scholarly journals PREPARATION, CHARACTERIZATION, AND CATALYTIC ACTIVITY TEST OF Ni-Mo/NATURAL ZEOLITE ON PYRIDINE HYDRODENITROGENATION

2010 ◽  
Vol 10 (3) ◽  
pp. 327-333 ◽  
Author(s):  
Sri Kadarwati ◽  
Sri Wahyuni ◽  
Wega Trisunaryanti ◽  
Triyono Triyono
Keyword(s):  
Catalytic Activity ◽  
Flow Rate ◽  
Natural Zeolite ◽  
Diffraction Method ◽  
Nitrate Hexahydrate ◽  
Impregnation Method ◽  
Hydrogen Flow Rate ◽  
Hydrogen Flow ◽  
Activity Test ◽  
Catalytic Activity Test

Preparation, characterization, and catalytic activity test of Ni-Mo/natural zeolite on pyridine hydrodenitrogenation were carried out. Preparation of catalyst was conducted by impregnation method using nickel nitrate hexahydrate and ammonium heptamolibdate precursor as Ni and Mo source respectively. Characterization of catalyst was conducted by using gravimetry, atomic absorption spectrophotometry, and X-ray diffraction method. Catalytic activity test on pyridine hydrodenitrogenation was carried out by using flow system reactor with hydrogen flow rate variable. The research results showed that the catalyst's total acidity and crystallinity are increased with level of impregnation success of 96.71% and 90.08% respectively. Ni-Mo/natural zeolites able to increase the catalytic conversion up to 71.78% at 350 °C and hydrogen flow rate of 10 mL/min with more highly varied product distribution. Assuming that the pyridine hydrodenitrogenation follows the pseudo first order kinetics.

scholarly journals Kinetics and Mechanism of Ni/Zeolite-Catalyzed Hydrocracking of Palm Oil into Bio-Fuel

2013 ◽  
Vol 13 (1) ◽  
pp. 77-85 ◽  
Author(s):  
Sri Kadarwati ◽  
Fitri Rahmawati ◽  
Puji Eka Rahayu ◽  
Kasmadi Imam Supardi
Keyword(s):  
Flow Rate ◽  
Palm Oil ◽  
Fixed Bed ◽  
Considerable Effect ◽  
Fixed Bed Reactor ◽  
Nitrate Hexahydrate ◽  
Impregnation Method ◽  
Hydrogen Flow Rate ◽  
Hydrogen Flow ◽  
Cracking Reaction

Kinetics and mechanisms of Ni/zeolite-catalyzed cracking reaction of methyl ester palm oil (MEPO) were studied using a continuous flow-fixed bed reactor system at an atmospheric pressure. The catalyst was prepared by wet impregnation method with a solution of nickel nitrate hexahydrate as the precursor and zeolite as carrier. The characteristics of catalyst including active Ni metal content, crystallinity, total acidity, and porosity were evaluated. The reactions were performed with a varied hydrogen flow rate as a carrier gas as well as a reductant and reaction time. Liquid products were analyzed by GC. Analysis by GC-MS was only conducted on a product at hydrogen flow rate with the best conversion. It has been shown that the catalyst has a superior character for hydrocracking reactions of MEPO into green fuel. No considerable effect of hydrogen flow rate on the total conversion was observed. The tests showed that the kinetics of Ni/zeolite-catalyzed cracking reaction followed pseudo-first order kinetics. GC-MS analysis revealed the formation of light hydrocarbon products with C6-C8 of aliphatic and cyclic components without oxygenates. Distribution of the product indicated that the cracking reaction as well as the isomerization of the products of hydrocracking occurred. Thus, Ni/zeolite-catalyzed cracking involved cracking /hydrogenation, isomerization, cyclization, and deoxygenation.

Amorphous-to-nanocrystalline transition in silicon thin films by hydrogen diluted silane using PE-CVD method

2020 ◽  
Vol 13 ◽  
Author(s):  
Ashok Jadhavar ◽  
Vidya Doiphode ◽  
Ajinkya Bhorde ◽  
Yogesh Hase ◽  
Pratibha Shinde ◽  
...  
Keyword(s):  
Flow Rate ◽  
Volume Fraction ◽  
Defect Density ◽  
Hydrogen Flow Rate ◽  
Spectroscopy Analysis ◽  
Deposition Parameter ◽  
Hydrogen Flow ◽  
Cvd Method ◽  
Silicon Thin Films ◽  
Increasing Trend

