Arrhenius Kinetic Analysis during Combustion of Spirulina platensis Microalgae

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.

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

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.851.137 ◽

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.

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An Investigation into the Combustion of Mixed Fuel Consisting of Bituminous Coal and Crude Bio-Oil

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.773-774.1184 ◽

2015 ◽

Vol 773-774 ◽

pp. 1184-1188

Author(s):

Hazlin Hamdan ◽

Munawar Zaman Shahruddin ◽

Ahmad Rafizan Mohamad Daud ◽

Syed Shatir A. Syed-Hassan

Keyword(s):

Gas Flow ◽

Bituminous Coal ◽

Decomposition Reaction ◽

Volatile Matter ◽

Kinetic Evaluation ◽

Exponential Factor ◽

Air Atmosphere ◽

Coal Fuel ◽

Bio Oil ◽

Lower Temperature

The combustion of bituminous coal, bio-oil, and their slurry mixtures were performed under air atmosphere using Thermogravimetric Analyzer (TGA). All samples were run from room temperature to 110°C and held for 10 minutes before the temperature was ramped to 1100°C and held again for 10 minutes at 1100°C at the heating rate of 10°C/min and gas flow rate of 50mL/min. Kinetic evaluation was conducted using a simple Arrhenius-type kinetic model with first-order decomposition reaction. Apparent activation energy, Ea, and pre-exponential factor, A, were calculated from the modelling equation. Results reveal that the reactivity of CBS fuel is higher than a single coal fuel to which the addition of bio-oil helps to increase the combustion performance of the blends. The optimum fuel ratio appears at 50:50 ratio with equal contribution of coal and bio-oil properties that contribute to the increase in volatile matter causing maximum combustion rate achievable at much lower temperature compared to single coal fuel.

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ANTIOXIDANT ACTIVITY OF SELECTED FORMULA Spirulina platensis TROCHES BASED ON PYSICAL CHARACTERISTICS

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v6i2.9019 ◽

2015 ◽

Vol 6 (2) ◽

Author(s):

Ria Fahleny ◽

Wini Trilaksani ◽

Iriani Setyaningsih

Keyword(s):

Antioxidant Activity ◽

Spirulina Platensis ◽

Physical Characteristics ◽

Bioactive Components ◽

Corn Flour ◽

Health Ministry ◽

Disintegration Time ◽

Second Stage ◽

Third Stage ◽

Three Stages

ABSTRACT Spirulina contains complete nutrition and bioactive components as a source of antioxidants. The aims of this research were to determine a formula of troche from Spirulina platensis according to the physical characteristic standard of the Indonesian Health Ministry, and to determine the antioxidant activity of the selected troche from Spirulina platensis. This research was conducted in three stages. The first stage was troches formulation. The second stage was troches physical analyses, including weight uniformity, friability, hardnes, and disintegration time. The third stage was to determine the antioxidant activity of the selected formula of troche from Spirulina platensis. There were five formulas of troches i.e., FTS 1, FTS 2, FTS 3, FTS 4, and FTS 5. The troche consisted of Spirulina platensis powder, carrageenan, gelatin, corn flour, sugarleaf, and mint powder. Based on the weight uniformity of the troche, all formulas met the standard. However, according to friability aspect, the best formula was FTS 1 with rate of 1.7%. The hardness of five formula ranged from 0.65 to 2.3 Kp, and none met the standard. The best formula based on disintegration time measurement was FTS 1 (24:47 minutes). Based on the physical characteristics of the troches, the selected formula was FTS 1. The antioxidant activity (IC50 of the selected formula (FTS 1) was 288,68 ppm. Keywords: antioxidant, troches, physical characteristics of troches, Spirulina platensis

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

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.851.149 ◽

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.

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ANTIOXIDANT ACTIVITY OF SELECTED FORMULA Spirulina platensis TROCHES BASED ON PYSICAL CHARACTERISTICS

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.28930/jitkt.v6i2.9019 ◽

2015 ◽

Vol 6 (2) ◽

Author(s):

Ria Fahleny ◽

Wini Trilaksani ◽

Iriani Setyaningsih

Keyword(s):

