scholarly journals Pyrolysis Reaction Kinetics of Styrofoam Plastic Waste

2021 ◽  
Vol 9 (1) ◽  
pp. 57-62
Author(s):  
Feybi A. G. Kauwo ◽  
I Dewa K. Anom ◽  
John Z. Lombok

Pyrolysis at the temperature range of 170 °C-237 °C against polystyrene (Styrofoam) type plastic waste is carried out without a catalyst and added a catalyst. The purpose of this research was to study the reaction kinetics of Styrofoam pyrolysis to liquid smoke products. Pyrolysis using a series of tools made of glass to observe the processes that occur in the reactor. The results showed that Styrofoam pyrolysis for liquid smoke products without catalyst and added catalyst took place in the first-order reaction. The kinetics of the pyrolysis reaction without a catalyst to observe the formation of liquid smoke products obtained by the equation of the reaction constant following the Arrhenius equation k = Ae2111.4 / T, with an activation energy value (Ea) of 17.554 x 103 kJ/mol and pyrolysis using a catalyst obtained k = Ae10330/T, with an activation energy value (Ea) of 85.883x103 kJ/mol. Using catalysts during pyrolysis will reduce the temperature so that the reaction will be slow.

2017 ◽  
Vol 35 (No. 4) ◽  
pp. 360-366 ◽  
Author(s):  
Pavlović Aleksandra N ◽  
Mrmošanin Jelena M ◽  
Krstić Jovana N ◽  
Mitić Snežana S ◽  
Tošić Snežana B ◽  
...  

The storage stability of catechins, procyanidins, and total flavonoids in dark chocolate was investigated. The obtained results showed that the degradation of flavonoids followed first-order reaction kinetics. Temperature-dependent degradation was modelled on the Arrhenius equation. The activation energy for the degradation of dark chocolate flavonoids during storage was 61.2 kJ/mol. During storage, flavonoids degraded more rapidly at 35°C (k = 7.8 × 10<sup>–3</sup>/day) than at 22°C (k = 5.4 × 10<sup>–3</sup>/day) and 4°C (k = 2.2 × 10<sup>–3</sup>/day).


2021 ◽  
Vol 4 (2) ◽  
pp. 135-140
Author(s):  
I Dewe Ketut Anom

This research aims to study the reaction kinetics of gas formation in the pyrolysis of styrofoam waste. Pyrolysis of styrofoam waste without a catalyst takes place at a constant temperature of 180°C. In contrast, the pyrolysis of styrofoam waste by adding a zeolite catalyst took place at a constant temperature of 170°C. The amount of styrofoam waste used in this research sample is 200 grams, and the natural zeolite catalyst is 5 grams. Pyrolysis of styrofoam waste without using a catalyst form a gas at a constant temperature of 180°C, the kinetics of the reaction takes place on the zero-order. This result follows the Arrhenius equation K = Ae10617/RT with an activation energy value (Ea) of 1.27x103 kJ.mol-1. Pyrolysis of styrofoam waste by adding a zeolite catalyst to gas formation at a constant temperature of 170°C also takes place on the zero-order. The equation follows Arrhenius K= Ae4711,5/RT and the activation energy value (Ea) is 5.66x102 kJ.mol-1.


1960 ◽  
Vol 33 (2) ◽  
pp. 335-341
Author(s):  
Walter Scheele ◽  
Karl-Heinz Hillmer

Abstract As a complement to earlier investigations, and in order to examine more closely the connection between the chemical kinetics and the changes with vulcanization time of the physical properties in the case of vulcanization reactions, we used thiuram vulcanizations as an example, and concerned ourselves with the dependence of stress values (moduli) at different degrees of elongation and different vulcanization temperatures. We found: 1. Stress values attain a limiting value, dependent on the degree of elongation, but independent of the vulcanization temperature at constant elongation. 2. The rise in stress values with the vulcanization time is characterized by an initial delay, which, however, is practically nonexistent at higher temperatures. 3. The kinetics of the increase in stress values with vulcanization time are both qualitatively and quantitatively in accord with the dependence of the reciprocal equilibrium swelling on the vulcanization time; both processes, after a retardation, go according to the first order law and at the same rate. 4. From the temperature dependence of the rate constants of reciprocal equilibrium swelling, as well as of the increase in stress, an activation energy of 22 kcal/mole can be calculated, in good agreement with the activation energy of dithiocarbamate formation in thiuram vulcanizations.


Author(s):  
Adnan Bozdoğan ◽  
Kurban Yaşar

This research was performed to elucidate the effects of temperature on the degradation kinetics of anthocyanins in shalgam beverage. Shalgam beverage was produced according to traditional production method. Then, it was kept at three different temperatures (65°C, 75°C, and 85°C) for 12 hours, and the relevant quantities of anthocyanins were determined thereafter. The research revealed that degradation of the anthocyanins was well described with a 1st-order reaction kinetics model and the R2 values varied in the range of 0.9059-0.9715. Activation energy of the reaction was determined to be 48537 Joule/mole. The half-lives of anthocyanins at 65°C and 75° C, and 85°C were found to be 138.63, 136.72, and 51.57, respectively. Compared the half-life periods at different temperatures, anthocyanins were found to be more resistant at 65°C and 75°C than at 85°C.


