scholarly journals Catalytic Methanol to Hydrocarbons Transformation Particularities in Case of Micro Structured Flows Application

2022 ◽  
Vol 8 (1) ◽  
pp. 17-24
Author(s):  
R. Brovko ◽  
L. Mushinskii ◽  
V. Doluda
Keyword(s):  
Fluidized Bed ◽  
Reaction Temperature ◽  
Feed Rate ◽  
Average Diameter ◽  
Predominant Formation ◽  
Medium Size ◽  
Scale Production ◽  
Liquid Hydrocarbons ◽  
Monolithic Catalyst ◽  
Methanol Feed Rate

The methanol into hydrocarbons transformation is a complex catalytic reaction accompanied by the formation of a wide range of hydrocarbons and proceeding on the surface of acid sites of various zeolites. Zeolite H-ZSM-5 considered to be most often used catalyst for this process. H-ZSM-5 is a highly dispersed material with a crystal diameter of 1–20 microns, which complicates its direct use in reactors with a fixed catalyst bed due to the high hydraulic pressure drop of the catalytic bed. Traditionally in industry, this issue is solved by using complex reactor systems with a fluidized bed, which is justified for large-scale production. In small and medium-size plants, the use of fluidized bed systems is not economically feasible. One of the possible solutions to this problem is the use of a monolithic catalyst with a supported layer of H-ZSM-5 zeolite. This article presents a study of the catalytic activity of a zeolite-containing microstructured monolith in methanol into hydrocarbons transformation. The monolith was synthesized by pressing a zeolite-containing mass followed by drying, calcining, and secondary growth of the zeolite on the monolith surface. A sample of a monolith with an average channel diameter of 0.5, 1.0, 1.5, 2.0 mm were synthesized this way. Samples of the microstructured catalyst were tested at varying temperatures from 250 to 450 °C and at varying the specific methanol feed rate from 0.65 to 2.3 kg (MeOH)/(kg (Cat) h). For this purpose, the monolithic catalyst was placed in a reactor for testing microstructured catalysts, which consisted of a pump, a temperature controller, a catalytic reactor, a condenser, a separating funnel, and a chromatograph. Varying the conditions showed that for the preferential production of gaseous C1–C4 hydrocarbons, it is advisable to carry out the reaction under the following conditions: the average diameter of the catalyst channels is 2 mm, the reaction temperature is 350 °C, the methanol feed rate is 1.65 kg (MeOH)/(kg (Cat) h). For the predominant formation of liquid hydrocarbons of the C5–C8 fraction, it is advisable to carry out the transformation of methanol into hydrocarbons under the following conditions: the average diameter of the catalyst channels is 1 mm, the reaction temperature is 350 °C, the methanol feed rate is 0.65 kg (MeOH) / (kg (Cat) h). For the predominant formation of liquid hydrocarbons of the C9–C12 fraction, it is advisable to carry out the transformation of methanol into hydrocarbons under the following conditions: the average diameter of the catalyst channels is 0.5 mm, the reaction temperature is 350 °C, and the methanol feed rate is 0.65 kg (MeOH) / (kg (Cat) h).

scholarly journals PECULIARITIES OF SMALL STRAINED ALICYCLE COMPOUNDS FORMATION IN CATALYTIC TRANSFORMATION OF METHANOL OVER ZEOLITE H-ZSM-5

2018 ◽  
Vol 61 (12) ◽  
pp. 74-80
Author(s):  
Valentin Yu. Doluda ◽  
Alexey V. Bykov ◽  
Mikhail G. Sulman ◽  
Alexander I. Sidorov ◽  
Natalia V. Lakina ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Carbon Concentration ◽  
Photoelectron Spectroscopy ◽  
Feed Rate ◽  
Accumulation Rate ◽  
Formation Rate ◽  
Carbon Surface ◽  
Catalytic Transformation ◽  
X Ray ◽  
Methanol Feed Rate

