scholarly journals PREPARATION OF INORGANIC CATALYST BASED HEMATITE (-Fe2O3) COMPOUND EXTRACTED FROM ACEH IRON ORE MINERAL AND ITS CATALYTIC ACTIVITY ON TRANSESTERIFICATION OF COCONUT OIL

2019 ◽  
Vol 19 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Muliadi Ramli ◽  
Anneza Astriet ◽  
T. Banta Darmawan ◽  
Saiful Saiful ◽  
Susilawati Susilawati ◽  
...  

Hematite (Fe2O3) was successfully extracted from the Aceh iron ore mineral by precipitation method with employing sulphuricacid (H2SO4) as chemical agent.  Furthermore, the extracted hematite was modified with sodium metal (K), namely it doped with NaOH of 5% and 10% (w/w), respectively. Based on the characterization results using XRD and SEM- EDS proved that modified catalyst (Na2O/Fe2O3) with their homogeneous size were resulted while the hematite (Fe2O3) particles was dopped withNaOH at its low concentration of (5% wt/wt), however while doping with the higher concentration of NaOH (10% w/w), agglomeration was taken place among the catalyst particles in which decreasing the surface area of the modified catalysts. Finally, the modified catalyst (Na2O/Fe2O3) was successfully applied as an inorganic catalyst on transesterification of coconut oil and methanol (T = 55 – 60oC, 2 h)for forming methyl esters asbiodiesel compounds. 

2016 ◽  
Vol 16 (1) ◽  
pp. 15-17
Author(s):  
Andia Andia ◽  
Adi Rahwanto ◽  
Zulkarnanin Jalil

Indonesia has a lot of mining material of iron ore that could be used for various purposes in the steel industry or for other. This research, has synthesized and characterization of hematite from local iron ore from Lhoong area by precipitation mechanism. The iron ore powder was magnetic separation with magnet then mixed with HCl and NH4OH. Then, it was dried at temperature of 150 ºC and calcinated at 500º C for 2 hours. Characterizations were perfomed using X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). As the results, it was found that the magnetic separation iron ore showed the composition of Fe2O3 (95.99%), SiO2 (2.10%). Then, by precipitation mechanism, the composition of Fe2O3 found around 96.58%. Next, the synthesis result are characterized with XRD show that the main phase is dominan in iron ore of Lhoong is hematit (Fe2O3). Scherrer calculations showed that precipitation mechanism to reducing grain size, the process of magnetic separation (58.009 µm) and the precipitation mechanism (20.950 µm.)


2021 ◽  
Vol 10 ◽  
Author(s):  
Jyoti Dhariwal ◽  
Ravina Yadav ◽  
Sheetal Yadav ◽  
Anshu Kumar Sinha ◽  
Chandra Mohan Srivastava ◽  
...  

Aim: In the present work, the preparation and catalytic activity of spinel ferrite [MFe2O4; M = Fe, Mn, Co, Cu, Ni] nanoparticles to synthesize 5-hydroxymethylfurfural (HMF) have been discussed. Background: Ferrites possess unique physicochemical properties, including excellent magnetic characteristics, high specific surface area, active surface sites, high chemical stability, tunable shape and size, and easy functionalization. These properties make them essential heterogeneous catalysts in many organic reactions. Objective: This study aims to synthesize a series of transition metal ferrite nanoparticles and use them in the dehydration of carbohydrates for 5-hydroxymethylfurfural (HMF) synthesis. Method: The ferrite nanoparticles were prepared via the co-precipitation method, and PXRD confirmed their phase stability. The surface area and the crystallite size of the nanoparticles were calculated using BET and PXRD, respectively. Result: The easily prepared heterogeneous nanocatalyst showed a significant catalytic performance, and among all spinel ferrites, CuFe2O4 revealed maximum catalytic ability. Conclusion: Being a heterogeneous catalyst and magnetic in nature, ferrite nanoparticles were easily recovered by using an external magnet and reused up to several runs without substantial loss in catalytic activity. Others: HMF was synthesized from fructose in a good yield of 71%.


