Pyrolysis of Solid Digestate from Sewage Sludge and Lignocellulosic Biomass: Kinetic and Thermodynamic Analysis, Characterization of Biochar

This study investigates the pyrolysis behavior and reaction kinetics of two different types of solid digestates from: (i) sewage sludge and (ii) a mixture of sewage sludge and lignocellulosic biomass—Typha latifolia plant. Thermogravimetric data in the temperature range 25–800 °C were analyzed using Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose kinetic methods, and the thermodynamic parameters (ΔH, ΔG, and ΔS) were also determined. Biochars were characterized using different chemical methods (FTIR, SEM–EDS, XRD, heavy metal, and nutrient analysis) and tested as soil enhancers using a germination test. Finally, their potential for biosorption of NH4+, PO43−, Cu2+, and Cd2+ ions was studied. Kinetic and thermodynamic parameters revealed a complex degradation mechanism of digestates, as they showed higher activation energies than undigested materials. Values for sewage sludge digestate were between 57 and 351 kJ/mol, and for digestate composed of sewage sludge and T. latifolia between 62 and 401 kJ/mol. Characterizations of biochars revealed high nutrient content and promising potential for further use. The advantage of biochar obtained from a digestate mixture of sewage sludge and lignocellulosic biomass is the lower content of heavy metals. Biosorption tests showed low biosorption capacity of digestate-derived biochars and their modifications for NH4+ and PO43− ions, but high biosorption capacity for Cu2+ and Cd2+ ions. Modification with KOH was more efficient than modification with HCl. The digestate-derived biochars exhibited excellent performance in germination tests, especially at concentrations between 6 and 10 wt.%.

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Kinetic and Thermodynamic Analysis of Two Carboxymethylcellulases from Macrotermes subhyalinus Little Soldier

International Journal of Biology ◽

10.5539/ijb.v9n4p17 ◽

2017 ◽

Vol 9 (4) ◽

pp. 17

Author(s):

Jean B. Fagbohoun ◽

Mankambou J. Gnanwa ◽

Fankroma M. T. Kone ◽

S. Dabonne ◽

Patrice L. Kouame

Keyword(s):

Thermodynamic Parameters ◽

Thermal Inactivation ◽

Molecular Conformation ◽

Residual Activity ◽

Degradation Kinetic ◽

Macrotermes Subhyalinus ◽

Kinetic And Thermodynamic Parameters ◽

Technology Applications ◽

Kinetic And Thermodynamic Analysis ◽

Increasing Temperature

Optimization of thermal processes relies on adequate degradation kinetic models to warrant food safety and quality. The knowledge on thermal inactivation of enzymes is necessary to allow their proper utilization in food industry and technology applications, enabling the reduction of heating times and optimization of heating temperatures. In this work, the kinetic of thermal inactivation was studied for the previously characterized carboxylmethylcellulases Ab-CX1 and Ab-CX2 from Macrotermes subhyalinus little soldier. Samples of carboxymethylcellulases were treated at different time-temperature combinations in the range of 5-60 min at 50-65°C and the kinetic and thermodynamic parameters for carboxymethylcellulases were calculated. Results showed that inactivation followed a first-order reaction with k-values between 0.0103 ± 0.0003 to 0.1217 ± 0.0005 and 0.0149 ± 0.0007 to 0.0416 ± 0.0003 min-1 for Ab-CX1 and Ab-CX2, respectively. At high temperatures, Ab-CX2 was less resistant, with a significant decrease in residual activity compared to Ab-CX1. The D- and k-values decreased and increased, respectively, with increasing temperature, indicating faster inactivation of carboxymethylcellulases. Activation energy (Ea) and Z-values were estimated to 76.74 ± 1.98 kJ.mol-1 and 24.21 ± 1.92 °C for Ab-CX1, 62.80 ± 2.05 kJ.mol-1 and 33.33 ± 2.78 °C for Ab-CX2. Thermodynamic parameters (ΔH#, ΔS# and ΔG#) were also calculated. The high value obtained for the variation in enthalpy of activation indicates that a high amount of energy is required to initiate denaturation, probably due to the molecular conformation of carboxymethylcellulases. All results suggest that both carboxymethylcellulases are relatively resistant to long heat treatments up to 50°C.

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Kinetic and Thermodynamic Analysis of Dimerization Inhibitors Binding to HIV Protease Monomers by Surface Plasmon Resonance

Biomeditsinskaya Khimiya ◽

10.18097/pbmc20125801043 ◽

2012 ◽

Vol 58 (1) ◽

pp. 43-49 ◽

Cited By ~ 3

Author(s):

P.V. Ershov ◽

O.V. Gnedenko ◽

A.A. Molnar ◽

A.V. Lisitsa ◽

A.S. Ivanov ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

Complex Formation ◽

Thermodynamic Parameters ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Hiv Protease ◽

Kinetic And Thermodynamic Parameters ◽

Kinetic And Thermodynamic Analysis ◽

Kinetic Equilibrium ◽

Dimerization Inhibitors

Here, we describe the analysis of kinetic and thermodynamic parameters for binding of peptide and nonpeptide dimerization inhibitors to immobilized HIV protease (HIVp) monomers by using surface plasmon resonance. Molecular interactions were investigated at different inhibitors concentrations (0-80 μM) and temperatures (15-35°C). The kinetic, equilibrium and thermodynamic parameters have been determined. It was found that both inhibitors were characterized by similar interaction parameters. The complex formation is entropically driven process for both inhibitors. The entropic term(-ТΔS) had the value about -20 kcal/mol while the enthalpic term (ΔH) had the positive value about 14 kcal/mol and counteracted the complex formation.

