Catalytic Application of H4SiW12O40/TiO2-SiO2 in Synthesis of Acetals and Ketals

2014 ◽  
Vol 692 ◽  
pp. 320-325
Author(s):  
Fang Peng ◽  
Yu Lin Xu ◽  
Shi Yin Xiang ◽  
Shui Jin Yang
Keyword(s):  
Calcination Temperature ◽  
Heteropoly Acid ◽  
Load Ratio ◽  
Acid Catalyst ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Activation Time ◽  
Preparation Conditions ◽  
Catalytic Application

The environmental friendly catalyst, H4SiW12O40/TiO2-SiO2 was prepared by the impregnation method. The synthesis of cyclohexanone glycol ketal was as the probe reaction and investigated the different influences on the catalytic activity of H4SiW12O40/TiO2-SiO2 by the quality of the carrier TiO2-SiO2 ratio, load of heteropoly acid, catalyst preparation conditions of the activation time and the calcination temperature, etc. The results showed the best condition for the preparation of the catalyst is the mass ratio of TiO2 and SiO2 is 1: 5, the load ratio of H4SiW12O40 is 10 %, calcination temperature is 300 oC and the roasting time is 3.0 h. Under the condition of the molar ratio of aldehydes (ketones) and glycol (1,2-propanediol) is 1: 1.6, the mass percent of the catalyst is 1.4 %, and the reaction time of 70 min, the yields of eight kinds acetal (ketal) are 71.6 %~ 90.5 %.

Influence of Adding KH2PO4 on WO3/γ-Al2O3 Solid Acid Catalyst for the Synthesis of Acrylic Acid from Lactic Acid

2014 ◽  
Vol 912-914 ◽  
pp. 178-181
Author(s):  
Chang Yuan Wang ◽  
Gui Ying Liu ◽  
Chang Hai Du
Keyword(s):  
Lactic Acid ◽  
Acrylic Acid ◽  
Calcination Temperature ◽  
Acid Concentration ◽  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Lactic Acid Concentration ◽  
Preparation Conditions ◽  
Acid Reaction

KH2PO4-WO3/γ-Al2O3 solid acid catalyst was prepared by the method of impregnation. According to the lactic acid dehydration production of acrylic acid reaction, some parameters including the load of WO3 on γ-Al2O3, the calcination temperature, the reaction temperature and lactic acid concentration were investigated. The results show that the conversion of lactic acid was 92%, and the selectivity of acrylic acid was 29% under the optimized preparation conditions.

Preparation of H5PMo10V2O40 /SBA-15 Catalyst and Application in Synthesis of Tributyl Citrate

2011 ◽  
Vol 236-238 ◽  
pp. 1019-1022
Author(s):  
Bing Hu ◽  
Chuan Qun Hu ◽  
Long Hui Nie ◽  
Ming Xia Fan
Keyword(s):  
Catalytic Activity ◽  
Structural Stability ◽  
Heteropoly Acid ◽  
Acid Catalyst ◽  
Catalytic Synthesis ◽  
High Catalytic Activity ◽  
Impregnation Method ◽  
Dispersion Characteristics ◽  
Fine Dispersion ◽  
Ft Ir

The heteropoly acid catalyst of H5PMo10V2O40 supported on SBA-15 mesoporous mole-cular sieve was prepared by an impregnation method and characterized by nitrogen physisorption, FT-IR,SEM, and used in catalytic synthesis of tributyl citrate. The results show that the heteropoly acid catalyst has fine dispersion characteristics, structural stability, high catalytic activity and better reusability.

scholarly journals Preparation of fly ash-based flocculant and flocculation performance

2021 ◽  
Vol 2079 (1) ◽  
pp. 012006
Author(s):  
Junxin Zhang ◽  
Xiumei Duan
Keyword(s):  
Fly Ash ◽  
Sodium Carbonate ◽  
Thermal Power ◽  
Liquid Product ◽  
Acid Leaching ◽  
Raw Material ◽  
Molar Ratio ◽  
Activation Time ◽  
Activation Temperature ◽  
Preparation Conditions

