Thermodynamic Analysis of Indirect Ethanol Synthesis from Syngas

2012 ◽  
Vol 433-440 ◽  
pp. 457-462
Author(s):  
Ling Jun Zhu ◽  
Shu Rong Wang ◽  
Xin Bao Li ◽  
Qian Qian Yin ◽  
Zhong Yang Luo
Keyword(s):  
Reaction Temperature ◽  
Low Temperatures ◽  
Molar Ratio ◽  
High Alcohol ◽  
Reaction Pressure ◽  
Dimethyl Oxalate ◽  
Temperature And Pressure ◽  
Feed Molar Ratio ◽  
Alcohol Formation ◽  
Ethanol Synthesis

The dependence of chemical equilibrium constant on the reaction temperature and pressure and the feed molar ratio were theoretically calculated for indirect ethanol synthesis from syngas through the coupling of CO with methyl nitrite (MN) to dimethyl oxalate (DMO) and the hydrogenation of DMO to ethanol. It shows that the coupling process and the hydrogenation of DMO to ethanol are highly favorable at all temperatures and pressures, especially at low temperature. The hydrogenation of DMO to ethylene glycol (EG) and the further reaction of ethanol with H2 to high alcohol are thermodynamically favorable at low temperatures, below 630 and 450 K, respectively. Additionally, high reaction pressure is facilitated to EG and high alcohol formation. Accordingly, moderate reaction temperature (up 538 K) and low reaction pressure (below 1 MPa) are beneficial to ethanol production.

Preparation of Alkyl Polyglucoside Surfactants by One-Step

2012 ◽  
Vol 550-553 ◽  
pp. 75-79 ◽  
Author(s):  
Jia Yin Li ◽  
Yan Jun Liu ◽  
Guo Zheng ◽  
Yu Sun ◽  
Ya Ning Hao ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Reaction Conditions ◽  
Reaction Pressure ◽  
Toluenesulfonic Acid ◽  
Catalyst Type ◽  
One Step ◽  
Temperature And Pressure ◽  
Alkyl Polyglucoside

Dodecyl polyglucoside was synthesized by glucose and dodecanol using P-toluenesulfonic acid as catalyst. The effects catalyst type, proportion of material, reaction temperature and pressure were discussed in this paper. The most appropriate reaction conditions: mole ratio of laurel alcohol and glucose 6:1, mass of ratio of P-toluenesulfonic and glucose 0.008:1, reaction temperature 120°C and reaction pressure 5.0kPa.

Simulation and Experimental Study on Methanol Recovery in Continuous Production of Biodiesel via Supercritical Transesterification

2012 ◽  
Vol 550-553 ◽  
pp. 452-457
Author(s):  
Wen Chen ◽  
Ya Li Jin ◽  
Shao Wen Liu ◽  
Zhou Hua Zeng
Keyword(s):  
Gas Phase ◽  
Reaction Temperature ◽  
Continuous Production ◽  
Tubular Reactor ◽  
Molar Ratio ◽  
Supercritical Methanol ◽  
Flash Evaporation ◽  
Reaction Pressure ◽  
One Stage ◽  
Operation Cost

Recycling excessive methanol is simulated and experimentalized by adiabatic flash evaporation. The simulated results show that: methanol recovery and methanol purity in gas phase for one-stage flash process are almost same with two-stage flash process and one-stage flash process is more beneficial by thinking of equipment and operation cost. The experimental results show that flash pressure has a significant influence on methanol recovery and methanol purity in gas phase which can be effectively improved when flashing pressure is reduced. Meanwhile, reaction temperature and reaction pressure also have important effects on methanol recovery and methanol purity in gas phase. For continuous producing biodiesel in supercritical methanol, when the reaction temperature, the reaction pressure and the molar ratio of methanol/oil are kept at 300°C, 15 MPa and 25:1, respectively, methanol recovery and methanol purity in gas phase can reach 90% and 98.8% respectively if the flashing pressure is kept at 0.2MPa. Therefore, the flash evaporation device coupled with tubular reactor for high purity separation of methanol is very effective which can realize comprehensive utilization of heat energy and separation and recycle of methanol.

scholarly journals The Catalytic Oxidation of Formaldehyde by FeOx-MnO2-CeO2 Catalyst: Effect of Iron Modification

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 555
Author(s):  
Yaxin Dong ◽  
Chenguang Su ◽  
Kai Liu ◽  
Haomeng Wang ◽  
Zheng Zheng ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Oxygen Vacancies ◽  
Catalytic Performance ◽  
Active Oxygen ◽  
Molar Ratio ◽  
N2 Adsorption ◽  
Structure Activity ◽  
Iron Modification ◽  
Surface Active ◽  
Catalyst Effect