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Biosorption of Hexavalent Chromium Metal Ions by Lentinula Edodes Biomass: Kinetic, Isothermal, and Thermodynamic Parameters

Acta Chimica Slovenica ◽

10.17344/acsi.2020.6408 ◽

2021 ◽

Vol 68 (3) ◽

pp. 587-593

Author(s):

Aslı Göçenoğlu Sarıkaya

Keyword(s):

Thermodynamic Parameters ◽

Hexavalent Chromium ◽

Lentinula Edodes ◽

Freundlich Isotherm ◽

Chromium Concentration ◽

Infrared Spectrometry ◽

Order Kinetic ◽

Biosorption Capacity ◽

Kinetic And Thermodynamic Parameters ◽

Biosorption Process

Lentinula edodes was investigated as a biosorbent for hexavalent chromium biosorption in this study. To examine the optimum conditions of biosorption, the pH of the hexavalent chromium solution, biosorbent dosage, temperature, contact time, and initial hexavalent chromium concentration were identified. Further, to clarify the biosorption mechanism process, the isothermal, kinetic, and thermodynamic parameters were determined. The functional groups and surface morphology of the biosorbent were identified using Fourier transform infrared spectrometry and scanning electron microscopy in the absence and presence of hexavalent chromium, respectively. Based on the results, the maximum biosorption capacity was determined as 194.57 mg g–1 under acidic conditions at 45 °C. From the kinetics studies, the biosorption process was observed to follow the Freundlich isotherm and pseudo-second-order kinetic models well. Thus, L. edodes as a biosorbent has potential usage for wastewater treatment owing to its effective biosorption capacity.

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Faculty Opinions recommendation of The immunoglobulin heavy chain constant region affects kinetic and thermodynamic parameters of antibody variable region interactions with antigen.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1082953.535922 ◽

2007 ◽

Author(s):

David Kranz

Keyword(s):

Thermodynamic Parameters ◽

Heavy Chain ◽

Variable Region ◽

Immunoglobulin Heavy Chain ◽

Constant Region ◽

Kinetic And Thermodynamic Parameters ◽

Heavy Chain Constant Region

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Solid Phase Extraction of Pb(II) in Water Samples on Amberlyst 36 and Determination of the Equilibrium, Kinetic and Thermodynamic Parameters of the Adsorption

Current Analytical Chemistry ◽

10.2174/1573411011309030021 ◽

2013 ◽

Vol 9 (3) ◽

pp. 513-521 ◽

Cited By ~ 2

Author(s):

Adalet Tunceli ◽

Ozcan Yalcinkaya ◽

Ali Rehber Turker

Keyword(s):

Solid Phase Extraction ◽

Thermodynamic Parameters ◽

Water Samples ◽

Solid Phase ◽

Phase Extraction ◽

Kinetic And Thermodynamic Parameters

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Kinetic and thermodynamic parameters for tRNA binding to the ribosome and for the translocation reaction.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)42890-6 ◽

1992 ◽

Vol 267 (7) ◽

pp. 4703-4712 ◽

Cited By ~ 1

Author(s):

S Schilling-Bartetzko ◽

A Bartetzko ◽

K.H. Nierhaus

Keyword(s):

Thermodynamic Parameters ◽

Kinetic And Thermodynamic Parameters ◽

Trna Binding

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Biosorption and Diffusion Modeling of Pb(II) by Malt Bagasse

International Journal of Chemical Engineering ◽

10.1155/2016/4210561 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 4

Author(s):

Klaiani B. Fontana ◽

Giane Gonçalves Lenzi ◽

Erica R. L. R. Watanabe ◽

Ervin Kaminski Lenzi ◽

Juliana A. M. T. Pietrobelli ◽

...

Keyword(s):

Sorption Process ◽

Isotherm Models ◽

Diffusion Modeling ◽

Biosorption Capacity ◽

Kinetic And Thermodynamic Parameters ◽

Pseudo Second Order ◽

Ph Optimization ◽

Kinetics Of ◽

And Diffusion

The removal of Pb(II) from water by biosorption processes onto malt bagasse was investigated and the kinetic and thermodynamic parameters were obtained; additionally a diffusion modeling was proposed. The characterization of malt bagasse was performed by FTIR and SEM/EDS. The experiments were conducted in batch system and an experimental design based response surface methodology was applied for agitation speed and pH optimization. The kinetics of biosorption followed pseudo-second-order model and the temperature of the process affected the biosorption capacity. Isotherm models of Langmuir, Freundlich, and Elovich were applied and the Langmuir model showed better fit and the estimated biosorption capacity was 29.1 mg g−1. The negative values obtained for ΔG° and positive values of ΔH° confirm, respectively, the spontaneous and endothermic nature of the process. The diffusion modeling was performed based on experiments in the absence of agitation to investigate the influence of the biosorbent on the sorption process of Pb(II) ions.

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