Antioxidant Activity ◽

Spirulina Platensis ◽

Bioactive Components ◽

Corn Flour ◽

Health Ministry ◽

Disintegration Time ◽

Second Stage ◽

The Third ◽

Third Stage ◽

Three Stages

ABSTRACT Spirulina contains complete nutrition and bioactive components as a source of antioxidants. The aims of this research were to determine a formula of troche from Spirulina platensis according to the physical characteristic standard of the Indonesian Health Ministry, and to determine the antioxidant activity of the selected troche from Spirulina platensis. This research was conducted in three stages. The first stage was troches formulation. The second stage was troches physical analyses, including weight uniformity, friability, hardnes, and disintegration time. The third stage was to determine the antioxidant activity of the selected formula of troche from Spirulina platensis. There were five formulas of troches i.e., FTS 1, FTS 2, FTS 3, FTS 4, and FTS 5. The troche consisted of Spirulina platensis powder, carrageenan, gelatin, corn flour, sugarleaf, and mint powder. Based on the weight uniformity of the troche, all formulas met the standard. However, according to friability aspect, the best formula was FTS 1 with rate of 1.7%. The hardness of five formula ranged from 0.65 to 2.3 Kp, and none met the standard. The best formula based on disintegration time measurement was FTS 1 (24:47 minutes). Based on the physical characteristics of the troches, the selected formula was FTS 1. The antioxidant activity (IC50 of the selected formula (FTS 1) was 288,68 ppm. Keywords: antioxidant, troches, physical characteristics of troches, Spirulina platensis

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Investigation of pyrolysis kinetics parameters and thermal behavior of thermochemically modified bagasse for bioenergy potential

SN Applied Sciences ◽

10.1007/s42452-021-04345-6 ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Christiano Bruneli Peres ◽

André Henrique Rosa ◽

Leandro Cardoso de Morais

Keyword(s):

Sugarcane Bagasse ◽

Volatile Matter ◽

Pyrolysis Kinetics ◽

Heating Rates ◽

Kinetics Parameters ◽

Exponential Factor ◽

Other Substances ◽

Textural Parameters ◽

Three Stages ◽

Morphological Differences

AbstractBiomass is considering a source of organic carbon, which can replace fossil resources by using pyrolysis process, therefore an efficient biomass thermal modification technology has been target of so much research. The objective of this work is to study the potential energy of sugarcane bagasse and thermochemically modified bagasse for bioenergy potential for use in heat generation and energy. The thermal analysis was conducted by powder-shaped exposure of the three study samples (SB, AC-1, and AC-2) at three heating rates of (5, 7.5 and 10 °C min−1), it was possible to identify three stages of thermal degradation and study some thermochemical reactions, using two iso-conversional models, Kissinger–Akahira–Sunose (KAS) and Ozawa–Flynn–Wall (OFW) to calculate some kinetic parameters, such as activation energy (Ea) and pre-exponential factor (A). First step was about the devolatilization of volatile matter, moisture, and other substances. Degradation of hemicellulose, cellulose and lignin were shown in a second step. Characterization analyzes, such as SEM–EDX and textural parameters of the samples, show the presence of carbon in samples SB and AC-1. Due to SEM analyzes, morphological differences between the samples are showing as AC-1 and AC-2 samples present a rougher shape with pores, on the other hand, SB sample show a fibrous shape. In conclusion, sugarcane bagasse and thermochemically modified bagasse, show very promising results, for future studies, such as for bioenergy potential.

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Characterization on Physical and Thermal Behavior of Torrefied Biochar from Oil Palm Empty Fruit Bunch

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.l1129.10812s219 ◽

2019 ◽

Vol 8 (12S2) ◽

pp. 747-752

Keyword(s):

Thermal Behavior ◽

Oil Palm ◽

Renewable Energy Sources ◽

Calorific Value ◽

Volatile Matter ◽

Empty Fruit Bunch ◽

Second Stage ◽

Third Stage ◽

Three Stages ◽

Holding Temperature

This study was aimed to determine the physical properties including physical appearance, mass yield, proximate besides calorific value and thermal behavior of torrefied oil palm empty fruit bunch (OPEFB) biochar as an alternative renewable energy sources. The influence of three major torrefaction parameters namely particle size, holding temperature and residence time on them were investigated. The thermal behavior of torrefied OPEFB biochar has been identified using TGA-DSC. The degradation is divided into three stages which are dehydration, devolatilizations and decomposition of char. During the dehydration, the moisture and water content was removed and during second stage, the volatile matter was removed along with the removal of hemicellulose, cellulose and lignin while on the third stage shows the decompositions of biochar to completely degrade.

