Hydrolysis Kinetics of Cornstalk in Formic Acid Solution

2012 ◽  
Vol 535-537 ◽  
pp. 2438-2441
Author(s):  
Jun Ping Zhuang ◽  
Xue Ping Li
Keyword(s):  
Activation Energy ◽  
Acid Solution ◽  
Formic Acid ◽  
Wood Fiber ◽  
Hydrolysis Kinetics ◽  
Practical Applications ◽  
And Performance ◽  
Promising Source ◽  
Kinetics Of ◽  
Hydrolysis Of

Cornstalk, among the agricultural residues and other non-wood fiber, is a more promising source of lignocellulosic materials for bioethanol production. Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Kinetic models can have practical applications for the optimization of the process and performance analysis, or economic estimations, so investigate the cornstalk hydrolysis kinetics is necessary. In this paper, effects of temperature and time on cornstalk hydrolysis in saturated formic acid with 4% hydrochloric acid solution reaction kinetics have been investigated. The results showed that the hydrolysis velocities of cornstalk were 0.021 h−1 at 60 °C, 0.0302 h−1 at 65 °C and 0.060 h−1 at 70 °C, the degradation velocities of glucose were 0.061 h−1 at 60 °C, 0.0845 h−1 at 65 °C, and 0.24 h−1 at 70 °C, the activation energy of cornstalk hydrolysis was 99.60 kJ/mol, and the activation energy of glucose degradation was130.94 kJ/mol.

Kinetics of Bamboo Fiber Hydrolysis Reaction in Saturated Formic Acid

2012 ◽  
Vol 531-532 ◽  
pp. 679-683 ◽  
Author(s):  
Jun Ping Zhuang ◽  
Lu Lin ◽  
Chun Sheng Pang ◽  
Ying Liu
Keyword(s):  
Activation Energy ◽  
Hydrochloric Acid ◽  
Acid Solution ◽  
Formic Acid ◽  
Arrhenius Equation ◽  
Bamboo Fiber ◽  
Hydrolysis Reaction ◽  
Exponential Factor ◽  
Practical Applications ◽  
And Performance

Kinetic models can have practical applications for the optimization of the process and performance analysis, or economic estimations, so investigate the bamboo fiber kinetics is necessary. In this paper, effects of temperature and time on bamboo fiber hydrolysis in saturated formic acid with 4% hydrochloric acid solution reaction kinetics have been investigated. The rate constants, average apparent activation energy and frequency factors were evaluated according to the Arrhenius equation. The results showed that the hydrolysis velocities of bamboo fiber were 1.63×10-2 h-1 at 55 °C, 2.59×10-2 h-1 at 60 °C, 4.56×10-2 h-1 at 65 °C, 6.75×10-2 h-1 at 70 °C and 0.10 h-1 at 75 °C in formic acid solution with 4 % hydrochloric acid. The degradation velocities of glucose were 6.57×10-3 h-1 at 55 °C, 1.98×10-2 h-1 at 60 °C, 2.53×10-2 h-1 at 65 °C, 7.47×10-2 h-1 at 70 °C and 0.14 h-1 at 75 °C. The pre-exponential factor of Arrhenius equation of bamboo fiber hydrolysis reaction and glucose decomposition was 1.48×1014 h-1 and 2.32×1020 h-1 respectively. The activation energy of bamboo fiber hydrolysis was 87.65kJ/mol, and the activation energy of glucose degradation was 141.44kJ/mol.

Hydrolysis Kinetics of Wheat Straw in Saturated Formic Acid / 4% Hydrochloric Acid Solution

2011 ◽  
Vol 236-238 ◽  
pp. 138-141
Author(s):  
Jun Ping Zhuang ◽  
Lu Lin ◽  
Chun Sheng Pang ◽  
Ying Liu
Keyword(s):  
Activation Energy ◽  
Hydrochloric Acid ◽  
Acid Solution ◽  
Formic Acid ◽  
Wheat Straw ◽  
Hydrochloric Acid Solution ◽  
Alternative Energy ◽  
Cellulose Degradation ◽  
Hydrolysis Kinetics ◽  
Practical Applications

