scholarly journals FORMULASI KATALIS BIFUNGSIONAL SINTESA DME SATU TAHAP

2020 ◽  
Vol 13 (2) ◽  
Author(s):  
Ade Syafrinaldy ◽  
Zulaicha Dwi Hastuti
Keyword(s):  
Methanol Synthesis ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Molar Ratio ◽  
Synthesis Process ◽  
Methanol Dehydration ◽  
Commercial Catalyst ◽  
Methanol Synthesis Catalyst ◽  
Co Conversion ◽  
The Right

This research is aiming to formulate the most appropriate catalyst which is expected to be able to directthe reaction to form Dimethyl Ether (DME) in direct synthesis process using dual catalyst. It iscommonly known that DME can be formulated from synthetic gasses reaction, H2 and CO. Theprocess might be gone through indirect synthesis, methanol synthesis and dehydration, or directsynthesis in which both rections take place in one reactor. Both processes, indirect or direct synthesis,each would be needed the right catalyst. Dual catalyst is prepared by mixing physically methanolsynthesis catalyst and methanol dehydration to form DME.As methanol dehydration catalyst, we makeuse of HZSM-5 with Si/Al ratio of 25 and 90. This HZSM-5 is firstly calcined for 6 hours at 500°C. Thetemperature is raised to 500°C from ambient with pace of 5°C/min. The methanol synthesis catalyst isbased on CuZnAl, made by copresipitation method from Cu(NO3)2.3H2O; Zn(NO3)2.4H2O andAl(NO3)2.9H2O. The catalyst was then calcined at 350 ° C for 6 hours, then reduced by hydrogen 10 ml /minute and nitrogen 90 ml / min at 240 ° C, atmospheric pressure for 10 hours to remove the Ocomponent in the catalyst. The catalyst that has been prepared is CuZnAl with a ratio of 4: 3: 1; 5: 3: 1and 6: 3: 1. The ratio of the two catalysts is 2: 1 for Cu / Zn / Al2O3: HZSM-5. The catalytic activity test iscarried out using a continuous tubular fixed-bed microactivity reactor. The reaction is carried out at apressure between 3 - 4 MPa and a temperature in the range of 200 - 300 ° C. T The flow rate of thereactant gas is controlled by a mass flow controller, with a mass of 1 g of catalyst. Through the catalyticactivity test, the best methanol synthesis was given by CuZnAl catalyst with a 5: 3: 1 molar ratio, whichresulted in a CO conversion of 19.66% greater than the commercial catalyst of CZA-Sudchemie of15.62%. As for dehydration of methanol, the best result was given by Sudchemie-ZSM-5 catalyst withSi /Al 25 ratio resulting in higher DME concentration (0.90%) than Si /Al 90 ratio (0.45%).Keywords : direct synthesis, methanol synthesis, methanol dehydration, dual catalyst, CO conversion

scholarly journals Synthesis of dimethyl ether using a fixed bed of dual catalyst for methanol synthesis and its dehydration

2019 ◽  
Vol 268 ◽  
pp. 07003
Author(s):  
Aisyah Ardy ◽  
Jenny Rizkiana ◽  
Melia Laniwati ◽  
Herri Susanto
Keyword(s):  
Dimethyl Ether ◽  
Methanol Synthesis ◽  
Gas Flow ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
High Concentration ◽  
Catalyst Composition ◽  
Methanol Synthesis Catalyst ◽  
Methanol Formation

Experimental study on direct synthesis of DME (dimethyl ether) has been conducted using tubular reactor. The synthesis of DME was performed with two commercial catalysts, ie methanol synthesis catalyst (M151, Cu-based) and methanol dehydration catalyst (γAl2O3). A mixture of H2, CO, and N2 was used as a model for synthesis gas. Gas flow rate was set at 20 mL/min (5 bar and 240oC). The reaction held at: pressure of 5 bar and a temperature of 240°C. This experiment was conducted by arranging a series of two types of catalysts in a fixed bed reactor. The methanol synthesis catalyst was placed in the upstream to ensure the reaction of methanol formation, then proceed with dehydration of methanol to DME. The objective of this experiment was to find out the best dual catalyst composition to produce a high concentration of DME. The experiment has shown that the best combination of methanol catalyst to dehydration catalyst was a mixture of 20% methanol catalyst (ratio 1/4). CO conversion was 62% and the product ratio of DME/methanol was 40%.

scholarly journals Effect of Pressure and Syngas Composition on Direct Synthesis of Dimethyl Ether using Dual Bed Catalyst