Abstract Using fly ash from a thermal power plant in Yingkou City as raw material, The inorganic polymer flocculant polyaluminum ferric chloride (PAFC) was prepared by sodium carbonate impregnation, high temperature roasting activation, and acid leaching. The influence of activation temperature and activation time on the leaching of aluminum and iron was investigated through single factor test and orthogonal test. The PAFC preparation conditions were optimized, and the prepared PAFC flocculant product was applied to kaolin turbidity water. The test results showed that the content of aluminum in fly ash was 7.08%, and the content of iron was 4.95%. The mass ratio of the activator sodium carbonate and fly ash was 10:7, the activation temperature was 800°C, and the activation time was 2h. The leaching rates of aluminum and iron were the highest, 88.31% and 53.66% respectively. The optimal conditions for the preparation of the flocculant were as follows: the molar ratio of aluminum to iron was 5.7:1, and the reaction time was 1.5h. The liquid product obtained under these conditions was yellowish brown, and the solid product obtained after being dried was yellow powder.

Effects of Preparation Conditions on Alkali-Activation Reactivity of Chemosynthetic Al2O3-2SiO2 Powders

2015 ◽  
Vol 1120-1121 ◽  
pp. 123-127
Author(s):  
Dong Huang ◽  
Wan Li Lu ◽  
Jin Ying Pang ◽  
Guo Wei Mo ◽  
Shu Juan Yu ◽  
...  
Keyword(s):  
Calcination Temperature ◽  
Sol Gel ◽  
Magic Angle Spinning ◽  
Molar Ratio ◽  
Alkali Activation ◽  
Magic Angle ◽  
Drying Time ◽  
Preparation Conditions ◽  
Key Factor ◽  
Synthetic Temperature

Pure Al2O3-2SiO2 powders with alkali-activation reactivity were prepared by a sol-gel method. The effects of preparation conditions on alkali-activation reactivity were studied and the optimum preparation conditions were obtained. The results show that calcination temperature is a key factor affecting the alkali-activation reactivity of the powders, while other preparation conditions such as synthetic temperature, the molar ratio of solvents to starting materials and drying time have fewer effects on alkali-activation reactivity than calcination temperature. The structure of the powders was investigated by 27Al magic-angle spinning nuclear magnetic resonance spectra. The data show that the Al2O3-2SiO2 powders with the high alkali-activation reactivity are of high content of 5-coordinated Al and the peaks attributed to 5-coordinated Al are strengthened with the rise of calcination temperature of the powders.

The Research on Preparation and Application of a Silicon-Based Efficient Coagulant

2011 ◽  
Vol 295-297 ◽  
pp. 543-546
Author(s):  
Jiao Jiao Wang ◽  
Chun Ying Han ◽  
Li Dan Zhang
Keyword(s):  
Industrial Wastewater ◽  
Experimental Results ◽  
Good Stability ◽  
Molar Ratio ◽  
Good Effect ◽  
Activation Time ◽  
Preparation Conditions ◽  
Silicon Based

In this paper, research was focused on the synthesis of a new efficient coagulant, boron -containing poly-silicate zinc (PSZB).The effect of the SiO2 concentration, Zn/Si molar ratio, B/Si molar ratio, activation time on flocculation properties were examined in detail. And the optimal preparation conditions were determined. At the same time, the industrial wastewater and life wastewater were treated for the properties test. The experimental results showed that the flocculant had good stability and good effect. It is a kind of good performance of flocculants.