Lignocellulosic materials are regarded as an alternative energy source for bioethanol production to reduce our reliance on fossil fuels. Pretreatment is an essential step in the enzymatic hydrolysis of biomass and subsequent production of bioethanol. Adding formic acid with catalyst dosage (4%) in saturated formic acid will be good for cellulose degradation and glucose production; when the cellulose hydrolyses to glucose, the glucose degrades simultaneously. Kinetic models can have practical applications for the optimization of the process and performance analysis, or economic estimations, so investigate the wheat straw hydrolysis kinetics is necessary. In this paper, effects of temperature and time on wheat straw hydrolysis in saturated formic acid with 4% hydrochloric acid solution reaction kinetics have been investigated. The results showed that the hydrolysis velocities of wheat straw were 0.0190 h−1at 60 °C, 0.0325 h−1at 65 °C, 0.0683 h−1at 70 °C and 0.0931 at 75 °C. The degradation velocities of glucose were 0.0285 h−1at 55 °C, 0.0448 h−1at 65 °C, 0.1098 h−1at 70°C and 0.1436 h−1at 75 °C. The activation energy of wheat straw hydrolysis was 106.35kJ/mol, and the activation energy of glucose degradation was 111.00kJ/mol.

scholarly journals Influence of impurities of the transitional metals Fe, Ni, and Co on the hydrolysis kinetics of BH− 4 ions in alkaline solutions

2021 ◽  
Vol 21 (3) ◽  
pp. 164-170
Author(s):  
Irina M. Gamayunova ◽  
Keyword(s):  
Activation Energy ◽  
Catalytic Effect ◽  
Arrhenius Equation ◽  
Alkaline Solutions ◽  
Hydrolysis Kinetics ◽  
Transitional Metals ◽  
Hydrolytic Process ◽  
Kinetics Of ◽  
Hydrolysis Of ◽  
Influence Of Impurities

The influence of small amounts of the Fe, Co, and Ni impurities on the spontaneous hydrolytic process of borohydride was studied within a temperature range of 60–100°C. The object under study was a simulated solution containing 9.53 M of OH− ions and 0.14 M of BH− 4 ions, used as a fuel for borohydride fuel cells. The rate constant k of borohydride hydrolysis for a small amount of impurities at different temperature was estimated. The lowest non-accelerating concentrations of the impurities were established (∼10 ppm for iron; ∼1 ppm for cobalt). The strongest accelerating effect on the hydrolysis of BH− 4 ions was rendered by nickel impurities: self-hydrolysis was accelerated by 1.2 times for 1 ppm Ni. The ambiguous trend of the kinetic curves does not allow to accurately estimate the activation energy; however, the increased temperature enhances the catalytic effect of hydrolysis acceleration according to Arrhenius’ equation.

scholarly journals Kinetic Analysis of the Hydrolysis of Pentose-1-Phosphates Through Apparent Nucleoside Phosphorolysis Equilibrium Shifts

2020 ◽  
Author(s):  
Felix Kaspar ◽  
Peter Neubauer ◽  
Anke Kurreck
Keyword(s):  
Kinetic Analysis ◽  
Hydrolysis Kinetics ◽  
Equilibrium Thermodynamics ◽  
Apparent Increase ◽  
Equilibrium Conversion ◽  
Sugar Phosphates ◽  
Kinetics Of ◽  
Hydrolysis Of

<div>Ask what an equilibrium can do for you:</div><div>Hydrolysis of pentose-1-phosphates leads to an apparent increase of the equilibrium conversion in nucleoside phosphorolysis reactions. This information can be leveraged via equilibrium thermodynamics to determine the hydrolysis kinetics of in situ generated sugar phosphates, which are known to be elusive and difficult to quantify.<br></div>

THE NON-ENZYMATIC HYDROLYSIS OF ADENOSINE DIPHOSPHATE

1957 ◽  
Vol 35 (12) ◽  
pp. 1496-1503 ◽  
Author(s):  
K. A. Holbrook ◽  
Ludovic Ouellet
Keyword(s):  
Activation Energy ◽  
Aqueous Solution ◽  
Enzymatic Hydrolysis ◽  
Inorganic Phosphate ◽  
Adenosine Diphosphate ◽  
Hydrogen Ions ◽  
Kcal Mole ◽  
First Order ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of the non-enzymatic hydrolysis of adenosine diphosphate in aqueous solution have been studied at pH 3.5 to 10.5 and temperatures from 80° to 95 °C. The reaction has been followed by measuring colorimetrically the inorganic phosphate liberated according to the over-all reaction[Formula: see text]The reaction has been found to be first order with respect to ADP concentration and to be catalyzed by hydrogen ions. From rate studies at pH 8.0 an activation energy of 24.2 kcal./mole was derived. A mechanism is proposed to account for the observed facts and the mechanism for the hydrolysis of adenosine triphosphate is also discussed.