2018 ◽  
Vol 56 (3) ◽  
pp. 295
Author(s):  
Nguyen Tien Thao ◽  
Nguyen Thi Nhu ◽  
Ngo Thi Thuan

Cr2O3/sepiolite samples with different loadings have been prepared through the precipitation method and characterized by several physical methods such as XRD, TEM, BET, and TGA... The as-prepared materials have large surface area, high distribution of Cr2O3 nanoxides on the nanofibrous sepiolite. The catalysts have been tested in the oxidation of benzyl alcohol with t-BuOOH. Chromium oxides were found to be active sites for the oxidation of benzyl alcohol to aldehyde. The catalytic activity varied with reaction time and temperature. The appropriate temperature is about 60-70oC with conversion of 40-60% and benzaldehyde selectivity of 90%.


2014 ◽  
Vol 556-562 ◽  
pp. 117-122 ◽  
Author(s):  
Miao Yao Jia ◽  
Wen Gui Gao ◽  
Hua Wang ◽  
Yu Hao Wang

Various CuO-ZnO-ZrO2(CZZ) catalysts for methanol synthesis from CO2 hydrogenation were prepared by co-precipitation method. Small amount of silica was incorporated into CZZ catalyst to produce these modified ternary CZZ catalysts. The effects of silica on physicochemical and catalytic properties were studied by TG-DTG,XRD,BET,N2O chemisorption,H2-TPR,NH3-TPD and CO2-TPD techniques. The results show that the properties of catalysts were strongly influenced by the content of SiO2 used as promoter. The catalytic performance for methanol synthesis from CO2 hydrogenation was evaluated. The test results show that the CZZ catalyst modified with 4 wt.% SiO2 exhibits an optimum catalytic activity. The silica improves the dispersion of CuO and its modified CZZ catalysts exhibits higher specific surface area, which were confirmed to be responsible for excellent performance of the catalysts for methanol synthesis from CO2 hydrogenation.


2013 ◽  
Vol 13 (2) ◽  
pp. 171-175 ◽  
Author(s):  
Hendro Juwono ◽  
Triyono Triyono ◽  
Sutarno Sutarno ◽  
Endang Tri Wahyuni

Biogasoline have been synthesized through catalytic hydrocracking reaction against FAMEs compounds (fatty acid methyl esters) obtained from the transesterification of Nyamplung seed oil. The performance of Al-MCM-41 and Pd/Al-MCM-41 as the catalytic hydrocracking was compared. In this research, the influence of Pd impregnation into Al-MCM-41 catalyst on the characters and catalytic activity has been evaluated. The characters determined were crystallinity by using X-Ray Diffractometer (XRD), Si/Al ratio by Inductively Coupled Plasma (ICP), the acidity by pyridine adsorption, the surface area and pore volume by surface area analyzer and the morphology by Scanning Electron Microscopy (SEM). Catalytic activity was examined for hydrocracking of free fatty acid methyl esters (FAMEs) produced from the transesterification of Nyamplung seed oil, by Hydrogen flowing. The research result showed that impregnation of Pd into Al-MCM-41 has been successfully carried out, which did not destroy the structural morphology of the catalyst. It was also discovered that the Pd impregnation could increase Si/Al ratio and the acidity but it leads to decrease in the catalyst surface area and the volume. Furthermore, Pd impregnated Al-MCM-41 showed superior activity compared to Al-MCM-41 for FAMEs hydrocracking. The superiority was indicated by higher effectiveness and yields selectiveness, that were 100% hydrocarbon composed of C9-C18 that was dominated by C12 emerging the gasoline fraction, compared of that by the results used Al-MCM-41 catalyst that were 97% hydrocarbon consisted of C8-C20 with equal abundance.


Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1461
Author(s):  
Kieran Aggett ◽  
Thomas E. Davies ◽  
David J. Morgan ◽  
Dan Hewes ◽  
Stuart H. Taylor

CeO2 catalysts were prepared by a precipitation method using either (NH4)2Ce(NO3)6 or Ce(NO3)3, as CeIV or CeIII precursors respectively. The influence of the different precursors on catalytic activity was evaluated for the total oxidation of propane with water present in the feed. The catalyst prepared using the CeIV precursor was more active for propane total oxidation. The choice of precursor influenced catalyst properties such as surface area, reducibility, morphology, and active oxygen species. The predominant factor associated with the catalytic activity was related to the formation of either CeO2.nH2O or Ce2(OH)2(CO3)2.H2O precipitate species, formed prior to calcination. The formation of CeO2.nH2O resulted in enhanced surface area which was an important factor for controlling catalyst activity.


1992 ◽  
Vol 57 (11) ◽  
pp. 2241-2247 ◽  
Author(s):  
Tomáš Hochmann ◽  
Karel Setínek

Solid acid catalysts with acid strength of -14.52 < H0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105-800 °C. Two preparation methods were used: impregnation of the calcined boehmite with 3.5 M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650 °C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerization of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yoottapong Klinthongchai ◽  
Seeroong Prichanont ◽  
Piyasan Praserthdam ◽  
Bunjerd Jongsomjit

AbstractMesocellular foam carbon (MCF-C) is one the captivating materials for using in gas phase dehydrogenation of ethanol. Extraordinary, enlarge pore size, high surface area, high acidity, and spherical shape with interconnected pore for high diffusion. In contrary, the occurrence of the coke is a majority causes for inhibiting the active sites on catalyst surface. Thus, this study aims to investigate the occurrence of the coke to optimize the higher catalytic activity, and also to avoid the coke formation. The MCF-C was synthesized and investigated using various techniques. MCF-C was spent in gas-phase dehydrogenation of ethanol under mild conditions. The deactivation of catalyst was investigated toward different conditions. Effects of reaction condition including different reaction temperatures of 300, 350, and 400 °C on the deactivation behaviors were determined. The results indicated that the operating temperature at 400 °C significantly retained the lowest change of ethanol conversion, which favored in the higher temperature. After running reaction, the physical properties as pore size, surface area, and pore volume of spent catalysts were decreased owing to the coke formation, which possibly blocked the pore that directly affected to the difficult diffusion of reactant and caused to be lower in catalytic activity. Furthermore, a slight decrease in either acidity or basicity was observed owing to consumption of reactant at surface of catalyst or chemical change on surface caused by coke formation. Therefore, it can remarkably choose the suitable operating temperature to avoid deactivation of catalyst, and then optimize the ethanol conversion or yield of acetaldehyde.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 88
Author(s):  
Diana García-Pérez ◽  
Maria Consuelo Alvarez-Galvan ◽  
Jose M. Campos-Martin ◽  
Jose L. G. Fierro

Catalysts based on zirconia- and alumina-supported tungsten oxides (15 wt % W) with a small loading of platinum (0.3 wt % Pt) were selected to study the influence of the reduction temperature and the nature of the support on the hydroisomerization of n-dodecane. The reduction temperature has a major influence on metal dispersion, which impacts the catalytic activity. In addition, alumina and zirconia supports show different catalytic properties (mainly acid site strength and surface area), which play an important role in the conversion. The NH3-TPD profiles indicate that the acidity in alumina-based catalysts is clearly higher than that in their zirconia counterparts; this acidity can be attributed to a stronger interaction of the WOx species with alumina. The PtW/Al catalyst was found to exhibit the best catalytic performance for the hydroisomerization of n-dodecane based on its higher acidity, which was ascribed to its larger surface area relative to that of its zirconia counterparts. The selectivity for different hydrocarbons (C7–10, C11 and i-C12) was very similar for all the catalysts studied, with branched C12 hydrocarbons being the main products obtained (~80%). The temperature of 350 °C was clearly the best reduction temperature for all the catalysts studied in a trickled-bed-mode reactor.


Author(s):  
Nuni Widiarti ◽  
Hasliza Bahruji ◽  
Holilah Holilah ◽  
Yatim Lailun Ni’mah ◽  
Ratna Ediati ◽  
...  

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