A series of FeOx-MnO2-CeO2 catalysts were synthesized by the surfactant-templated coprecipitation method and applied for HCHO removal. The influence of Fe/Mn/Ce molar ratio on the catalytic performance was investigated, and the FeOx-MnO2-CeO2 catalyst exhibited excellent catalytic activity, with complete HCHO conversion at low temperatures (40 °C) when the molar ratio of Fe/Mn/Ce was 2/5/5. The catalysts were characterized by N2 adsorption and desorption, XRD, H2-TPR, O2-TPD and XPS techniques to illustrate their structure–activity relationships. The result revealed that the introduction of FeOx into MnO2-CeO2 formed a strong interaction between FeOx-MnO2-CeO2, which facilitated the improved dispersion of MnO2-CeO2, subsequently increasing the surface area and aiding pore development. This promotion effect of Fe enhanced the reducibility and produced abundant surface-active oxygen. In addition, a great number of Oα is beneficial to the intermediate decomposition, whereas the existence of Ce3+ favors the formation of oxygen vacancies on the surface of the catalyst, all of which contributed to HCHO oxidation at low temperatures.

scholarly journals Biogas Dry Reforming for Hydrogen through Membrane Reactor Utilizing Negative Pressure

Fuels ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 194-209
Author(s):  
Akira Nishimura ◽  
Tomohiro Takada ◽  
Satoshi Ohata ◽  
Mohan Lal Kolhe
Keyword(s):  
Energy Source ◽  
Reaction Temperature ◽  
Negative Pressure ◽  
Membrane Reactor ◽  
Reaction Chamber ◽  
Dry Reforming ◽  
Molar Ratio ◽  
Effect Of Pressure ◽  
The Impact

Biogas, consisting of CH4 and CO2, is a promising energy source and can be converted into H2 by a dry reforming reaction. In this study, a membrane reactor is adopted to promote the performance of biogas dry reforming. The aim of this study is to investigate the effect of pressure of sweep gas on a biogas dry reforming to get H2. The effect of molar ratio of supplied CH4:CO2 and reaction temperature is also investigated. It is observed that the impact of psweep on concentrations of CH4 and CO2 is small irrespective of reaction temperature. The concentrations of H2 and CO increase with an increase in reaction temperature t. The concentration of H2, at the outlet of the reaction chamber, reduces with a decrease in psweep. It is due to an increase in H2 extraction from the reaction chamber to the sweep chamber. The highest concentration of H2 is obtained in the case of the molar ratio of CH4:CO2 = 1:1. The concentration of CO is the highest in the case of the molar ratio of CH4:CO2 = 1.5:1. The highest sweep effect is obtained at reaction temperature of 500 °C and psweep of 0.045 MPa.

scholarly journals Rapid and Efficient Synthesis ofω-Alkylenediphosphoric Acids from Phosphorus Oxychloride

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Dalila Meziane ◽  
Abdelhamid Elias ◽  
Erwann Guénin
Keyword(s):  
Microwave Irradiation ◽  
Reaction Temperature ◽  
Phosphorus Oxychloride ◽  
Molar Ratio ◽  
Efficient Synthesis ◽  
Selective Method

The aim of this investigation was to develop an efficient, rapid, and selective method for the synthesis ofω-alkylenediphosphoric acids (HO)2(O)P-O-CH2n-O-P(O)(OH)2from reaction of several diols with phosphorus oxychloride. The reaction was investigated using three methodologies: (i) presence of a base, (ii) classical heating, and (iii) use of microwave irradiation. Influence of reaction temperature and molar ratio of reagents, as well as the nature of the solvent, was studied using these three different methods.

Hydrothermal synthesis of heteroepitaxial Pb(ZrxTi1−x)O3 thin films at 90–150 °C

1997 ◽  
Vol 12 (5) ◽  
pp. 1176-1178 ◽  
Author(s):  
A. T. Chien ◽  
J. S. Speck ◽  
F. F. Lange
Keyword(s):  
Thin Films ◽  
Low Temperatures ◽  
High Dielectric Constant ◽  
Ambient Pressure ◽  
Random Access ◽  
Random Access Memory ◽  
Molar Ratio ◽  
Access Memory ◽  
Eds Analysis ◽  
High Dielectric

Pb(ZrxTi1−x)O3 and PbZrO3 heteroepitaxial thin films were produced in an aqueous solution (10 M KOH) at ambient pressure and low temperatures (90–150 °C) on (001) SrTiO3 and LaAlO3 single crystal substrates. Growth of the Pb(ZrxTi1−x)O3 and PbZrO3 thin films initiates by the formation of {100} faceted islands. Energy dispersive spectroscopy (EDS) analysis of the Pb(ZrxTi1−x)O3 thin film shows that the Zr: Ti ratio is 45: 56, nearly identical to the molar ratio of the precursors. This route might provide a viable low temperature alternative for the formation of high dielectric constant thin films for applications such as dynamic random access memory (DRAM).

