scholarly journals Effective Dehydration of Fructose Over Stable Ti-Doped SBA-15 Catalysts

2022 ◽  
Vol 9 ◽  
Author(s):  
Yutong Zhu ◽  
Xiaofei Xu ◽  
Jian He ◽  
Jie Guo ◽  
Ke Song
Keyword(s):  
Reaction Time ◽  
Catalytic Efficiency ◽  
Catalytic Performance ◽  
Reaction Conditions ◽  
Biomass Valorization ◽  
Catalytic Stability ◽  
Effective Synthesis ◽  
Adsorption Desorption ◽  
Addition Amount ◽  
Mesoporous Structures

High-effective synthesis of 5-hydroxymethylfurfural (HMF) from carbohydrates is an interesting reaction among biomass valorization. The as-synthesized Ti-SBA-15 catalysts with mesoporous structures showed high catalytic efficiency for the conversion of fructose to HMF. Ti-SBA-15 catalysts with different Si/Ti ratios were characterized by characterization techniques such as elemental analysis, XRD, TEM, N2 adsorption–desorption, NH3-TPD, and pyridine-FTIR. The acidity of Ti-SBA-15 catalysts could be tuned by altering addition amount of titanium. The effects of reaction conditions, including reaction time, temperature, and amount of catalyst, on the conversions of fructose and the yields of HMF were also investigated. It is found that Ti-SBA-15 catalysts whose Si/Ti ratio is 120 gave the best yields of HMF, which demonstrated 100% conversion of fructose with a maximum HMF yield of 82% at 140°C after 1 h. In addition, its catalytic performance was retained after 5 recycles in fructose conversion reaction, proving its good catalytic stability.

Study on Catalytic Performance of Supported HPW/C Catalyst for Diethyl Adipate Synthesis

2012 ◽  
Vol 468-471 ◽  
pp. 1371-1374
Author(s):  
Ke Nian Wei ◽  
Bin Zhou ◽  
Jiang Quan Ma ◽  
Yan Wang
Keyword(s):  
Physical Chemistry ◽  
Reaction Time ◽  
Adipic Acid ◽  
Acid Content ◽  
Catalytic Performance ◽  
Impregnation Method ◽  
Reaction Conditions ◽  
Catalyst Amount ◽  
Reaction Performance ◽  
Optimal Reaction

HPW/C catalysts were prepared using impregnation method. The physical chemistry properties of the catalysts were characterized employing XRD and NH3-TPD.The effects of HPW loading, catalyst amount and reaction time on the catalyst performances were investigated. The results more acid content and active center contribute to the reaction performance. Under the optimal reaction conditions of 0.8g 29%(w) HPW/C as the catalyst, n(adipic acid): n(ethanol):n(toluene)=1:6:1,5h,the etherification rate was 97.3%.

Preparation and Characterization of Ti-SBA-15 Mesoporous Materials with Varying Si/Ti Molar Ratios

2012 ◽  
Vol 482-484 ◽  
pp. 985-988
Author(s):  
Qiu Ying Huang ◽  
Wei Liu ◽  
Wen Hao Ye ◽  
Xiu Cheng Zheng
Keyword(s):  
Mesoporous Materials ◽  
Hydrothermal Process ◽  
Catalytic Efficiency ◽  
Mesoporous Structure ◽  
Catalytic Performance ◽  
Reaction Conditions ◽  
Molar Ratios ◽  
Good Catalytic Activity ◽  
Epoxidation Of Cyclohexene

Ti-SBA-15 mesoporous materials with different Si/Ti molar ratios were synthesized via a hydrothermal process and characterized by using various techniques. The effect of Si/Ti molar ratios in the gels on the structure and catalytic efficiency in epoxidation of cyclohexene was discussed in details. The results showed that all the Ti-SBA-15 materials retained SBA-15 mesoporous structure and exhibited good catalytic activity. Furthermore,the sample prepared with Si/Ti =50 exhibited the best catalytic performance under the reaction conditions.