: Herein, we report effect of variation of hydrogen flow rate on properties of Si:H films synthesized using PE-CVD method. Raman spectroscopy analysis show increase in crystalline volume fraction and crystallite size implying that hydrogen flow in PECVD promote the growth of crystallinity in nc-Si:H films with an expense of reduction in deposition rate. FTIR spectroscopy analysis indicates that hydrogen content in the film increases with increase in hydrogen flow rate and hydrogen is predominantly incorporated in Si-H2 and (Si-H2)n bonding configuration. The optical band gap determined using E04 method and Tauc method (ETauc) show increasing trend with increase in hydrogen flow rate and E04 is found higher than ETauc over the entire range of hydrogen flow rate studied. We also found that the defect density and Urbach energy also increases with increase in hydrogen flow rate. Photosensitivity (Photo /Dark) decreases from  103 to  1 when hydrogen flow rate increased from 30 sccm to 100 sccm and can attributed to amorphous-to-nanocrystallization transition in Si:H films. The results obtained from the present study demonstrated that hydrogen flow rate is an important deposition parameter in PE-CVD to synthesize nc-Si:H films.

scholarly journals Sliding Mode Control for Stabilizing of Boost Converter in a Solid Oxide Fuel Cell

2013 ◽  
Vol 13 (4) ◽  
pp. 139-147 ◽  
Author(s):  
Junsheng Jiao
Keyword(s):  
Fuel Cell ◽  
Sliding Mode Control ◽  
Flow Rate ◽  
Output Voltage ◽  
Sliding Mode ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Hydrogen Flow Rate ◽  
Dc Voltage ◽  
Hydrogen Flow

Abstract The output voltage of Solid Oxide Fuel Cell (SOFC) is usually changed with the temperature and hydrogen flow rate. Since the fuel cell can generate a wide range of voltages and currents at the terminals, as a consequence, a constant DC voltage and function cannot be maintained by itself as a DC voltage power supply source. To solve this problem, a simple SOFC electrochemical model is introduced to control the output voltage. The Sliding Mode Control (SMC) is used to control the output voltage of the DC-DC converter for maintaining the constant DC voltage when the temperature and hydrogen flow rate are changed. By the simulation results it can be seen that the SMC technique has improved the transient response and reduced the steady state error of DC voltage.

scholarly journals CATALYTIC ACTIVITY TEST OF NiMo AND MoNi IMPREGNATED ON MESOPOROUS CARBON FROM BOVINE BONE GELATIN FOR HYDROCRACKING OF LUBRICANT WASTE

2018 ◽  
Vol 11 (4) ◽  
pp. 1433-1440 ◽  
Author(s):  
Farin Windy Artanti ◽  
Wega Trisunaryanti ◽  
Marthinus Pongsendana ◽  
Triyono ◽  
Iip Izul Falah ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Mesoporous Carbon ◽  
Bovine Bone ◽  
Activity Test ◽  
Catalytic Activity Test

Disilane addition versus silane-hydrogen flow rate effect on the PECVD of silicon thin films

2016 ◽  
Vol 34 (6) ◽  
pp. 061307
Author(s):  
Panagiotis Dimitrakellis ◽  
Eleftherios Amanatides ◽  
Dimitrios Mataras ◽  
Angelos G. Kalampounias ◽  
Nikolaos Spiliopoulos ◽  
...  
Keyword(s):  
Thin Films ◽  
Flow Rate ◽  
Rate Effect ◽  
Hydrogen Flow Rate ◽  
Hydrogen Flow ◽  
Silicon Thin Films ◽  
Flow Rate Effect

The Influence of Deposition Conditions on the Properties of a-Sic:H Thin Films

1990 ◽  
Vol 192 ◽  
Author(s):  
L. Magafas ◽  
D. Girginoudi ◽  
N. Georgoulas ◽  
A. Thanailakis
Keyword(s):  
Thin Films ◽  
Chemical Composition ◽  
Optical Absorption ◽  
Flow Rate ◽  
Growth Conditions ◽  
Optical Absorption Coefficient ◽  
Hydrogen Flow Rate ◽  
Hydrogen Flow ◽  
Composition Structure ◽  
Deposition Conditions

ABSTRACTThe dependence of chemical composition, structure and optoelectronic properties of sputtered a-SiC:H thin films on substrate temperature, Ts, and hydrogen flow rate has been studied. The films are amorphous for the growth conditions used in this work. The chemical composition of the alloys is very little influenced by the Ts, whereas the hydrogen content and the optical absorption coefficient depends strongly on Ts and hydrogen flow rate.

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