Hydrothermal Sintering under Mild Temperature Conditions: Preparation of Calcium-deficient Hydroxyapatite Compacts

2010 ◽  
Vol 65 (8) ◽  
pp. 1038-1044 ◽  
Author(s):  
Kazumichi Yanagisawa ◽  
Jae-Hyen Kim ◽  
Chisato Sakata ◽  
Ayumu Onda ◽  
Eri Sasabe ◽  
...  
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Hot Pressing ◽  
Reaction Parameter ◽  
High Bulk Density ◽  
Temperature And Pressure ◽  
Mild Temperature ◽  
Short Time ◽  
High Bulk ◽  
Dissolution And Precipitation

Calcium-deficient hydroxyapatite (CDHA) prepared by the coprecipitation method was solidified by the hydrothermal hot-pressing technique, and compacts of CDHA with high bulk density beyond 80% were obtained at 200 ℃. Each reaction parameter, viz. reaction temperature, pressure, and time, was systematically changed from the standard conditions to investigate its effects on density, Vickers hardness, and Ca/P ratio of the compacts obtained. The reaction temperature and pressure had a large effect on densification, but not the reaction time because the densification proceeds in a short time. The densification by hydrothermal hot-pressing involved dissolution and precipitation of the starting CDHA powder, so that the Ca/P ratio changed from 1.52 of the starting powders to 1.61 of the compact obtained by hydrothermal hot-pressing at 200 ℃ and 35 MPa for 24 h with the addition of 10 wt.-% water

Synthesis of AM-co-NVP and Thermal Stability in Hostile Saline Solution

2012 ◽  
Vol 602-604 ◽  
pp. 1349-1354 ◽  
Author(s):  
Rui Liu ◽  
Wan Fen Pu ◽  
Qin Peng ◽  
Feng Sheng Yao
Keyword(s):  
Thermal Stability ◽  
Saline Solution ◽  
Heat Stability ◽  
Structure Characterization ◽  
Vinyl Pyrrolidone ◽  
Molar Ratio ◽  
Mass Ratio ◽  
Excellent Thermal Stability ◽  
Hydrolyzed Polyacrylamide ◽  
Feed Molar Ratio

copolymer preparation; structure characterization; thermal stability; brines solution. Abstract. The copolymer (AM-co-NVP) of acrylamide (AM) and vinyl pyrrolidone (NVP) was carried out in the presence of 2,2'-azobis[2-methylpropionamidine] dihydrochloride（V50）as initiator by free radical polymerization. The copolymer was characterized by its chemical structure with Fourier transform infrared spectroscopy (FTIR). The heat resistance of AM-co-NVP at 100°C and 120°C in harsh saline solution with high mineralized concentration ranging from 5×104 mg/L to 20×104 mg/L containing 2.5% (mass ratio) CaCl2, 2.5% (mass ratio) MgCl2 and 95% NaCl (mass ratio) was investigated. The experimental results indicate that AM-co-NVP has excellent thermal stability in saline solution compared to partially hydrolyzed polyacrylamide (HPAM). What is more, the copolymer exhibited the most perfect thermal tolerance in high divalent saline solution when the feed molar ratio of AM and NVP is 91.5 to 8.5. The microstructures of the copolymer samples after thermal aging in hostile environment captured by scanning electron microscope (SEM）further proved the NVP monomer was effectively introduced leading to the copolymer favorable heat stability in particularly high mineralized solution.

Influence Factors of Denitration Study on Catalyst Mn-Ce/TiO2

2013 ◽  
Vol 634-638 ◽  
pp. 526-530
Author(s):  
Chun Xiang Geng ◽  
Qian Qian Chai ◽  
Wei Yao ◽  
Chen Long Wang
Keyword(s):  
Reaction Temperature ◽  
Catalytic Reduction ◽  
Removal Rate ◽  
Load Capacity ◽  
Fixed Bed ◽  
Influence Factors ◽  
Space Velocity ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Ammonia Gas

Selective Catalytic Reduction (SCR) processes have been one of the most widely used denitration methods at present and the property of low tempreture catalyst becomes a hot research. The Mn-Ce/TiO2 catalyst was prepared by incipient impregnation method. The influence of load capacity, reaction temperature, O2 content, etc. on denitration were studied by a fixed bed catalyst reactor with ammonia gas. Results showed that catalyst with load capacity 18% performed high NO removal rate of 90% at conditions of reaction temperature 160°C, low space velocity, NH3/NO molar ratio 1: 1, O2 concentration 6%.

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