scholarly journals Fe3O4@chitosan-tannic acid bionanocomposite as a novel nanocatalyst for the synthesis of pyranopyrazoles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maryam Kamalzare ◽  
Mohammad Reza Ahghari ◽  
Mohammad Bayat ◽  
Ali Maleki
Keyword(s):  
Reaction Time ◽  
Tannic Acid ◽  
High Performance ◽  
Catalytic Performance ◽  
Natural Material ◽  
Magnetic Nanocatalyst ◽  
Reaction Conditions ◽  
One Pot ◽  
Short Reaction Time ◽  
High Yields

AbstractRecently magnetic nanocatalyst has attracted considerable attention because of its unique properties, including high performance, easy separation from the reaction mixture, and recyclability. In this study, a novel magnetic bionanocomposite was synthesized with chitosan and tannic acid as a natural material. The synthesized bionanocatalyst was characterized by essential analysis. Fe3O4@chitosan-tannic acid as a heterogeneous nanocatalyst was successfully applied to synthesize pyranopyrazole and its derivatives by a one-pot four-component reaction of malononitrile, ethyl acetoacetate, hydrazine hydrate, and various aromatic aldehyde. At the end of the reaction, the nanocatalyst was separated from the reaction mixture and was reused several times with no significant decrease in its catalytic performance. Simple purification of products, the ability for recovering and reusing the nanocatalyst, eco-friendliness, high yields of pure products, mild reaction conditions, short reaction time, non-toxicity, economically affordable are some of the advantages of using the fabricated nanocatalyst in the synthesis of pyranopyrazole.

Synthesis of Methylal from Methanol and Trioxane over Acidic Resin

2011 ◽  
Vol 396-398 ◽  
pp. 929-934 ◽  
Author(s):  
Jing Zhang ◽  
Zhen Chen ◽  
Jun He ◽  
Zhi Rong Zhu
Keyword(s):  
Reaction Time ◽  
Organic Solvent ◽  
Reaction Temperature ◽  
Catalytic Performance ◽  
Reaction Conditions ◽  
Amberlyst 15 ◽  
Β Zeolite ◽  
Acidic Resin

The synthesis of methylal from methanol and trioxane was investigated by using acidic resin as a catalyst, and a variety of solvents were also tested such as toluene, 1,4-dioxane, N,N-dimethylformamide. Comparatively, the organic solvent was suitable for obtaining the better catalytic performance. Among the acidic resin tested, Amberlyst15 showed the highest conversion. Moreover, the reaction conditions were optimized over the modified β zeolite. As a result, the proper reaction conditions are 1,4-dioxane as solvent, reaction temperature 70°C, n(methanol):n(trioxane) =2.2:1, with catalyst 5 wt% and reaction time 3 h. Under the above condition, the yield of methylal may reach about 62 % with Amberlyst 15.

scholarly journals Synthesis and process optimization of Boscalid by catalyst Pd-PEPPSI-IPrDtBu-An

2021 ◽  
pp. 3-3
Author(s):  
Jian Xu ◽  
Xiao-Bing Lan ◽  
Lin-Jian Xia ◽  
Yi Yang ◽  
Gao Cao
Keyword(s):  
Raw Materials ◽  
Condensation Reaction ◽  
Suzuki Reaction ◽  
Coupling Reaction ◽  
Catalytic Efficiency ◽  
Catalytic Performance ◽  
Synthesis Process ◽  
Reaction Conditions ◽  
Cross Coupling Reaction ◽  
Optimal Reaction

The purpose of this research was to reduce the amount of noble metal palladium catalyst and improve the catalytic performance in the Suzuki-Miyaura cross-coupling reaction, which is the key step in the synthesis of Boscalid. Taking o-bromonitrobenzene and p-chlorophenylboronic acid as raw materials, three kinds of Pd-PEPPSI-IPr catalysts were synthesized and employed in the Suzuki reaction, and then the biaryl product was subjected to reduction and condensation reaction to prepare Boscalid. Under optimal reaction conditions, the result showed that the catalytic system exhibits highest catalytic efficiency under aerobic conditions, giving the 2-(4-chlorophenyl)nitrobenzene over 99 % yield. Moreover, the Pd-PEPPSI-IPrDtBu-An catalyst was minimized to 0.01mol%. The synthesis process was mild, the post-treatment was simple, and the production cost was reduced which makes it suitable for industrial production.