The article presents the results of strained hydrocarbons formation study during the catalytic transformation of methanol into hydrocarbons on zeolite H-ZSM-5. The formation of the following strained cyclic compounds was determined: 1,1-dimethylcyclopropane, 1,2-dimethyl-cyclopropane, 1,1,2-trimethylcyclopropane, 1,2,3-trimethylcyclopropane, 1,1,2,2-tetramethylcyclo-propane, 1,1,2 , 3-tetramethylcyclopropane. The non-stationary character of strained cyclic hydrocarbons formation with a pronounced hydrocarbons formation rate maximum and subsequent deactivation of the catalyst was found. The temperature effect on strained hydrocarbons yield was evaluated. Thus, with an increase in the process reaction temperature up to 400 °C, a maximum of strained hydrocarbons accumulation rate was achieved as 8-8.5 g(Hyd)/(kg(Cat)·h) on 350 h of reaction, and a further increase in the reaction temperature leads to a decrease in the strained hydrocarbons accumulation rate. The effect of the methanol feed rate on the strained hydrocarbons formation rate was also studied. An increase in the methanol feed rate from 0.02 ml/min to 0.16 ml/min results in increase in the strained hydrocarbons formation rate up to 37 g (Hyd)/(kg(Cat)·h). The article presents results of H-ZSM-5 physicochemical study used by ammonia chemisorption, nitrogen phisisorption, X-ray photoelectron spectroscopy. Physicochemical studies of catalyst samples after the methanol transformation process to form strained hydrocarbons showed a twofold decrease in the number of acid sites from 1.2 mmol(NH3)/g (sample) to 0.3 mmol (NH3)/g(sample) and a significant decrease in surface area of micropores from 294 m2/g for the initial sample to 16 m2/g for the sample after the reaction. The X-ray diffraction spectroscopy method showed that the composition of the catalysts H-ZSM-5 surface includes carbon, oxygen, silicon and aluminum. Carbon concentration was found to be 4.3 at.% on the surface of the initial catalyst. While the carbon concentration increases up to 14.1 at.% during the reaction. Also oxygen content on the catalysts surface decreases from 59.9 to 53.4 at%, silica concentration decreases from 35.5 to 32.1 at.%. The following indicates the formation of a carbon surface layer over the catalysts.

Parameter selection of Polystyrene-Dietilenetriaminepenta acetate Resin Synthesis for the separation of rare Earth Elements by using Plackett-Burman Experimental Design

2021 ◽  
pp. 5629-5634
Author(s):  
Herman Herman ◽  
Bohari Yusuf ◽  
Laode Rijai ◽  
Hadi Kuncoro ◽  
Anni Anggraeni ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Chemical Properties ◽  
Ammonia Concentration ◽  
Yield Ratio ◽  
Scale Production ◽  
Separation And Purification ◽  
Diethylene Triamine ◽  
Stirring Rate ◽  
Volume Reaction ◽  
Selection Of

The development of the separation method has an essential role in developing science and technology for the separation and purification of an element or compound from other mixtures based on differences in physical and chemical properties. This research is more focused on the selection parameters of polystyrene-based resin production using diethylene triamine penta-acetate (DTPA) light, which used as a prototype for improved scale production. The Plackett-Burman design was used to select variables that have significant influence in Methylaminopolystyrene-Diethylenetriaminepentaacetate (MAP-DTPA) resin synthesis. Eleven variables such as mol ratio of Methylamino Polystyrene and diethylene triamine penta-acetate ligands, solvent volume, reaction time, stirring rate, reaction temperature, total volume, reaction pH, incubation time, ammonia concentration, and the addition of methanol were carried out for the selection of parameters or variables in the process of MAP-DTPA resin synthesis through a statistical approach in studies for design experiments using Software Design Expert 9.0.6.2. Of the eleven variables in resin synthesis obtained, six variables have a positive influence on the yield ratio value (percent yield ratio) of MAP-DTPA resin are the mol ratio of MAP and DTPA, Stirring Rate, reaction temperature, total volume, degree of acidity, and ammonia concentration.

A Variable Feed Rate Mechanism for Fluidized Bed Asbestos Generators

AIHAJ ◽  
1985 ◽  
Vol 46 (1) ◽  
pp. 24-27 ◽  
Author(s):  
R.G. SUSSMAN ◽  
J.M. GEARHART ◽  
M. LIPPMANN
Keyword(s):  
Fluidized Bed ◽  
Feed Rate ◽  
Variable Feed Rate ◽  
Rate Mechanism

Pilot-Scale Study on Improving SNCR Denitrification Efficiency by Using Gas Additives

2018 ◽  
Vol 17 (3) ◽  
Author(s):  
Zhou Weiqing ◽  
Liu Meng ◽  
Huang Baohua ◽  
Qiu Xiaozhi
Keyword(s):  
Low Temperature ◽  
Fluidized Bed ◽  
Reaction Temperature ◽  
Temperature Region ◽  
Circulating Fluidized Bed ◽  
Catalytic Reduction ◽  
Pilot Scale ◽  
Incomplete Oxidation ◽  
Optimal Value

