scholarly journals Kinetic Studies of Esterification of Rosin and Pentaerythritol

Processes ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 39
Author(s):  
Meiga Putri Wahyu Hardhianti ◽  
Rochmadi ◽  
Muhammad Mufti Azis
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Kinetic Studies ◽  
Side Reaction ◽  
Reaction Rates ◽  
Molar Ratio ◽  
Time Interval ◽  
Order Kinetic ◽  
Pentaerythritol Ester ◽  
Ester Formation

Esterification of rosin with pentaerythritol produces rosin pentaerythritol ester (RPE) which is widely used in paint, coating, and pressure-sensitive and hot-melt adhesive industries. Although RPE has excellent valuable applications and has been industrially produced, studies on the reaction kinetics have not been widely reported in the present literature. This work proposed a kinetic study of RPE synthesis by including a series of consecutive reactions forming mono-, di-, tri-, and tetra-ester with decarboxylation of rosin as a side reaction in the kinetics model. For esterification, the reaction rates were determined by the second-order kinetic model. The first-order kinetic order was proposed for decarboxylation. Kinetic experiments were performed at a temperature range of 260 °C to 290 °C. The initial molar ratio of pentaerythritol to rosin (in the mole of OH/COOH) used was between 0.8 and 1.2. A small amount of samples were withdrawn in certain time interval. The sample was analyzed to evaluate their acid and saponification number. Afterward, those experimental data were used to simulate and validate the proposed kinetic model. In general, the proposed model could capture the experimental data well. The resulting activation energies ranged from 65.81 to 129.13 kJ mol−1 for esterification and 233.00 kJ mol−1 for decarboxylation. This model also offers a new insight that correlates well with tetra-ester formation and the softening point.

scholarly journals Kinetics of Transesterification of Safflower Oil to Obtain Biodiesel Using Heterogeneous Catalysis

2016 ◽  
Vol 14 (4) ◽  
pp. 929-938 ◽  
Author(s):  
Gabriel E. Galván Muciño ◽  
Rubi Romero ◽  
Armando Ramírez ◽  
María Jesús Ramos ◽  
Ramiro Baeza-Jiménez ◽  
...  
Keyword(s):  
Experimental Data ◽  
Statistical Analysis ◽  
Heterogeneous Catalysis ◽  
Kinetic Model ◽  
Methyl Esters ◽  
Molar Ratio ◽  
Safflower Oil ◽  
Estimated Parameters ◽  
Kinetics Of ◽  
Best Fit

Abstract The kinetics of the transesterification of safflower oil and methanol catalyzed by K2O/NaX was studied and modeled. The influence of the oil-methanol initial molar ratio and amount of catalyst were investigated to achieve a maximum triglycerides conversion (99 %) and a final methyl esters content of 94 % ±1. A kinetic model based on an Eley–Rideal mechanism was found to best fit the experimental data when assuming methanol adsorption as determining step. Other models derived from Langmuir – Hinshelwood – Hougen –Watson (LHHW) mechanisms were rejected based on statistical analysis, mechanistic considerations and physicochemical interpretation of the estimated parameters.

Kinetic Studies on Sorption of Textile Dyes Using Lamina and Petiole Parts of Eichhornia crassipes

2008 ◽  
Vol 3 (2) ◽  
Author(s):  
S Renganathan ◽  
R Venkatakrishnan ◽  
P Gautam ◽  
Lima Rose Miranda ◽  
M Velan
Keyword(s):  
Diffusion Coefficient ◽  
Kinetic Model ◽  
Eichhornia Crassipes ◽  
Kinetic Studies ◽  
Reactive Dye ◽  
The Other ◽  
Order Kinetic ◽  
Uptake Capacity ◽  
Fast Red ◽  
Order Kinetic Model

Sorption capacity of two different parts of Eichhornia crassipes such as Lamina and Petiole on a Basic dye (Basic Aurophine-O), Acidic dye (Acid Fast Red-A) and Reactive dye (Brill Red-5B) was studied in a batch system. The maximum equilibrium uptake capacity of petiole was 25.5 mg/g for Basic Aurophine-O, 23.1 mg/g for Acid Fast Red-A and 0.18 mg/g for Brill Red-5B. The equilibrium uptake capacity of petiole was found to be more in Basic Aurophine-O dye when compared to all other dyes studied. The maximum equilibrium uptake capacity of lamina was 27.0 mg/g for Basic Aurophine-O, 25.2 mg/g for Acid Fast Red-A and 4.2 mg/g for Brill Red-5B. The equilibrium uptake capacity of lamina was found to be more in Basic Aurophine-O when compared to Brill Red-5B and Acid Fast Red-A dyes studied in the present investigation. From the result, it was observed that the uptake capacity of dyes using E. crassipes part Lamina was found to be more when compared to the other E. crassipes part of Petiole used in the present study. Sorption results were found to be fitted very well with the Pseudo-second order kinetic model when compared to Pseudo-first order kinetic model. The intra particle diffusion coefficient (Ki) and diffusion coefficient (Di) obtained for the removal of dyes studied using Lamina was found to be more when compared to the other part of Petiole. The polynomial equations are developed and can be used as a ready reckoner equation to find out the percentage color removal of dyes studied in the present investigation at different period of time intervals.