Research on Kinetics of Hydrolysis Preparation of Micro-Molecular Dextran

2013 ◽  
Vol 748 ◽  
pp. 295-298
Author(s):  
Shu Qiong Liao ◽  
Xiao Yu Peng ◽  
Xue Wang Zhang ◽  
Ke Lin Huang ◽  
Ben Wang ◽  
...  
Keyword(s):  
Activation Energy ◽  
Molecular Weight ◽  
Kinetics Equation ◽  
Temperature Range ◽  
Kinetics Of Hydrolysis ◽  
Kinetics Of ◽  
Hydrolysis Of

Micro-molecular dextran was prepared in sub-critical water and sub-critical Water/CO2by hydrolysis of dextran20. The obtained products were mainly characterized by GPC. The kinetics of hydrolysis of dextran20 has been studied in the temperature range of 423.15K-463.15K. It was found that the level of dextran20 hydrolysis in sub-critical water and sub-critical water/CO2was first level kinetics equation. The activation energy was also calculated. The results demonstrated that the molecular weight of micro-molecular dextran could be controlled.

Kinetics of aquation and base hydrolysis of the macrocyclic complex trans-Bromo(N-meso-5,12-dimethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene)nitro-cobalt(III) perchlorate

1976 ◽  
Vol 29 (10) ◽  
pp. 2319 ◽  
Author(s):  
GA Lawrance ◽  
RW Hay
Keyword(s):  
Activation Parameters ◽  
Macrocyclic Complex ◽  
Base Hydrolysis ◽  
Hydrolysis Kinetics ◽  
Rate Expression ◽  
Entropy Of Activation ◽  
Ph Range ◽  
Kinetics Of ◽  
Hydrolysis Of

The macrocyclic complex trans-[Co(dtcd)(NO2)Br] [ClO4] (dtcd = 5,12-dimethyl-l,4,8,1l-tetraaza-cyclotetradeca-4,ll-diene) has been prepared and its hydrolysis kinetics investigated. At 25�C and 0.1 M HN03 the aquation occurs with kaq = 6.2 x 10-3 s-1 to give the trans-Co(dtcd)(NO2)- (OH2)]2+ cation. The activation parameters at 298 K are ΔH? = 75.0 kJ mol-1 and ΔS? = -35.6 J K-1 mol-1. Hydrolysis of the bromide in the pH range 7.5-8.8 follows the rate expression kobs = kaq + kOH[OH-]. At 25�C (I = 0.1 M, NaClO4) kOH = 1.21 x 103 1. mol-1 s-1 with the activation parameters for base hydrolysis being ΔH? = 74.2 kJ mol-1 and ΔS? = +63.2 J K-1 mol-1 at 298 K. Aquation and base hydrolysis of the bromo complex at 25�C occur at rates 14 and 5 times faster respectively than those previously reported for the analogous trans-[Co(dtcd)(NO2)Cl]+ complex, the acceleration being due to a more favourable entropy of activation in each case.

THE NON-ENZYMATIC HYDROLYSIS OF p-NITROPHENYL PHOSPHATE

1958 ◽  
Vol 36 (4) ◽  
pp. 686-690 ◽  
Author(s):  
K. A. Holbrook ◽  
Ludovic Ouellet
Keyword(s):  
Activation Energy ◽  
Enzymatic Hydrolysis ◽  
Ionic Species ◽  
Kcal Mole ◽  
First Order ◽  
Colorimetric Measurement ◽  
Nitrophenyl Phosphate ◽  
Ph Range ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of the non-enzymatic hydrolysis of p-nitrophenyl phosphate have been studied in aqueous solution in the pH range 2.6 to 9.0 and at temperatures from 68.0°to 82.0 °C. The reaction has been followed by colorimetric measurement of the nitrophenol produced by the reaction[Formula: see text]The reaction is first order with respect to p-nitrophenyl phosphate and has an activation energy of 26.0 kcal./mole at pH 2.6. An explanation has been proposed in terms of the different rates of hydrolysis of the various ionic species of the ester present in solution.

Sign in / Sign up

Export Citation Format

Share Document