Abstract The experiment of improving Selective Non-Catalytic Reduction (SNCR) denitrification efficiency with gas additives (CH4 and C3H8) was carried out in the 50 kW circulating fluidized bed (CFB) pilot-scale equipment. The results show that the denitrification efficiency can reach 20 % when the reaction temperature is 650 °C, and the optimum mole ratio of C3H8/NH3 is 0.5. The denitrification efficiency can exceed 50 % when the mole ratio of C3H8/NH3 is 0.4 and the reaction temperature is 720 °C. However, the CH4 additive does not promote denitrification at this temperature. When the reaction temperature is 760 °C, the optimum denitrification efficiency of CH4 is 60 %, and the required CH4/NH3 is 0.8. Once the amount of CH4 exceeds the optimal value, the denitrification efficiency is suppressed. In addition, the concentrations of N2O and CO in the gas increase significantly with an increase of gas additives. Due to the incomplete oxidation of C3H8, a large amount of C2H4 is produced in the low-temperature region (< 750 °C) of SNCR.

Synthesis and Thermal Stability of HfO2 Nanoparticles

2010 ◽  
Vol 1256 ◽  
Author(s):  
Girija Shankar Chaubey ◽  
Yuan Yao ◽  
Julien Pierre Amelie Makongo Mangan ◽  
Pranati Sahoo ◽  
Pierre F. P. Poudeu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Large Scale ◽  
Average Diameter ◽  
Scale Production ◽  
Simple Method ◽  
Good Thermal Stability ◽  
Large Scale Production

AbstractA simple method is reported for the synthesis of monodispersed HfO2 nanoparticles by the ammonia catalyzed hydrolysis and condensation of hafnium (IV) tert-butoxide in the presence of surfactants at room temperature. Transmission electron microscopy shows faceted nanoparticles with an average diameter of 3-4 nm. As-synthesized nanoparticles are amorphous in nature and crystallize upon moderate heat treatment. The HfO2 nanoparticles have a narrow size distribution, large specific surface area and good thermal stability. Specific surface area was about 239 m2/g on as-prepared nanoparticle samples while those annealed at 500 °C have specific surface area of 221 m2/g indicating that there was no significant increase in particle size. This result was further confirmed by TEM images of nanoparticles annealed at 300 °C and 500 °C. X-ray diffraction studies of the crystallized nanoparticles revealed that HfO2 nanoparticles were monoclinic in structure. The synthetic procedure used in this work can be readily modified for large scale production of monodispersed HfO2 nanoparticles.

scholarly journals Large-Scale Synthesis of Silver Nanoparticles by Aqueous Reduction for Low-Temperature Sintering Bonding

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Qiu Xiliang ◽  
Cao Yang ◽  
Lin Tiesong ◽  
He Peng ◽  
Wang Jun ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Low Temperature ◽  
Reaction Temperature ◽  
Large Scale ◽  
Reduction Process ◽  
Average Diameter ◽  
Influential Factors ◽  
Low Temperature Sintering ◽  
Mass Ratio ◽  
Sintering Characteristics

Silver nanoparticles with average diameter of 22.4 nm were prepared by aqueous reduction method for low-temperature sintering bonding application. The reaction temperature and PVP concentration, which are the influential factors of nanoparticle characteristics, were investigated during reduction process. In our research, monodispersity of nanoparticles was remarkably improved while unfavorable agglomeration was avoided with the AgNO3/PVP mass ratio of 1 : 4 at the reaction temperature 30°C. Besides, copper pads were successfully bonded using sintering paste employing fresh silver nanoparticles with diameter of 20~35 nm at 200°C. In addition, after morphology of the bonding joint was analysed by scanning electron microscope (SEM), the porous sintering characteristics were confirmed.

Catalytic Conversion of Octanoic Acid over HZSM-5 Catalyst

2014 ◽  
Vol 926-930 ◽  
pp. 60-63
Author(s):  
Yi Bin Liu ◽  
Yu Zhen Li ◽  
Xue Ding ◽  
Zhao Jun Chen
Keyword(s):  
Fluidized Bed ◽  
Reaction Temperature ◽  
Octanoic Acid ◽  
Catalytic Conversion ◽  
Fluidized Bed Reactor ◽  
Product Distribution ◽  
Reactor System

