Thermal Characteristic of Tetraselmis chuii Combustion Influenced by Titanium Dioxide (TiO2) Nanoparticle

2020 ◽  
Vol 851 ◽  
pp. 149-155
Author(s):  
Sukarni Sukarni ◽  
Ardianto Prasetiyo ◽  
Retno Wulandari ◽  
Aloon Eko Widiono ◽  
Poppy Puspitasari
Keyword(s):  
Titanium Dioxide ◽  
Reaction Order ◽  
Thermal Characteristic ◽  
Combustion Process ◽  
Differential Method ◽  
Exponential Factor ◽  
Atmospheric Air ◽  
Central Java ◽  
Tetraselmis Chuii ◽  
Factor Log

The investigation of Titanium dioxide (TiO2) nanoparticles on the thermal characteristic of Tetraselmis chuii (T.Chuii) microalgae during combustion process has been carried out through a thermogravimetric (TG) analyzer. T.Chuii microalgae samples were cultured within 8 days at BBPBAP Jepara, Central Java, Indonesia. The microalgae sediment was dried at 80°C for 24 hours then was powdered by means of a mortar. Thereafter, the dried powder of microalgae was filtered with a size of 60 mesh. Titanium dioxide (TiO2) nanoparticles were used as catalysts with the particle size of < 25 nm; these were obtained from Singapore’s Sigma Aldrich. Amount of 0.03 mg of TiO2 and 10 mg of T.Chuii microalgae were mixed mechanically using a mortar to guarantee the homogeneous blend, and then this sample was heated up in the oven for 14 hours at 80°C. The TG experiment was performed at a temperature range 25 to 900°C with atmospheric air at a flow rate of 50 mL/min and a heating rate of 15 °C/min. Differential method of Arrhenius is applied to evaluate kinetic parameters, including reaction order (n), activation energy (Ea), and pre-exponential factor (log A) that were 0.9; 74,191 kJ/mol and 6.38 min-1 for the stage II and 0.87; 118.47 kJ/mol and 7.29 min-1 for stage V.

Arrhenius Kinetic Analysis during Combustion of Spirulina platensis Microalgae

2020 ◽  
Vol 851 ◽  
pp. 142-148
Author(s):  
Sukarni Sukarni ◽  
Muklisul Anwar
Keyword(s):  
Spirulina Platensis ◽  
Volatile Matter ◽  
Differential Method ◽  
Air Flow Rate ◽  
Kinetic Evaluation ◽  
Exponential Factor ◽  
Kinetic And Thermodynamic Parameters ◽  
Second Stage ◽  
Factor Log ◽  
Three Stages

Characteristics and potential of microalgae Spirulina platensis as an energy source were studied in regard to the decomposition patterns, as well as kinetic and thermodynamic parameters. The thermogravimetric analysis was performed using the TGA instrument (Mettler Toledo TG DSC 1) at a heating rate of 30 °C/min, with an atmospheric air flow-rate of 100 ml/min at the temperature range of 25-1000 °C. The kinetic was evaluated using a differential method of Arrhenius. The results showed that Spirulina platensis microalgae decomposed into three stages. The first stage is related to the evaporation of moisture, the second stage is associated with the release of volatile matter, and the final stage is the combustion stage of char. The kinetic evaluation resulted in the respective activation energy (), pre-exponential factor (log A) and reaction order (n) are 53.57 kJ/mol, 4.4 min-1, and 1.73. It also understands from the thermodynamic analysis that the respective values of enthalpy (), Gibbs free energy ( and the entropies ( were 48.50 kJ/mol, 146,73 kJ/mol, and-174,78 J/mol.