scholarly journals Influence of UiO-66(Zr) Preparation Strategies in Its Catalytic Efficiency for Desulfurization Process

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3009 ◽  
Author(s):  
Alexandre M. Viana ◽  
Susana O. Ribeiro ◽  
Baltazar de Castro ◽  
Salete S. Balula ◽  
Luís Cunha-Silva
Keyword(s):  
Reaction Time ◽  
Metal Organic Framework ◽  
Oxidative Desulfurization ◽  
Catalytic Efficiency ◽  
Porous Metal ◽  
Catalytic Performance ◽  
Cooling Time ◽  
High Catalytic Activity ◽  
Desulfurization Process ◽  
Desulfurization Efficiency

Porous metal-organic framework (MOF) materials UiO-66(Zr) obtained by solvothermal and microwave advanced synthesis (MWAS) procedures were characterized, and their catalytic efficiency was investigated for oxidative desulfurization (ODS) processes using a multicomponent model diesel containing benzothiophene and dibenzothiophene derivatives. The preparation parameters as the cooling time after oven use in the solvothermal procedure, and also the reaction time in the MWAS method seemed to play an important role in the catalytic performance of the UiO-66(Zr) material, as well as in its recycle capacity. The material prepared by the solvothermal procedure with a fast cooling time showed the best catalytic performance (desulfurization efficiency of 99.5% after 3 h). However, the application of the UiO-66(Zr) material prepared by the MWAS method (desulfurization efficiency of 96% after 3 h) conciliated a higher number of advantages, such as shorter reaction time preparation (15 min) and high catalytic activity for a higher number of reaction cycles. The UiO-66(Zr) prepared by the MWAS method was used for the first time in an oxidative desulfurization process, and according to the catalytic results obtained (high recycle capacity and stability) and shorter reaction time preparation, seems to be a promising material for industrial application.

CuO nanostructures of variable shapes as an efficient catalyst for [3 + 2] cycloaddition of azides with terminal alkyne

RSC Advances ◽  
2016 ◽  
Vol 6 (104) ◽  
pp. 102733-102743 ◽  
Author(s):  
Anupamjeet Kaur ◽  
Sukhmani Mann ◽  
Bhupesh Goyal ◽  
Bhupender Pal ◽  
Deepti Goyal
Keyword(s):  
Reaction Time ◽  
Cycloaddition Reaction ◽  
Catalytic Efficiency ◽  
Terminal Alkyne ◽  
Reaction Conditions ◽  
Efficient Catalyst ◽  
Short Reaction Time ◽  
Cuo Nanowires

CuO nanowires exhibited highest catalytic efficiency for the cycloaddition reaction between azide and terminal alkyne, featuring short reaction time, soft reaction conditions and complete regioselectivity.

scholarly journals Synthesis of Dimethyl Carbonate from CO2 and Methanol over Zr-Based Catalysts with Different Chemical Environments

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 710
Author(s):  
Linmeng Huo ◽  
Tian Wang ◽  
Keng Xuan ◽  
Lei Li ◽  
Yanfeng Pu ◽  
...  
Keyword(s):  
Dimethyl Carbonate ◽  
Lewis Acid Site ◽  
Catalytic Performance ◽  
Lewis Base ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
X Ray ◽  
Good Catalytic Activity ◽  
Adsorption Desorption

The adsorption and activation of both CO2 and methanol are mainly affected by the distance of the Lewis acid site, Zr4+, and Lewis base, Zr4+/O2−, of the Zr-based catalysts. In this paper, Zr-incorporated SBA-15 (Zr-SBA-15) and Zr-grafted SBA-15 (Zr/SBA-15) catalysts were prepared with different Zr environments, and were analyzed with N2 adsorption–desorption isotherms, X-ray diffraction, UV-vis spectra, and XPS. It was proposed that Zr-SBA-15 catalyst with Si-O-Zr-OH and Zr-O-Si-OH structure exhibited non-adjacent sites between Zr4+ and Zr4+/O2−, while Zr/SBA-15 catalyst with Zr-O-Zr-OH structure showed neighboring sites between Zr4+ and Zr4+/O2−. Furthermore, the Zr/SBA-15 catalyst exhibited good catalytic activity, while no DMC was detected over the Zr-SBA-15 catalyst at the same reaction conditions. For combined in situ infrared and catalytic performance, it was indicated that the methanol and CO2 could be activated to form DMC, only when the Zr4+ and Zr4+/O2− sites existed and were adjacent to each other in the Zr-O-Zr-OH of Zr/SBA-15 catalyst.