Catalytic conversion experiment of octanoic acid over HZSM-5 catalyst was carried out in a fixed fluidized bed reactor system. The effects of reaction temperature and catalyst to oil ratio on product distribution were investigated. The results showed that temperature influenced the LCO, gasoline and CO yields obviously. LCO yield decreased while CO yield increased with increasing reaction temperature. Gasoline yield reached maximum at 450 oC. CO is the major oxygenated product, and the yield increased linearly with increasing catalyst to oil ratio..

scholarly journals Characterization and performance of W-ZSM-5 and loaded Cu/ZsM-5 catalysts

2018 ◽  
Vol 4 (1) ◽  
pp. 137
Author(s):  
Didi Dwi Anggoro ◽  
Nor Aishah Saidina Amin
Keyword(s):  
Metal Oxides ◽  
Surface Area ◽  
Methane Oxidation ◽  
Metal Surface ◽  
Reaction Temperature ◽  
Methane Conversion ◽  
Liquid Hydrocarbons ◽  
Olefin Oxidation ◽  
Metal Surface Area ◽  
And Performance

The metal oxides with sufficiently high dehydrogenation and low olefin oxidation activities reduces the acidity of ZSM-5. As a result, the metal containing ZSM-5 can produce higher hydrocarbons in methane oxidation. Many researchers studied the applicability of HZSM-5 and modify ZSM-5 to methane conversion to liquid hydrocarbons but result of their research still lead to low conversion and selectivity. The modified HZS-5 by loading with Tungsten (W) enhanced its heat resistant performance, and the high reaction temperature (800ºC) did not lead to the loss of W component by sublimation. The loading of HZSM-5 with Tungsten and Cooper (Cu) resulted in an increment in the methane conversion, CO2 and C5+ selectivities. In contrast, CO, C2-3, and H2O selectivities were reduced. The process to convert methane to liquid hydrocarbons (C5+) was dependent on the metal surface area and the acidity of zeolite. The high methane conversion and C5+ selectivity, and low H2O selectivity are obtained by using W/3.0Cu/HZSM-5.  Keywords : Characterization W-ZSM-5, Modified HZSM-5, Tungsten, Copper, Methane  Abstrak  Logam oksida dengan kemampuan dehidrogenasi yang tinggi dan aktifasi oksidasi olefin berkurang dengan sifat keasaman dari ZSM-5. Sebagai hasilnya, ZSM-5 yang mengandung logam dapat memproduksi hidrokarbon rantai panjang dari oksidasi gas metana. Telah banyak para peneliti mempelajari kemampuan HZSM-5 dan ZSM-5 yang telah dimodifikasi untuk mengubah gas metana menjadi hidrokarbon cair tetapi hasil konversi dan selektivitasnya masih rendah. Modifikasi HZSM- 5 dengan penambahan logam Tungsten (W) meningkatkan daya tahan panas dan pada reaksi suhu tinggi (800ºC) tidak menyebabkan hilangnya logam W dikarenakan proses sublimasi. Penambahan logam Tungsten dan Copper (Cu) menyebabkan meningkatnya konversi metana, selektifitas CO2 dan C5+ Sebaliknya, selektifitas CO,C2-3, dan H2O menurun. Proses konversi metana menjadi hidrokarbon cair ditentukan oleh luas permukaan logam dan sifat keasaman dari zeolite.  Penggunaan katalis W/3.0Cu/HZSM-5 menghasilkan konversi metana dan selektifitas C5+ tinggi dan selektifitas H2O rendah.  Kata kunci : Karakterisasi W-ZSM-5, Modifikasi HZSM-5, Tungsten, Copper, Metana

scholarly journals Influence of drying conditions on process properties and parameter identification for continuous fluidized bed spray agglomeration

2018 ◽  
Author(s):  
Gerd Strenzke ◽  
Ievgen Golovin ◽  
Maximilian Wegner ◽  
Stefan Palis ◽  
Andreas Bück ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Feed Rate ◽  
Continuous Process ◽  
Binder Content ◽  
Balance Model ◽  
Process Stability ◽  
Primary Particles ◽  
Bed Agglomeration ◽  
Drying Conditions ◽  
Population Balances

Agglomeration is a particle formulation process in which at least two primary particles are combined to form a new one. The growth of agglomerates depends on interactions of particles covered with wet spots that generated by depositions of binder droplets. This work experimentally compares the influence of external feed rate and sprayed binder content on product properties and process stability with internal separation at different drying conditions. Due to the identification of parameters a populations balance model (PBM) is developed. The PBM includes the agglomeration kernel function, which characterizes the kinetics, i.e. the rate at which primary particles build agglomerates. Keywords: spray fluidized bed agglomeration; drying; continuous process; internal separation; population balances

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