Pyrolytic Characteristics and Kinetic Parameters Evaluation of Cassava Stalks Using Thermogravimetric Analyzer

2020 ◽  
Vol 851 ◽  
pp. 137-141
Author(s):  
Sukarni Sukarni ◽  
M. Rifqi Ramadhan
Keyword(s):  
Reaction Order ◽  
Frequency Factor ◽  
Differential Method ◽  
Nitrogen Flow ◽  
Nitrogen Flow Rate ◽  
Kinetic Evaluation ◽  
Thermogravimetric Analyzer ◽  
Second Stage ◽  
Factor Log ◽  
Kinetics Of

Pyrolytic characteristics and kinetics of cassava stalks as a renewable energy source were delved via a thermogravimetric (TG) analyzer. About 10 mg powder of the sample was heated up in the TG cavity under inert conditions with 50 ml.min-1 nitrogen flow rate and operated at 20 °C min-1 of heating program. The pyrolysis process of cassava stalks was taken place into three main stages, in which the peak reaction occurred at the second stage with 70% of the mass was degraded. The differential method of Arrhenius kinetic evaluation resulted in the values of reaction order (n) that was 0.99, activation energy that was 89.46 kJ/mol and logarithmic frequency factor (log A) was 7.7 min-1.

Thermogravimetric Study on the Thermal Characteristics of Tetraselmis chuii Microalgae Pyrolysis in the Presence of Titanium dioxide

2020 ◽  
Vol 851 ◽  
pp. 156-163
Author(s):  
Sukarni Sukarni ◽  
Aloon Eko Widiono ◽  
Retno Wulandari ◽  
Ardianto Prasetiyo ◽  
Poppy Puspitasari
Keyword(s):  
Activation Energy ◽  
Titanium Dioxide ◽  
Thermal Characteristic ◽  
Thermal Characteristics ◽  
Mass Ratio ◽  
Second Stage ◽  
Tetraselmis Chuii ◽  
Thermal Analyzer ◽  
Third Stage ◽  
Blended Fuel

This study aims to analyze the thermal characteristics of Tetraselmis chuii (T.Chuii) microalgae in the presence of TiO2 (Titanium dioxide). The experiment was carried out on thermal analyzer equipment under inert condition. The blended sample has a mass ratio of microalgae and TiO2 that was 10:0.03 (wt%). The results of the thermal analysis show that the addition of TiO2 can change the temperature characteristics during the reaction process. The Coats-Redfern method is applied to calculate activation energy (Ea) resulted in the value of the blended fuel in the second stage that was 56.9 kJ/mol lower than that of pure microalgae that was 70.68 kJ/mol and conversely in the third stage the value of activation energy for blended fuel was 264.57 kJ/mol higher than pure microalgae that was 223.25 kJ/mol. Overall results pointed out that TiO2 had a significant impact on the thermal characteristic of Tetraselmis chuii during the pyrolysis process.

scholarly journals Isothermal Kinetic Analysis of the Thermal Decomposition of Wood Chips from an Apple Tree

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 195
Author(s):  
Ivan Vitázek ◽  
Martin Šotnar ◽  
Stella Hrehová ◽  
Kristína Darnadyová ◽  
Jan Mareček
Keyword(s):  
Thermal Decomposition ◽  
Apple Tree ◽  
Combustion Process ◽  
Reaction Model ◽  
Wood Chips ◽  
Small Scale ◽  
Exponential Factor ◽  
Air Atmosphere ◽  
First Order Chemical Reaction ◽  
Isothermal Kinetic

The thermal decomposition of wood chips from an apple tree is studied in a static air atmosphere under isothermal conditions. Based on the thermogravimetric analysis, the values of the apparent activation energy and pre-exponential factor are 34 ± 3 kJ mol−1 and 391 ± 2 min−1, respectively. These results have also shown that this process can be described by the rate of the first-order chemical reaction. This reaction model is valid only for a temperature range of 250–290 °C, mainly due to the lignin decomposition. The obtained results are used for kinetic prediction, which is compared with the measurement. The results show that the reaction is slower at higher values of degree of conversion, which is caused by the influence of the experimental condition. Nevertheless, the obtained kinetic parameters could be used for the optimization of the combustion process of wood chips in small-scale biomass boilers.