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Kinetic analysis of co-combustion of microalgae spirulina platensis and synthetic waste through the fitting model

MATEC Web of Conferences ◽

10.1051/matecconf/201820400009 ◽

2018 ◽

Vol 204 ◽

pp. 00009 ◽

Cited By ~ 1

Author(s):

Sukarni Sukarni ◽

Ardianto Prasetiyo ◽

Sumarli Sumarli ◽

Imam Muda Nauri ◽

Avita Ayu Permanasari

Keyword(s):

Activation Energy ◽

Thermal Degradation ◽

Kinetic Analysis ◽

Heating Rate ◽

Spirulina Platensis ◽

Thermogravimetric Analyzer ◽

Second Stage ◽

Air Atmosphere ◽

Three Stages ◽

Fitting Model

Thermogravimetric analyzer had been occupied to investigate the behavior of co-combustion between microalgae Spirulina platensis and synthetic waste. The powder of microalgae and synthetic waste were mixed in the same ratio of 50/50. Around 10 mg of the sample was heated up in the chamber under air atmosphere flowrate of 100 ml/min at a heating rate of 10 °C/min. The results showed that the sample blend is undergoing thermal degradation in the three stages. The most massive reaction occurred in the second stage in which around 74% of the mass degraded and combusted. The activation energy in the main combustion reaction zone according to the method of Horowitz–Metzger was 57.77 kJ/mol.

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The Coherence of Mary Barton: Romance, Realism, and Utopia

Victoriographies ◽

10.3366/vic.2015.0194 ◽

2015 ◽

Vol 5 (3) ◽

pp. 185-200

Author(s):

Robert Z. Birdwell

Keyword(s):

Thomas Carlyle ◽

The Novel ◽

Second Stage ◽

The Third ◽

Third Stage ◽

Three Stages ◽

Mode Of Production

Critics have argued that Elizabeth Gaskell's first novel, Mary Barton (1848), is split by a conflict between the modes of realism and romance. But the conflict does not render the novel incoherent, because Gaskell surpasses both modes through a utopian narrative that breaks with the conflict of form and gives coherence to the whole novel. Gaskell not only depicts what Thomas Carlyle called the ‘Condition of England’ in her work but also develops, through three stages, the utopia that will redeem this condition. The first stage is romantic nostalgia, a backward glance at Eden from the countryside surrounding Manchester. The second stage occurs in Manchester, as Gaskell mixes romance with a realistic mode, tracing a utopian drive toward death. The third stage is the utopian break with romantic and realistic accounts of the Condition of England and with the inadequate preceding conceptions of utopia. This third stage transforms narrative modes and figures a new mode of production.

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The Subject Matter of Intellectual Property

10.1093/oso/9780199688616.001.0001 ◽

2017 ◽

Author(s):

Justine Pila

Keyword(s):

Intellectual Property ◽

Subject Matter ◽

Final Stage ◽

Theoretical Framework ◽

Trade Mark ◽

Second Stage ◽

Essential Properties ◽

The Subject ◽

Three Stages ◽

The Relationship

This book offers a study of the subject matter protected by each of the main intellectual property (IP) regimes. With a focus on European and UK law particularly, it considers the meaning of the terms used to denote the objects to which IP rights attach, such as ‘invention’, ‘authorial work’, ‘trade mark’, and ‘design’, with reference to the practice of legal officials and the nature of those objects specifically. To that end it proceeds in three stages. At the first stage, in Chapter 2, the nature, aims, and values of IP rights and systems are considered. As historically and currently conceived, IP rights are limited (and generally transferable) exclusionary rights that attach to certain intellectual creations, broadly conceived, and that serve a range of instrumentalist and deontological ends. At the second stage, in Chapter 3, a theoretical framework for thinking about IP subject matter is proposed with the assistance of certain devices from philosophy. That framework supports a paradigmatic conception of the objects protected by IP rights as artifact types distinguished by their properties and categorized accordingly. From this framework, four questions are derived concerning: the nature of the (categories of) subject matter denoted by the terms ‘invention’, ‘authorial work’, ‘trade mark’, ‘design’ etc, including their essential properties; the means by which each subject matter is individuated within the relevant IP regime; the relationship between each subject matter and its concrete instances; and the manner in which the existence of a subject matter and its concrete instances is known. That leaves the book’s final stage, in Chapters 3 to 7. Here legal officials’ use of the terms above, and understanding of the objects that they denote, are studied, and the results presented as answers to the four questions identified previously.

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