2017 ◽  
Vol 23 (4) ◽  
pp. 495-506 ◽  
Author(s):  
Larissa Falleiros ◽  
Bruna Cabral ◽  
Janaína Fischer ◽  
Carla Guidini ◽  
Vicelma Cardoso ◽  
...  

The immobilization and stabilization of Aspergillus oryzae ?-galactosidase on Duolite??A568 was achieved using a combination of physical adsorption, incubation step in buffer at pH 9.0 and cross-linking with glutaraldehyde and in this sequence promoted a 44% increase in enzymatic activity as compared with the biocatalyst obtained after a two-step immobilization process (adsorption and cross-linking). The stability of the biocatalyst obtained by three-step immobilization process (adsorption, incubation in buffer at pH 9.0 and cross-linking) was higher than that obtained by two-steps (adsorption and cross-linking) and for free enzyme in relation to pH, storage and reusability. The immobilized biocatalyst was characterized with respect to thermal stability in the range 55-65 ?C. The kinetics of thermal deactivation was well described by the first-order model, which resulted in the immobilized biocatalyst activation energy of thermal deactivation of 71.03 kcal/mol and 5.48 h half-life at 55.0 ?C.


2012 ◽  
Vol 581-582 ◽  
pp. 694-697
Author(s):  
Yong Yao ◽  
De Li Luo ◽  
Zhi Yong Huang ◽  
Jiang Feng Song

In order to evaluate the feasibility of tritium recovery from tritiated water by thermochemical decomposition using ZrNi5, the kinetics of reaction between ZrNi5 and water vapor was studied by thermogravimetric method in the temperature range from 673K to 823K. The result shows that reaction rate increased significantly with the increasing of temperature and H2O concentration; the reaction mechanism for ZrNi5 can be described by the first-order chemical reaction, and the reaction is first order for H2O concentration. The reaction activation energy of ZrNi5 is 55.8kJ/mol calculated from the Arrhenius equation.


2001 ◽  
Vol 36 (3) ◽  
pp. 589-604 ◽  
Author(s):  
Julian M. Dust ◽  
Christopher S. Warren

Abstract The kinetics of the alkaline rearrangement of O,O-dimethyl-(2,2,2-trichloro-1- hydroxyethyl)phosphonate, (trichlorfon, 1), the active insecticidal component in such formulations as Dylox, was followed at 25±0.5°C by high pressure liquid chromatography (UV-vis detector, 210 nm). The rearrangement product, O,Odimethyl- O-(2,2-dichloroethenyl)phosphate (dichlorovos, 2), which is a more potent biocide than trichlorfon, undergoes further reaction, and the kinetics, consequently, cannot be treated by a standard pseudo-first-order plot. A two-point van't Hoff (initial rates) method was used to obtain pseudo-first-order rate constants (kѱ) at 25, 35 and 45°C: 2.6 × 10-6, 7.4 × 10-6 and 2.5 × 10-5 s-1, respectively. Arrhenius treatment of this data gave an activation energy (Ea) of 88 kJ·mol-1 with a pre-exponential factor (A) of 5.5 × 109 s-1. Kinetic trials at pH 8.0 using phosphate and tris buffer systems show no buffer catalysis in this reaction and indicate that the rearrangement is subject to specific base catalysis. Estimates are reported for pseudo-first-order half-lives for trichlorfon at pH 8.0 for environmental conditions in aqueous systems in the Corner Brook region of western Newfoundland, part of the site of a recent trichlorfon aerial spray program.


1950 ◽  
Vol 28b (7) ◽  
pp. 358-372
Author(s):  
Cyrias Ouellet ◽  
Adrien E. Léger

The kinetics of the polymerization of acetylene to cuprene on a copper catalyst between 200° and 300 °C. have been studied manometrically in a static system. The maximum velocity of the autocatalytic reaction shows a first-order dependence upon acetylene pressure. The reaction is retarded in the presence of small amounts of oxygen but accelerated by preoxidation of the catalyst. The apparent activation energy, of about 10 kcal. per mole for cuprene growth between 210° and 280 °C., changes to about 40 kcal. per mole above 280 °C. at which temperature a second reaction seems to set in. Hydrogen, carbon monoxide, or nitric oxide has no effect on the reaction velocity. Series of five successive seedings have been obtained with cuprene originally grown on cuprite, and show an effect of aging of the cuprene.


2013 ◽  
Vol 830 ◽  
pp. 278-281
Author(s):  
Zhi Yuan Sun ◽  
Wei Wei Geng ◽  
Shou Zhi Pu

A new photochromic diarylethene compound 1-(2-cyan-3-phenyl)-2-[5-(4-cyanobenzene) -2-methyl-3-thienyl] perfluorocyclopentene was synthesized. And their properties inculding photochromis, fluorescence in both hexane and solid films, reaction kinetics of cyclization and cycloreversion were studied. And its absorption maxima were observed at 539 nm in hexane and at 552 nm in PMMA films, respectively, upon irradiation with 313 nm UV light. The fluorescence intensity of diarylethene decreased upon irradiation with 313 nm UV light. Besides, the cyclization and cycloreversion processes of the compound were determined to be the zeroth and first order reaction by UV-Vis spectra, respectively.


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