Mechanisms and kinetics of initial pyrolysis and combustion reactions of 1,1-diamino-2,2-dinitroethylene from density functional tight-binding molecular dynamics simulations

2019 ◽  
Vol 97 (11) ◽  
pp. 795-804 ◽  
Author(s):  
Dong Xiang ◽  
Weihua Zhu
Keyword(s):  
Activation Energy ◽  
Molecular Dynamics ◽  
Density Functional ◽  
Tight Binding ◽  
Combustion Process ◽  
Exponential Factor ◽  
Three Stages ◽  
Dynamics Simulations ◽  
Combustion Processes ◽  
Kinetics Of

The density functional tight-binding molecular dynamics approach was used to study the mechanisms and kinetics of initial pyrolysis and combustion reactions of isolated and multi-molecular FOX-7. Based on the thermal cleavage of bridge bonds, the pyrolysis process of FOX-7 can be divided into three stages. However, the combustion process can be divided into five decomposition stages, which is much more complex than the pyrolysis reactions. The vibrations in the mean temperature contain nodes signifying the formation of new products and thereby the transitions between the various stages in the pyrolysis and combustion processes. Activation energy and pre-exponential factor for the pyrolysis and combustion reactions of FOX-7 were obtained from the kinetic analysis. It is found that the activation energy of its pyrolysis and combustion reactions are very low, making both take place fast. Our simulations provide the first atomic-level look at the full dynamics of the complicated pyrolysis and combustion process of FOX-7.

scholarly journals A kinetic evaluation on no2 formation in the post-flame region of pressurized oxy-combustion process

2020 ◽  
pp. 236-236
Author(s):  
Xuebin Wang ◽  
Gaofeng Dai ◽  
Gregory Yablonsk ◽  
Milan Vujanovic ◽  
Richard Axelbaum
Keyword(s):  
Power Plants ◽  
Combustion Process ◽  
Strong Acid ◽  
Dew Point ◽  
Kinetic Evaluation ◽  
Atmospheric Air ◽  
Energy Penalty ◽  
Flame Region ◽  
No2 Formation ◽  
Time Required

Pressurized oxy-combustion is a promising technology that can significantly reduce the energy penalty associated with first generation oxy-combustion for CO2 capture in coal-fired power plants. However, higher pressure enhances the production of strong acid gases, including NO2 and SO3, aggravating the corrosion threat during flue gas recirculation. In the flame region, high temperature NOx exists mainly as NO, while conversion from NO to NO2 happened in post-flame region. In this study, the conversion of NO ? NO2 has been kinetically evaluated under representative post-flame conditions of pressurized oxy-combustion after validating the mechanism (80 species and 464 reactions), which includes nitrogen and sulfur chemistry based on GRI-Mech 3.0. The effects of residence time, temperature, pressure, major species (O2/H2O), and minor or trace species (CO/SOx) on NO2 formation are studied. The calculation results show that when pressure is increased from 1 to 15 bar, NO2 is increased from 1 to 60 ppm, and the acid dew point increases by over 80?C. Higher pressure and temperature greatly reduce the time required to reach equilibrium, e.g., at 15 bar and 1300?C, equilibrium is reached in 1 millisecond and the NO2/NO is about 0.8%. The formation and destruction of NO2 is generally through the reversible reactions: NO+O+M=NO2+M, HO2+NO=NO2+OH, and NO+O2=NO2+O. With increasing pressure and decreasing temperature, O plays a much more important role than HO2 in the oxidation of NO. A higher water vapor content accelerates NO2 formation in all cases by providing more O and HO2 radicals. The addition of CO or SO2 also promotes the formation of NO2. Finally, NO2 formation in a Pressurized oxy-combustion furnace is compared with that in a practical atmospheric air-combustion furnace and the comparison show that NO2 formation in a Pressurized oxy-combustion furnace can be over 10 times that of an atmospheric air-combustion furnace.

