Studies on Pyrolysis Kinetic of Newspaper Wastes in a Packed Bed Reactor: Experiments, Modeling, and Product Characterization

Newspaper waste was pyrolysed in a 50 mm diameter and 640 mm long reactor placed in a packed bed pyrolyser from 573 K to 1173 K in nitrogen atmosphere to obtain char and pyro-oil. The newspaper sample was also pyrolysed in a thermogravimetric analyser (TGA) under the same experimental conditions. The pyrolysis rate of newspaper was observed to decelerate above 673 K. A deactivation model has been attempted to explain this behaviour. The parameters of kinetic model of the reactions have been determined in the temperature range under study. The kinetic rate constants of volatile and char have been determined in the temperature range under study. The activation energies 25.69 KJ/mol, 27.73 KJ/mol, 20.73 KJ/mol and preexponential factors 7.69 min−1, 8.09 min−1, 0.853 min−1of all products (solid reactant, volatile, and char) have been determined, respectively. A deactivation model for pyrolysis of newspaper has been developed under the present study. The char and pyro-oil obtained at different pyrolysis temperatures have been characterized. The FT-IR analyses of pyro-oil have been done. The higher heating values of both pyro-products have been determined.

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Studies on Pyrolysis Kinetic of Newspaper Wastes in a Packed Bed Reactor: Experiments, Modeling, Product Characterization

Thermochemical Waste Treatment ◽

10.1201/b19938-15 ◽

2016 ◽

pp. 197-220

Keyword(s):

Packed Bed ◽

Packed Bed Reactor ◽

Product Characterization ◽

Pyrolysis Kinetic

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Studies on Pyrolysis Kinetic of Newspaper Wastes in a Packed Bed Reactor: Experiments, Modeling, and Product Characterization

Thermochemical Waste Treatment ◽

10.1201/b19983-15 ◽

2017 ◽

pp. 197-220

Author(s):

Aparna Sarkar ◽

Sudip De Sarkar ◽

Michael Langanki ◽

Ranjana Chowdhury

Keyword(s):

Packed Bed ◽

Packed Bed Reactor ◽

Product Characterization ◽

Pyrolysis Kinetic

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Influence of Oxygen and Titanium Modification of AlN Surface on the Properties of Direct Bonded AlN-Cu Joints

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1537 ◽

2006 ◽

Vol 45 ◽

pp. 1537-1542 ◽

Cited By ~ 1

Author(s):

W. Olesinska ◽

D. Kalinski ◽

M. Chmielewski

Keyword(s):

Ion Implantation ◽

Thermal Oxidation ◽

Barrier Layer ◽

Oxidation Process ◽

Isothermal Oxidation ◽

Nitrogen Atmosphere ◽

Phase Changes ◽

Process Temperature ◽

Experimental Conditions ◽

Temperature Range

The paper presents the results concerning the formation of a ‘barrier’ layer on AlN ceramic during its joining with copper by the Copper Direct Bonding (CDB) technique. Prior to the joining, the AlN surface was modified by isothermal oxidation or by titanium ion implantation. The effects of the oxidation process temperature were examined within the temperature range from 673 to 1473K. The surface of the ceramic was modified by titanium ion implantation at various ion doses and various accelerating voltages. The modified ceramic was joined with oxidized copper in a nitrogen atmosphere with about 1.5ppm of oxygen, using a belt-type furnace at a temperature of 1323K. The microstructure and phase changes induced on the surfaces of the joints were examined. The modification yielded a ‘barrier’ layer (TiN), which ensured a continuous pore-less contact between the materials being joined. The results obtained under all the experimental conditions indicate that the implantation gives better effects than thermal oxidation. Ion implantation seems to be ideally suited for these purposes. The preferential dose appears to be 5*E16ions/cm2 and the preferential accelerating voltage – 15kV.