2019 ◽  
Vol 19 (1) ◽  
pp. 38
Author(s):  
Aisyah Ardy ◽  
Jenny Rizkiana ◽  
Melia Laniwati Gunawan ◽  
Herri Susanto
Keyword(s):  
Dimethyl Ether ◽  
Direct Synthesis ◽  
Catalyst Activity ◽  
Fixed Bed ◽  
Commercial Catalyst ◽  
Fixed Temperature ◽  
Effect Of Pressure ◽  
Co Conversion ◽  
Dual Bed ◽  
Synthesis Of Dimethyl Ether

National General Energy Plan of Indonesia 2017 (RUEN 2017) stated that dimethyl ether (DME) is appointed as a blending of LPG to reduce LPG imports. DME can be made with two reaction pathways, namely direct synthesis and indirect synthesis. The objective of this study was to determine the effect of pressure and syngas composition on the direct synthesis of DME using dual fixed bed catalyst. The research was carried out with two types of catalyst: M-xxx as a commercial catalyst for methanol synthesis and γ-Al2O3 as catalyst for dehydration of methanol to DME. The later was prepared in our Laboratory of Chemical Reaction Engineering and Catalysis, ITB. The dual catalyst experiment was carried out at 5 and 7 bars, and a fixed temperature of 240oC. The mass ratio of the M-xxx to γ-Al2O3, so-called M/D ratios, were varied from 1/9 to 9/1. Two type of syngas were used, i.e. SA containing only H2 and CO with a SN of 2,3 and SB containing 4% CO2 with SN of 1,8. The dual bed with a M/D ratio of 1/4 gave a CO conversion up to 62% at 5 bars and 240oC (SA). As pressure increased, the conversion of CO and H2 increases to 85% and 83% at 7 bar and 240oC (SA). The presence of CO2 (SB) decreases catalyst activity, as indicated by the decrease in conversion of CO and H2 to 56% and 54%, at 7 bar and 240oC.

scholarly journals Direct synthesis of light olefins from synthesis gas utilizing composite catalyst of methanol synthesis catalyst and zeolite.

1986 ◽  
Vol 29 (2) ◽  
pp. 178-182
Author(s):  
Tsuneji SANO ◽  
Kiyomi OKABE ◽  
Hiroshi SHOJI ◽  
Kenji SAITO ◽  
Hideo OKADO ◽  
...  
Keyword(s):  
Synthesis Gas ◽  
Methanol Synthesis ◽  
Direct Synthesis ◽  
Light Olefins ◽  
Composite Catalyst ◽  
Methanol Synthesis Catalyst

Methanol Synthesis in a Slurry Phase Reactor over Cu/ZnO/Al2O3 Catalyst

2014 ◽  
Vol 931-932 ◽  
pp. 27-31 ◽  
Author(s):  
Kuntima Krekkeitsakul ◽  
Thanes Utistham ◽  
Unalome Wetwatana Hartley
Keyword(s):  
Surface Area ◽  
Residence Time ◽  
Methanol Synthesis ◽  
Batch Reactor ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Mixed Gas ◽  
Reactor Model ◽  
Co Conversion ◽  
Bet Analysis

Methanol synthesis from synthesis gas (syngas, a mixture of hydrogen (H2) and carbon monoxide (CO)) in the presence of copper/zinc oxide/alumina catalyst (Cu/ZnO/Al2O3) was investigated using semi-batch reactor. The process was operated at 280 °C under pressure 40 bar in a slurry reactor (Parr reactor model 4848). The catalyst weight, syngas molar ratio and residence time were optimized for methanol synthesis. Cu/ZnO/Al2O3catalyst was prepared by a two-step surfactant assisted precipitation method using polyethylene glycol (PEG 6000). The catalysts surface area, crystallinity, reducibility and morphology were characterized by BET, XRD, H2-TPR and SEM-EDS, respectively. The BET analysis indicated that the catalyst calcined at 300 °C gave the highest surface area (99.67 m2/g). The crystallite size of Cu in Cu/ZnO/Al2O3catalyst was estimated to be 14.14 nm., after adding the surfactants. The maximum methanol yield (607.53) was achieved after 24 hours of residence time using 5 g of the catalyst under a stream of 2 to 1 molar ratio of H2and CO reactive mixed gas. Under these conditions, 38.26% of CO conversion and 93.11% of selectivity to methanol were achieved. When the residence time was decreased to 12 hours with molar ratio of 0.5 H2to 1 CO, the yield of methanol was 388.11, with a CO conversion of 38.53% and selectivity to methanol of 90.77%.