scholarly journals Development of Cerium Oxide/Corncob Nanocomposite: A Cost-Effective and Eco-Friendly Adsorbent for the Removal of Heavy Metals

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4464
Author(s):  
Sidra Gran ◽  
Rukhsanda Aziz ◽  
Muhammad Tariq Rafiq ◽  
Maryam Abbasi ◽  
Abdul Qayyum ◽  
...  
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Contact Time ◽  
Cost Effective ◽  
Particle Diffusion ◽  
Order Kinetic ◽  
Removal Of Heavy Metals ◽  
Intra Particle Diffusion ◽  
Order Kinetic Model ◽  
Pseudo Second Order

This research aims to assess the efficiency of the synthesized corncob as a cost-effective and eco-friendly adsorbent for the removal of heavy metals. Therefore, to carry out the intended research project, initially, the corncob was doped with nanoparticles to increase its efficiency or adsorption capacity. The prepared adsorbent was evaluated for the adsorption of cadmium (Cd) and chromium (Cr) from aqueous media with the batch experiment method. Factors that affect the adsorption process are pH, initial concentration, contact time and adsorbent dose. The analysis of Cd and Cr was performed by using atomic absorption spectrometry (AAS), while the characterization of the adsorbent was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results showed that there is a significant difference before and after corncob activation and doping with CeO2 nanoparticles. The maximum removal for both Cd and Cr was at a basic pH with a contact time of 60 min at 120 rpm, which is 95% for Cd and 88% for Cr, respectively. To analyze the experimental data, a pseudo-first-order kinetic model, pseudo-second-order kinetic model, and intra-particle diffusion model were used. The kinetic adsorption studies confirmed that the experimental data were best fitted with the pseudo-second-order kinetic model (R2 = 0.989) and intra-particle diffusion model (R2 = 0.979). This work demonstrates that the cerium oxide/corncob nanocomposite is an inexpensive and environmentally friendly adsorbent for the removal of Cd and Cr from wastewater.

scholarly journals Biosorption of Copper (II) from Aqueous Solution using a Combination of Orange Peels and Tea Waste

2021 ◽  
Vol 920 (1) ◽  
pp. 012039
Author(s):  
N N Noordin ◽  
A N Kamarudzaman ◽  
N R Rahmat ◽  
Z Hassan ◽  
M Abdul Wahab ◽  
...  
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Freundlich Isotherm ◽  
Isotherm Models ◽  
Operating Parameters ◽  
Contact Period ◽  
Order Kinetic ◽  
Orange Peels ◽  
Tea Waste ◽  
Order Kinetic Model

Abstract The ability of biosorbents, which are a combination of orange peels and tea waste to treat copper (II) using the biosorption method was examined. The experiment was performed under batch biosorption studies with various operating parameters. The pH, biosorbent dosage, contact time, and initial copper (II) concentration were optimized from pH 3 - 8, 0.25 - 1.0 g, 2 - 20 minutes and 10 - 100 mg/L, respectively. The findings found that a pH of 5.5, a biosorbent dosage of 0.75 g, a contact period of 5 minutes, and an initial copper (II) concentration of 10 mg/L were shown to be the best operating parameters for copper (II) biosorption. For isotherm models, the experimental data for copper (II) biosorption was fitted to the Langmuir isotherm with R2 value of 0.7775 compared to the Freundlich isotherm model with R2 value of 0.1073. The value for RL was 0.4, indicating that copper (II) biosorption using the combination of orange peels and tea waste is favourable. For kinetic models, the experimental data for copper (II) biosorption was well fitted to the pseudo-second-order kinetic model with R2 value of 0.9865 compared to the pseudo-first-order kinetic model with R2 value of 0.1006. In conclusion, the combination of orange peels and tea waste functions very well for biosorption of copper (II).

scholarly journals Kinetic Study on the Pyrolysis of Medium Density Fiberboard: Effects of Secondary Charring Reactions

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2481 ◽  
Author(s):  
Longwei Pan ◽  
Yong Jiang ◽  
Lei Wang ◽  
Wu Xu
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Kinetic Study ◽  
Mass Loss Rate ◽  
Medium Density Fiberboard ◽  
Kinetic Studies ◽  
Product Yield ◽  
Reaction Scheme ◽  
Medium Density ◽  
Pyrolysis Mechanism