Thermal processing of sewage sludge by drying, pyrolysis, gasification and combustion

2001 ◽  
Vol 44 (10) ◽  
pp. 333-339 ◽  
Author(s):  
P. Stolarek ◽  
S. Ledakowicz
Keyword(s):  
Thermal Decomposition ◽  
Sewage Sludge ◽  
Kinetic Parameters ◽  
Thermal Processing ◽  
Combustion Process ◽  
Order Kinetic ◽  
Municipal Sludge ◽  
Pyrolysis Kinetics ◽  
Exponential Factor ◽  
First Order

Thermal processing of sewage sludge including drying, pyrolysis and gasification or combustion may be an alternative to other ways of utilising it. In this paper thermogravimetric analysis (TGA) was employed in the investigation of thermal decomposition of sewage sludge. The kinetic parameters of drying, pyrolysis and gasification or combustion of sewage sludge have been determined in an inert-gas (argon) and additionally some series of the sludge decomposition experiments have been carried out in air, in order to compare pyrolysis and combustion. The pyrolysis char has been gasified with carbon dioxide. A typical approach to the kinetics of thermal decomposition of a solid waste is to divide the volatile evolution into a few fractions (lumps), each of which is represented by a single first-order reaction. If these lumps are assumed to be non-interacting and evolved by independent parallel reactions the first-order kinetic parameters such as activation energy Ei and pre-exponential factor Ai can be determined from mathematical evaluation of TG or DTG curves. The object of our investigations was a municipal sludge from the two wastewater treatment plants (WTP) in Poland. The experiments have been carried out in the thermobalance Mettler-Toledo type TGA/SDTA851 LF, in the temperature range 30-1,000°C. Five different values of heating rate have been applied β = 2, 5, 10, 15 and 20 K/min. The values of Ei and Ai have been determined for all recognised lumps of gaseous products. The method employed has also revealed its usefulness for the determination of kinetic parameters for municipal sludge, that possess an undefined content. An alternative route to combustion of sewage sludge is its gasification, which significantly increases the gaseous product (pyrolytic gas + syngas). Besides pyrolysis kinetics, gasification or combustion process kinetics have also been determined.

scholarly journals Mapping of Marine Area Boundary of Central Java Province using Differential GPS Survey Method

2004 ◽  
Vol 16 (2) ◽  
Author(s):  
Nurul Khakhim ◽  
Dulbahri Dulbahri ◽  
Barandi Sapta Widartono
Keyword(s):  
Base Point ◽  
Base Station ◽  
Differential Method ◽  
Base Line ◽  
Differential Gps ◽  
Central Java ◽  
Gps Survey ◽  
Gps Measurement ◽  
Base Reference ◽  
Central Java Province

The development of GPS (Global Positioning System) technology which is measuring position by satellite, has taken a great metodology aspect of position on surface of earth. The standard GPS measurement takes an absolute positioning. To develop the accurate abd precision, it is used the differential method. Differential GPS measurement can be much more accurate than standard GPs measurement, wherever the method uses one receiver as base station/ reference and the other receiver as field station in a same time. That could reduce and eliminate drifts and errors. The aim of research is use the differential method of GPS survey to map the ocean boundary of Central Java Province. Physical data which neede are base line and base point. Base line were taken from obsrvation of longtime Landsat TM image band 5th based o opinion that shore line are clear seems and easy to interpreted at 10.00 am according to Landsat satellite reording time and the lowest tide time as base line. Location of lowest tide were selected at conspicuous place, such as cape, dry shore, etc and measured base on the BPN (Badan Pertahanan Nasional) base/ reference point (orde 2 and 3) on the district, with GPS differential metod. Twelve miles distance from base line of ocean bounddary is belong to province and 1/3 of is belong to district. Characteristic of marine landform as cape, bay, estuaria, attended to international rules. Final report of the research were 1) oean boundary map of Center Java Province, 2) the location and base/ reference points (orde 2 and 3) that could be reference as a base point differential method.

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