Low-Temperature Catalytic Combustion of VOCs over MnOx–ZnO Mixed Oxides Supported on Cordierite Ceramic

2014 ◽  
Vol 989-994 ◽  
pp. 671-675
Author(s):  
Qiong Huang ◽  
Ying Wen Chen ◽  
Shu Bao Shen ◽  
Min Dong Chen
Keyword(s):  
Low Temperature ◽  
High Activity ◽  
Calcination Temperature ◽  
Catalytic Combustion ◽  
Mixed Oxides ◽  
Molar Ratio ◽  
Complete Combustion ◽  
Preparation Conditions ◽  
Cordierite Ceramic ◽  
And Performance

Catalytic combustion of VOCs was investigated over Mn–Zn mixed oxides supported on cordierite ceramic (Cord) and over the promoted Mn-Zn oxides with γ–Al2O3 coating. The properties and performance were characterized by using the XRD, SEM, BET, and TPD techniques. Mn-Zn oxides catalysts with different kinds of γ–Al2O3 sol coating were found to possess a high activity, and the Mn–Zn/γ–Al2O3/Cord (Mn/Zn=2) was identified as the most active that the temperature of complete combustion of toluene was 250°C. Effects of variation of preparation conditions, including molar ratio of Mn and Zn, loading, calcination temperature and different kinds of γ–Al2O3 dipping were investigated.

The Effects of Different Preparation Conditions of IR Catalyst on the Simultaneous Removal of Soot and NOx in the Presence of Rich Oxygen and H2O as Well as SO2

2012 ◽  
Vol 428 ◽  
pp. 61-64 ◽  
Author(s):  
Ting Kun Gu ◽  
Rong Shu Zhu ◽  
Feng Ouyang
Keyword(s):  
Catalytic Activity ◽  
Calcination Temperature ◽  
Supported Catalysts ◽  
Catalytic Performance ◽  
Simultaneous Removal ◽  
Impregnation Method ◽  
Support Material ◽  
Calcination Time ◽  
Preparation Conditions ◽  
Calcination Atmosphere

A series of Ir-supported catalysts were prepared by incipient impregnation method. The activity of Ir catalyst for the simultaneous removal of soot and NOx in the presence of rich-oxygen and H2O as well as SO2 has been studied, and the effects of calcination temperature, calcination time, calcination atmosphere, loading, carrier and precursor on its catalytic performance has also been investigated. Ir catalyst exhibits a high activity. With the calcination temperature increasing, Ir catalytic activity increases firstly and then decreases, and the optimal calcination temperature is 900°C. With the calcination time prolonged, Ir catalytic activity also increases firstly and then decreases, and the optimal calcination time is 3h. The optimal calcination atmosphere is 1.5vol.% H2/N2. Support material and precursor have a little effect on the catalytic activity, and the order is Ir/TiO2 > Ir/ZrO2 > Ir/SiO2 > Ir/Al2O3 > Ir/ZSM-5 and IrCl (CO)[P(C6H5)3]2/ZrO2 > H2IrCl6·6H2O/ZrO2 > IrCl4·4H2O/ZrO2.

scholarly journals Interesterification for biofuel synthesis over HJ-2# caly-supported SO42-/ZrO2 solid acid catalyst

2021 ◽  
Vol 290 ◽  
pp. 01033
Author(s):  
Dong Lixin ◽  
Zhang Xueqiong ◽  
Chen Jing ◽  
Hao Yinan ◽  
Pang Liwen ◽  
...  
Keyword(s):  
Soybean Oil ◽  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Maximum Yield ◽  
Acid Catalyst ◽  
Acid Sites ◽  
Preparation Condition ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Ft Ir

