst to determine the effects of in situ generated homogeneous acid species. The method was applied to representative solid acid catalysts, including polymer-based, carbonaceous, inorganic, and bifunctional materials. In all cases, supernatant liquids produced from these catalysts exhibited catalytic activity for cellulose hydrolysis. Direct comparison of the activity of the solid acid catalysts and their supernatants could not provide unambiguous detection of heterogeneous catalysis. A reaction pathway kinetic model was used to evaluate potential false-negative interpretation of the supernatant liquid test and to differentiate heterogeneous from homogeneous effects on cellulose hydrolysis. Lastly, differences in the supernatant liquids obtained in the presence and absence of cellulose were evaluated to understand possibility of false-positive interpretation, using structural evidence from the used catalysts to gain a fresh understanding of reactant–catalyst interactions. While many solid acid catalysts have been proposed for cellulose hydrolysis, to our knowledge, this is the first effort to attempt to differentiate the effects of heterogeneous and homogeneous activities. The resulting supernatant liquid method should be used in all future attempts to design and develop solid acids for cellulose hydrolysis.

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Acid Properties of GO and Reduced GO as Determined by Microcalorimetry, FTIR, and Kinetics of Cellulose Hydrolysis-Hydrogenolysis

Catalysts ◽

10.3390/catal10121393 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1393

Author(s):

Van Chuc Nguyen ◽

Sarah Kheireddine ◽

Amar Dandach ◽

Marion Eternot ◽

Thi Thu Ha Vu ◽

...

Keyword(s):

Graphene Oxide ◽

Solid Acid ◽

Solid Acid Catalyst ◽

High Mobility ◽

Acid Catalyst ◽

Strong Acid ◽

Cellulose Hydrolysis ◽

Acid Sites ◽

Pyridine Adsorption ◽

Nh3 Adsorption

Graphene oxide addresses increasing interests as a solid acid catalyst working in water for carbohydrate conversion. If there is a general agreement to correlate its unique catalytic performances to its ability to adsorb sugars, the origin of its acidity remains controversial. In this article, we study the acid strength of graphene oxide (GO) prepared by modified Hummers method and that of reduced GO by calorimetry of NH3 adsorption and by FTIR of pyridine adsorption. Very strong acid sites are detected on GO by calorimetry, while reduced graphene oxide (reGO) is not very acidic. The FTIR of pyridine adsorption shows the prevailing presence of Br∅nsted acid sites and a unique feature, the presence of pyridine coordinated by hydrogen bonds. This exceptionally strong Br∅nsted acidity is tentatively explained by the presence of graphene domains decorated by hydroxyl, carboxylic, or sulfonated groups within the GO sheet, resulting in a high mobility of the negative charges which makes the proton free and explains its strong acidity. Accordingly, only GO is active and selective for native cellulose hydrolysis, leading to 27% yield in glucose. Finally, we show that sugar alcohols cannot be formed directly from cellulose using GO combined with Pt/re-GO under hydrogen, explained by the reduction of oxygenated functions of GO. The instability of the functional groups of GO in a reducing atmosphere is the weak point of this peculiar solid acid.

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Synthesis of Sulfonic Acid-Functionalized Zirconium Poly(Styrene-Phenylvinyl-Phosphonate)-Phosphate for Heterogeneous Epoxidation of Soybean Oil

Catalysts ◽

10.3390/catal9090710 ◽

2019 ◽

Vol 9 (9) ◽

pp. 710 ◽

Cited By ~ 1

Author(s):

Xiaochuan Zou ◽

Xuyuan Nie ◽

Zhiwen Tan ◽

Kaiyun Shi ◽

Cun Wang ◽

...

Keyword(s):

Catalytic Activity ◽

Soybean Oil ◽

Sulfonic Acid ◽

Solid Acid ◽

Solid Acid Catalyst ◽

Acid Catalyst ◽

Thiol Group ◽

Catalytic Performance ◽

X Ray ◽

Sulfonic Acid Groups

In this paper, a solid acid catalyst (ZPS–PVPA–SO3H) was prepared by anchoring thiol group on zirconium poly(styrene-phenylvinyl-phosphonate)-phosphate (ZPS–PVPA), followed by oxidation of thiol groups to obtain sulfonic acid groups. The solid acid catalyst was characterized by XPS, X-ray, EDS, SEM, and TG-DSC. The successful preparation of sulfonic acid-functionalized ZPS–PVPA was confirmed. Subsequently, the catalytic performance of ZPS–PVPA–SO3H was investigated in the epoxidation of soybean oil. The results demonstrated that ZPS–PVPA–SO3H can effectively catalyze epoxidation of soybean oil with TBHP as an oxidant. Moreover, there was no significant decrease in catalytic activity after 5 repeated uses of the ZPS–PVPA–SO3H. Interestingly, the ZPS–PVPA–SO3H was kept in 2 mol/L of HCl overnight after the end of the seventh reaction, and the catalytic activity was gradually restored during the eighth to tenth cycles.

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