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Membrane Reactor for Methanol Synthesis Using Si-Rich LTA Zeolite Membrane

Membranes ◽

10.3390/membranes11070505 ◽

2021 ◽

Vol 11 (7) ◽

pp. 505

Author(s):

Masahiro Seshimo ◽

Bo Liu ◽

Hey Ryeon Lee ◽

Katsunori Yogo ◽

Yuichiro Yamaguchi ◽

...

Keyword(s):

Methanol Synthesis ◽

Membrane Reactor ◽

Synthesis Method ◽

Packed Bed ◽

Zeolite Membrane ◽

Packed Bed Reactor ◽

Co2 Conversion ◽

Experimental Conditions ◽

Reaction Field ◽

Lta Zeolite

We successfully demonstrated the effect of a membrane reactor for methanol synthesis to improve one-pass CO2 conversion. An Si-rich LTA membrane for dehydration from a methanol synthesis reaction field was synthesized by the seed-assisted hydrothermal synthesis method. The H2O permselective performance of the membrane showed 1.5 × 10−6 mol m−2 s−1 Pa−1 as H2O permeance and around 2,000 as selectivity of H2O/MeOH at 473 K. From the results of membrane reactor tests, the CO2 conversion of the membrane reactor was higher than that of the conventional packed-bed reactor under the all of experimental conditions. Especially, at 4 MPa of reaction pressure, the conversion using the membrane reactor was around 60%. In the case of using a packed-bed reactor, the conversion was 20% under the same conditions. In addition, the calculated and experimental conversion were in good agreement in both the case of the membrane reactor and packed-bed reactor.

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Simulation of methanol production from residual biomasses in a Cu/ZnO/Al2O3 packed bed reactor

Revista Facultad de Ingeniería Universidad de Antioquia ◽

10.17533/udea.redin.20200907 ◽

2020 ◽

Author(s):

Carlos Esteban Aristizabal-Alzate ◽

Andrés Felipe Vargas-Ramírez ◽

Pedro Nel Alvarado-Torres

Keyword(s):

Pressure Drop ◽

Heterogeneous System ◽

Catalyst Deactivation ◽

Packed Bed ◽

Packed Bed Reactor ◽

Deactivation Model ◽

Alcohol Production ◽

Methanol Production ◽

Ratio Effect ◽

Agent Selection

This article aims to simulate an algorithm constructed in MATLAB to represent the catalytic conversion of SYNGAS into methanol in a packed-bed reactor, based on chemical kinetics for a heterogeneous system with a Cu/ZnO/Al2O3 as a catalyst, and complementary math and phenomenological models, as a pressure drop and catalyst deactivation. Model validation is developed, comparing reference results and the results by running the algorithm in MATLAB using a reference SYNGAS composition. Also, the constructed model considers a catalyst deactivation by sintering and pressure drop along the reactor. Several parameters were evaluated to identify the pro conditions for methyl alcohol production; these parameters include the gasifying agent selection, the biomass and steam ratio effect, and the biomass origin.

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Treatment of Urea Waste Water over Coconut Shell Activated Carbon Tethered Urease

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.1359 ◽

2013 ◽

Vol 295-298 ◽

pp. 1359-1363

Author(s):

Lei Wang ◽

Sha Wang ◽

Di Xiong ◽

Chun Rong Xiong

Keyword(s):

Waste Water ◽

Activated Carbon ◽

Packed Bed ◽

Catalytic Performance ◽

Relative Activity ◽

Packed Bed Reactor ◽

Coconut Shell ◽

Temperature Range ◽

Ph Range ◽

Coconut Shell Activated Carbon

Urease was successfully tethered onto coconut shell activated carbon (AC) granules. Degradation of urea was carried out in packed bed over the tethered urease. For 75% of retained activity, the tethered urease shows a broader temperature range of 42~80°C, compared to 45~75°C for the free enzyme. Similarly, the tethered urease has an increased resistance against the changes of pH. For a relative activity of 80%, the free urease had a pH range of 6.2-7.4, while it was 6.5–8.0 for the tethered urease. The Km values of the free and tethered ureases were 22.60 mg/mL and 7.43 mg/mL, respectively. And the Vm values were actually very close (~23.5 mg/min ) for both the tethered and free ureases. The catalytic performance of the tethered urease was tested in a packed bed reactor. The relative activity was maintained over 80% after 50 h of running in degradation of urea.