Facile Structure Tuning of a Methanol-Synthesis Catalyst towards the Direct Synthesis of Dimethyl Ether from Syngas

ChemCatChem ◽  
2017 ◽  
Vol 9 (24) ◽  
pp. 4484-4489 ◽  
Author(s):  
Cheonwoo Jeong ◽  
Hyungwon Ham ◽  
Jong Wook Bae ◽  
Dong-Chang Kang ◽  
Chae-Ho Shin ◽  
...  
Keyword(s):  
Dimethyl Ether ◽  
Methanol Synthesis ◽  
Direct Synthesis ◽  
Methanol Synthesis Catalyst ◽  
Synthesis Of Dimethyl Ether

A CuZnAl-Based Hybrid Material for the Direct Synthesis of Dimethyl Ether from Syngas

2012 ◽  
Vol 457-458 ◽  
pp. 261-264 ◽  
Author(s):  
Zhuo Li ◽  
Cheng Yang ◽  
Jian Qing Li ◽  
Jin Hu Wu
Keyword(s):  
Dimethyl Ether ◽  
Hybrid Material ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Synthesis Process ◽  
Impregnation Method ◽  
Active Components ◽  
Co Precipitation ◽  
Synthesis Of Dimethyl Ether

A CuZnAl-based hybrid material was prepared by co-precipitation impregnation method using the active components of methanol synthesis material and pseudo-boehmite as the precursors. The as-prepared material was evaluated for the direct synthesis of dimethyl ether (DME) from syngas in a pressurized continuous flow fixed-bed reactor system. It was revealed that the hybrid material showed high activity and selectivity after an induced period, i.e. the CO conversion and DME selectivity reached as high as 81% and 67%, respectively. Moreover, it was observed that there was only slight carbon which could be eliminated rather than graphite carbon deposited on the material after run for 150 h, indicating its good stability for the direct synthesis process .

Dimethyldisulphide Hydrodesulphurization on NiCoMo / Al2O3 Catalyst

2017 ◽  
Vol 68 (7) ◽  
pp. 1496-1500
Author(s):  
Rami Doukeh ◽  
Mihaela Bombos ◽  
Ancuta Trifoi ◽  
Minodora Pasare ◽  
Ionut Banu ◽  
...  
Keyword(s):  
Good Accuracy ◽  
Fixed Bed ◽  
Continuous System ◽  
Space Velocity ◽  
Molar Ratio ◽  
Catalytic Reactor ◽  
Liquid Hourly Space Velocity ◽  
Hydrodesulfurization Process ◽  
Al2o3 Catalyst ◽  
Simplified Kinetic Model

Hydrodesulphurization of dimethyldisulphide was performed on Ni-Co-Mo /�-Al2O3 catalyst. The catalyst was characterized by determining the adsorption isotherms, the pore size distribution and the acid strength. Experiments were carried out on a laboratory echipament in continuous system using a fixed bed catalytic reactor at 50-100�C, pressure from 10 barr to 50 barr, the liquid hourly space velocity from 1h-1 to 4h-1 and the molar ratio H2 / dimethyldisulphide 60/1. A simplified kinetic model based on the Langmuir�Hinshelwood theory, for the dimethyldisulphide hydrodesulfurization process of dimethyldisulphide has been proposed. The results show the good accuracy of the model.

XGBoost and Network Analysis for Prediction of Proteins Affecting Insulin based on Protein Protein Interactions

2020 ◽  
pp. 253-262
Author(s):  
Mohammad Hamim Zajuli Al Faroby ◽  
Mohammad Isa Irawan ◽  
Ni Nyoman Tri Puspaningsih
Keyword(s):  
Protein Interactions ◽  
Interaction Analysis ◽  
Synthesis Process ◽  
Gradient Boosting ◽  
Protein Protein Interactions ◽  
Central Function ◽  
Extreme Gradient Boosting ◽  
Main Protein ◽  
The Right ◽  
Roc Score

Protein Interaction Analysis (PPI) can be used to identify proteins that have a supporting function on the main protein, especially in the synthesis process. Insulin is synthesized by proteins that have the same molecular function covering different but mutually supportive roles. To identify this function, the translation of Gene Ontology (GO) gives certain characteristics to each protein. This study purpose to predict proteins that interact with insulin using the centrality method as a feature extractor and extreme gradient boosting as a classification algorithm. Characteristics using the centralized method produces  features as a central function of protein. Classification results are measured using measurements, precision, recall and ROC scores. Optimizing the model by finding the right parameters produces an accuracy of  and a ROC score of . The prediction model produced by XGBoost has capabilities above the average of other machine learning methods.

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