Pd/ZrO2: An Efficient Catalyst for Liquid Phase Oxidation of Toluene in Solvent Free Conditions

2017 ◽  
Vol 15 (2) ◽  
Author(s):  
Mohsin Siddique ◽  
Muhammad Saeed ◽  
Mohammad Ilyas ◽  
Hussain Gulab
Keyword(s):  
Batch Reactor ◽  
Catalytic Efficiency ◽  
Catalytic Performance ◽  
Solvent Free ◽  
Catalyst Loading ◽  
Similar Reaction ◽  
Reaction Conditions ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Free Oxidation

Abstract 0.1 % Pd/ZrO2 was synthesized and characterized by various physicochemical techniques and was successfully used as catalyst for solvent free oxidation of toluene in the presence of molecular oxygen using batch reactor. The catalytic performance of Pd/ZrO2 was explored in terms of effect of catalyst loading, reaction time, temperature and partial pressure of oxygen on oxidation of toluene in solvent free conditions. Pd/ZrO2 was found as a stable catalyst under the reaction conditions. Used catalyst exhibited the same catalytic efficiency as fresh catalyst under similar reaction conditions. Reaction was taking place according to Langmuir-Hinshelwood type of mechanism.

scholarly journals Highly Selective pH-Dependent Ozonation of Cyclohexane over Mn/γ-Al2O3 Catalysts at Ambient Reaction Conditions

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 958 ◽  
Author(s):  
Siphumelele Thandokwazi Mkhondwane ◽  
Viswanadha Srirama Rajasekhar Pullabhotla
Keyword(s):  
Electron Microscopy ◽  
Reaction Time ◽  
Catalytic Performance ◽  
Gamma Alumina ◽  
Reaction Conditions ◽  
X Ray ◽  
Ozonation Time ◽  
Ft Ir ◽  
Percentage Conversion ◽  
Ft Ir Spectroscopy

The selective oxidation of cyclohexane to a mixture of cyclohexanol and cyclohexanone (KA oil) is one of the imperative reactions in industrial processes. In this study, the catalytic performance of manganese-supported gamma alumina (Mn/γ-Al2O3) catalysts is investigated in the selective oxidation of cyclohexane at ambient conditions using ozone. The catalysts were prepared by the wet impregnation method, and their physio-chemical properties were studied by Fourier Transform Infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM-EDX), Transmission Electron Microscopy (TEM), Inductively Coupled Plasma (ICP) spectroscopy, and Brunauer Emmett and Teller (BET). The reaction conditions were optimised considering various parameters such as reaction time, pH, and various percentages of the manganese supported in gamma alumina. The oxidation of cyclohexane was conducted in an impinger reactor unit at pH 3, 7, and 11 for 1 h of ozonation time. The aliquots were collected after 30 min and 1 h of ozonation time and analysed with GC-MS and FT-IR spectroscopy. The 2.5% Mn/γ-Al2O3 catalyst exhibited a significantly enhanced catalytic performance at pH 3 and 7 with a percentage conversion of 9% and 15% at pH 3 and 7, respectively, after 30 min of ozonation time. However, after 1 h of ozonation time, the percentage conversions were increased to 23% and 29% at pH 3 and 7, respectively. At pH 11, 5% Mn/γ-Al2O3 exhibit high catalytic performance with a percentage conversion of 19% and 31% after 30 minutes and 1 h of ozonation time, respectively. The percentage selectivity obtained is 100% toward KA oil and/or cyclohexanone depending on pH and reaction time.

Sign in / Sign up

Export Citation Format

Share Document