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Effects of Desilication in NaOH/Piperidine Medium and Phosphorus Modification on the Catalytic Activity of HZSM-5 Catalyst in Methanol to Propylene Conversion

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666200714002844 ◽

2020 ◽

Vol 23 ◽

Author(s):

Ebrahim Safaei ◽

Majid Taghizadeh

Keyword(s):

Catalytic Activity ◽

Catalytic Efficiency ◽

Ammonium Hydroxide ◽

Packed Bed ◽

Alkaline Treatment ◽

Packed Bed Reactor ◽

Molar Ratio ◽

Propylene Conversion ◽

Ft Ir ◽

Phosphorus Modification

Aims & Objective: H-ZSM-5 catalysts with a Si/Al molar ratio of 200 were effectively prepared by a microwaveassisted hydrothermal technique through the existence of tetrapropyl ammonium hydroxide (TPAOH). Methods: The introduction of controllable mesopores into ZSM-5 crystals was performed efficiently via desilication derived from an alkaline NaOH/piperidine solution. Then, the acidic characteristic of the desilicated ZSM-5 specimens was improved using phosphorus modification. The catalysts were subjected to XRD, ICP-OES, BET, FE-SEM, TGA, NH3-TPD and FT-IR analysis. The catalytic activity of the synthesized zeolites in the reaction of methanol to propylene (MTP) was examined in a packed-bed reactor at 475 °C, atmospheric pressure and WHSV of 0.9 h–1. Results & Conclusion: The findings showed alkaline treatment in NaOH/piperidine solution created uniform mesoporosity with no severe damage in the crystal structure. Similarly, phosphorus modification developed the acidic features and led to the optimal catalytic efficiency in terms of maximum propylene selectivity (49.16%) and propylene/ethylene (P/E) ratio (5.97) as well as the maximum lifetime of the catalyst.

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Thermal Behaviour of Candesartan Active substance and in pharmaceutical compounds

Revista de Chimie ◽

10.37358/rc.17.8.5787 ◽

2017 ◽

Vol 68 (8) ◽

pp. 1895-1902

Author(s):

Ioana Cristina Tita ◽

Eleonora Marian ◽

Bogdan Tita ◽

Claudia Crina Toma ◽

Laura Vicas

Keyword(s):

Thermal Behaviour ◽

Active Substance ◽

Pharmaceutical Research ◽

Pharmaceutical Product ◽

Nitrogen Atmosphere ◽

Pure Substance ◽

Scanning Calorimetry ◽

X Ray ◽

Ft Ir

Thermal analysis is one of the most frequently used instrumental techniques in the pharmaceutical research, for the thermal characterization of different materials from solids to semi-solids, which are of pharmaceutical relevance. In this paper, simultaneous thermogravimetry/derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) were used for characterization of the thermal behaviour of candesartan cilexetil � active substance (C-AS) under dynamic nitrogen atmosphere and nonisothermal conditions, in comparison with pharmaceutical product containing the corresponding active substance. It was observed that the commercial samples showed a different thermal profile than the standard sample, caused by the presence of excipients in the pharmaceutical product and to possible interaction of these with the active substance. The Fourier transformed infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRPD) were used as complementary techniques adequately implement and assist in interpretation of the thermal results. The main conclusion of this comparative study was that the TG/DTG and DSC curves, together with the FT-IR spectra, respectively X-ray difractograms constitute believe data for the discrimination between the pure substance and pharmaceutical forms.

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