This study makes use of soybean oil to produce biodiesel using SO42-/ZrO2-HJ-2# caly solid acid catalyst (SZ-HJ-2#). It was through coprecipitation and impregnation method that the catalyst was prepared which was then characterized by means of FE-SEM, XRD, EDS, BET, FT-IR, ICP-MS, NH3-TPD and XPS. The catalytic property of the synthesized catalyst was determined by using it to produce biodiesel from soybean oil. A study was carried out to find the effect of the different preparation condition of catalyst affecting the process. For SZ-HJ-2#, Optimized condition of 0.5 mol/L(zirconium salt solution), 1.5 mol/L (the concentration of sulfuric acid impregnating solution) and 450℃(calcination temperature). Optimized conditions of 8.32:1 methanol to soybean oil molar ratio and catalytic loading of 1 wt% at 55℃ with a stirring rate of 500 rpm for a reaction duration of 10 h gave a maximum yield of 89.6 wt%. Moreover, the further investigation indicated the catalytic activities were closely related to the ratio of Brönsted acid sites and intensity on catalysts. Besides, the excellent performance of the catalyst during recycling was shown by conducting reusability study.

scholarly journals ADSORPTION OF CATIONIC DYE FROM AQUEOUS SOLUTION USING COMPOSITE CHICKEN EGGSHELL - ANTHILL CLAY: OPTIMIZATION OF ADSORBENT PREPARATION CONDITIONS

2019 ◽  
Vol 59 (2) ◽  
pp. 192-202 ◽  
Author(s):  
Adeyinka Sikiru Yusuff
Keyword(s):  
Aqueous Solution ◽  
Calcination Temperature ◽  
Quadratic Model ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Cationic Dye ◽  
Mixing Ratio ◽  
Calcination Time ◽  
Adsorption Sites ◽  
Preparation Conditions

A composite adsorbent was prepared from anthill and eggshell mixture, using an incipient wetness impregnation method and it was used for an adsorption of cationic dye (methylene blue, MB) from an aqueous solution. The effects of three preparation parameters including calcination temperature, calcination time and mixing ratio of eggshell to anthill on the MB uptake were investigated using the central composite design (CCD) of response surface methodology (RSM). A quadratic model was developed to predict the response with a high accuracy. The optimal adsorbent sample was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray fluorescence (XRF) spectroscopy. The obtained results revealed that the calcination temperature significantly affected the MB adsorption. The optimum MB uptake of 23.87 mg/g was achieved under the optimum conditions including a calcination temperature of 823.45 °C, calcination time of 3.54 h and eggshell/anthill mixing ratio of 1.89:1. A detailed characterization of an optimal adsorbent sample confirmed the presence of pores, active functional groups and various molecular adsorption sites on its surface. Equilibrium adsorption isotherms and kinetics were also studied and it was revealed that the isotherms and kinetics data fitted well to the Freundlich model and pseudo-second-order kinetics model, respectively.

scholarly journals Effects of Composition and Calcination Temperature on Photocatalytic Evolution over from Glycerol and Water Mixture

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Cancan Fan ◽  
Xitao Wang ◽  
Huanxin Sang ◽  
Fen Wang
Keyword(s):  
Solid Solution ◽  
Hydrogen Production ◽  
Calcination Temperature ◽  
Uv Light ◽  
Light Irradiation ◽  
Molar Ratio ◽  
Glycerol Solution ◽  
Water Mixture ◽  
Impregnation Method ◽  
Catalyst Composition

A series of sulfide coupled semiconductors supported on SiO2, (), was prepared by incipient wet impregnation method. The photocatalysts were characterized by XRD, XPS, TPR, and UV/Vis DRS. Characterization results show that the chemical actions between ZnS and CdS resulted in the formation of solid solutions on the surface of the support and the formation of them is affected by the molar ratio of ZnS/CdS and calcination temperature. Performance of photocatalysts was tested in the home made reactor under both UV light and solar-simulated light irradiation by detecting the rate of the photocatalytic H2evolution from glycerol solution. The hydrogen production rates are related to the catalyst composition, surface structure, photoabsorption property, as well as the amount of solid solution. The maximum rate of hydrogen production, 550 μmol·h−1under UV light irradiation and 210 μmol·h−1under solar-simulated light irradiation, was obtained over Cd0.8Zn0.2S/SiO2solid solution calcined at 723 K.

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