scholarly journals Determination of key-thermodynamic parameters using a kinetic modeling approach to describe the post-consumer poly(ethylene terephthalate) hydrolysis catalyzed by cutinase from Humicola insolens

2021 ◽  
Author(s):  
Erika de Queiros Eugenio ◽  
Ivone Sampaio Pereira Campisano ◽  
Aline Machado de Castro ◽  
Maria Alice Zarur Coelho ◽  
Marta Antunes Pereira Langone
Keyword(s):  
Kinetic Model ◽  
Thermodynamic Parameters ◽  
Ethylene Terephthalate ◽  
Activation Entropy ◽  
Arrhenius Law ◽  
Humicola Insolens ◽  
Poly Ethylene Terephthalate ◽  
Reliable Parameter ◽  
Poly Ethylene

Abstract The search for a straightforward technology for post-consumer poly(ethylene terephthalate) (PC-PET) degradation is essential to develop a circular economy. In this context, PET hydrolases such as cutinases can be used as bioplatforms for this purpose. Humicola insolens cutinase (HiC) is a promising biocatalyst for PC-PET hydrolysis. Therefore, this work evaluated a kinetic model, and it was observed that the HiC seems not to be inhibited by any of the main PET hydrolysis products such as terephthalic acid (TPA), mono-(2-hydroxyethyl) terephthalate (MHET), and bis-(2-hydroxyethyl) terephthalate (BHET). The excellent fitting of the experimental data to a kinetic model based on enzyme-limiting conditions validates its employment for describing the enzymatic PC-PET hydrolysis using two-particle size ranges (0.075-0.250, and 0.250-0.600 mm) and temperatures (40, 50, 55, 60, 70, and 80 ºC). The Arrhenius law provided a reliable parameter (activation energy of 98.9 ± 2.6 kJ mol −1 ) for enzymatic hydrolysis, which compares well with reported values for chemical PET hydrolysis. The thermodynamic parameters of PC-PET hydrolysis corresponded to activation enthalpy of 96.1 ± 3.6 kJ mol -1 and activation entropy of 10.8 ± 9.8 J mol -1 K -1 . Thus, the observed rate enhancement with temperature was attributed to the enthalpic contribution, and this understanding is helpful to the comprehension of enzymatic behavior on hydrolysis reaction.

Supercritical fluid extraction and chromatography for the determination of oligomers in poly(ethylene terephthalate) films

1991 ◽  
Vol 63 (20) ◽  
pp. 2371-2377 ◽  
Author(s):  
Keith D. Bartle ◽  
Terry. Boddington ◽  
Anthony A. Clifford ◽  
Nicholas J. Cotton ◽  
Christopher J. Dowle
Keyword(s):  
Supercritical Fluid Extraction ◽  
Supercritical Fluid ◽  
Ethylene Terephthalate ◽  
Fluid Extraction ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Determination of local mechanical stresses in dyed poly(ethylene terephthalate) by IR spectroscopy

1979 ◽  
Vol 30 (5) ◽  
pp. 686-688
Author(s):  
D. Saidov ◽  
Kh. Khabibulloev ◽  
R. M. Marupov ◽  
V. I. Dasturi ◽  
M. S. Umarova
Keyword(s):  
Ir Spectroscopy ◽  
Ethylene Terephthalate ◽  
Mechanical Stresses ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

scholarly journals Kinetic Studies on Saponification of Poly(ethylene terephthalate) Waste Powder Using Conductivity Measurements

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Dilip B. Patil ◽  
Vijendra Batra ◽  
Sushil B. Kapoor
Keyword(s):  
Thermodynamic Parameters ◽  
Kinetic Studies ◽  
Frequency Factor ◽  
Reaction Rates ◽  
Reaction Rate Constant ◽  
Activation Entropy ◽  
Constant Frequency ◽  
Free Energy Of Activation ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Conductometric measurement technique has been deployed to study the kinetic behavior during the reaction of poly(ethylene terepthalate) (PET) and NaOH. A laboratory made arrangement with facility of continuous stirring was used to carry out experiments at desired temperature. With conductometry, the determination of kinetic as well as thermodynamic parameters becomes more simple and faster as compared to gravimetry. Chemical kinetics of this reaction shows that it is a second order reaction with reaction rate constant 2.88×10-3 g−1 s−1 at 70°C. The specific reaction rates of the saponification reaction in the temperature range at various temperatures (50–80°C) were determined. From the data, thermodynamic parameters such as activation energy, Arrhenius constant (frequency factor), activation enthalpy, activation entropy, and free energy of activation obtained were 54.2 KJ g−1, 5.0×106 min−1, 90.8 KJ g−1, -126.5 JK−1 g−1, and 49.9 KJ g−1, respectively.

scholarly journals Determination of the degree of randomness in condensation copolymers containing both symmetrical and unsymmetrical monomer units: a theoretical study

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Martine Tessier ◽  
Alain Fradet
Keyword(s):  
Nmr Spectroscopy ◽  
Ethylene Terephthalate ◽  
Functional Group ◽  
Theoretical Study ◽  
Rational Functions ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Average Block

Abstract Expressions for the degree of randomness, B, and for the number- and weight-average block lengths of condensation copolymers containing both symmetrical (AA + BB) and unsymmetrical (AB) monomer units are established through an approach based on functional group probabilities. Several parameters introduced in literature to characterize randomness in AA + BB condensation copolymers are also calculated using this approach and compared to B, showing that they are simple linear or rational functions of B. A method for calculating functional group probabilities from the dyad and triad number-fractions determined by NMR spectroscopy is described for poly(ethylene terephthalate)-poly(ε-caprolactone) copolyesters. This method obviously applies to any AA + BB + AB polycondensation and is easily generalizable to other types of condensation copolymers.

scholarly journals Determination of diethyleneglycol content and number of carboxylic end groups in poly(ethylene terephthalate) fibers using imaging and conventional near infrared spectroscopy

2016 ◽  
Vol 49 ◽  
pp. 15-21 ◽  
Author(s):  
Viviane Fonseca Caetano ◽  
Lívia Rodrigues e Brito ◽  
Jarbas José Rodrigues Rohwedder ◽  
Celio Pasquini ◽  
Maria Fernanda Pimentel ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Ethylene Terephthalate ◽  
Near Infrared ◽  
Poly Ethylene Terephthalate ◽  
End Groups ◽  
Poly Ethylene
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