The reaction models employed in the kinetic studies of biomass pyrolysis generally do not include the secondary charring reactions. The aim of this work is to propose an applicable kinetic model to characterize the pyrolysis mechanism of medium density fiberboard (MDF) and to evaluate the effects of secondary charring reactions on estimated products yields. The kinetic study for pyrolysis of MDF was performed by a thermogravimetric analyzer over a heating rate range from 10 to 40 °C/min in a nitrogen atmosphere. Four stages related to the degradation of resin, hemicellulose, cellulose, and lignin could be distinguished from the thermogravimetric analyses (TGA). Based on the four components and multi-component parallel reaction scheme, a kinetic model considering secondary charring reactions was proposed. A comparison model was also provided. An efficient optimization algorithm, differential evolution (DE), was coupled with the two models to determine the kinetic parameters. Comparisons of the results of the two models to experiment showed that the mass fraction (TG) and mass loss rate (DTG) calculated by the model considering secondary charring reactions were in better agreement with the experimental data. Furthermore, higher product yields than the experimental values will be obtained if secondary charring reactions were not considered in the kinetic study of MDF pyrolysis. On the contrary, with the consideration of secondary charring reactions, the estimated product yield had little error with the experimental data.

scholarly journals Biodiesel by Transesterification of Rapeseed Oil Using Ultrasound: A Kinetic Study of Base-Catalysed Reactions

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2229 ◽  
Author(s):  
José Encinar ◽  
Ana Pardal ◽  
Nuria Sánchez ◽  
Sergio Nogales
Keyword(s):  
Energy Savings ◽  
Methyl Esters ◽  
Reaction Times ◽  
Ultrasound Irradiation ◽  
Reaction Rates ◽  
Molar Ratio ◽  
Order Kinetic ◽  
Cold Filter Plugging Point ◽  
Operating Variables ◽  
Ultrasound Power

The objective of this work was to study the acceleration that ultrasound causes in the rate of biodiesel transesterification reactions. The effect of different operating variables, such as ultrasound power, catalyst (KOH) concentration and methanol:oil molar ratio, was studied. The evolution of the process was followed by gas chromatography, determining the concentration of methyl esters at different reaction times. The biodiesel was characterized by its density, viscosity, saponification and iodine values, acidity index, water content, flash and combustion points, cetane index and cold filter plugging point (CFPP), according to EN 14214 standard. High methyl ester yield and fast reaction rates were obtained in short reaction times. Ultrasound power and catalyst concentration had a positive effect on the yield and the reaction rate. The methanol:oil molar ratio also increased the yield of the reaction, but negatively influenced the process rate. The reaction followed a pseudo-first order kinetic model and the rate constants at several temperatures were determined. The activation energy was also determined using the Arrhenius equation. The main conclusion of this work is that the use of ultrasound irradiation did not require any additional heating, which could represent an energy savings for biodiesel manufacture.

scholarly journals Adsorption characteristics of Cu2+ on NiFe2O4 magnetic nanoparticles

2014 ◽  
Vol 5 (2) ◽  
pp. 223-230
Author(s):  
Farid Moeinpour ◽  
Shohreh Kamyab
Keyword(s):  
Experimental Data ◽  
Electron Microscope ◽  
Magnetic Nanoparticles ◽  
Kinetic Model ◽  
Aqueous Solutions ◽  
Copper Ions ◽  
Order Kinetic ◽  
Experimental Conditions ◽  
Order Kinetic Model ◽  
Nife2o4 Nanoparticles

Magnetic NiFe2O4 nanoparticles have been synthesized and used as adsorbents for copper removal from aqueous solution. The NiFe2O4 nanoparticles were characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy. The batch removal of Cu2+ ions from aqueous solutions using NiFe2O4 magnetic nanoparticles under different experimental conditions was investigated. The effects of initial concentration, adsorbent dose, contact time, and pH were investigated. The adsorption process was pH dependent, and the maximum adsorption was observed at a pH of 6.0. Equilibrium was achieved for copper ion after 25 min. Experimental results showed that NiFe2O4 magnetic nanoparticles are effective for the removal of copper ions from aqueous solutions. The pseudo-second-order kinetic model gave a better fit of the experimental data as compared to the pseudo-first-order kinetic model. Experimental data showed a good fit with the Langmuir isotherm model.

scholarly journals Kinetic modeling of canola oil transesterification catalyzed by quicklime

2018 ◽  
Vol 16 (6) ◽  
Author(s):  
J.N. Camacho ◽  
G. E. Galván Muciño ◽  
S.L. Martínez Vargas ◽  
C. Pérez Alonso ◽  
R. Natividad
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Canola Oil ◽  
Reaction Rate ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
Minor Effect ◽  
Whole Process ◽  
High Effect ◽  
Kinetics Of

This work aimed to study and model the kinetics of transesterification of canola oil with methanol catalyzed by calcined quicklime (CaO + MgO). The influence of three main variables was studied at 328 K: reagents order addition (has a negligible effect on the reaction), methanol-oil molar ratio (has minor effect on reaction rate after 1.5 h of reaction) and catalyst loading (high effect on reaction rate) to achieve at least a triglycerides conversion of 96.5% in concordance with norm EN 14103. A kinetic model based on an Eley-Rideal mechanism was found to well fit (R2 = 0.9886) the experimental data. Thus, it was concluded that for the quicklime catalyzed transesterification of canola oil with methanol to occur, first the methanol must be chemisorbed and the resulting methoxy species react with triglycerides in the interface liquid-solid. The whole process is limited by this step since methanol readily adsorbs onto the catalytic surface.

scholarly journals Investigating the Reaction and Transport Controlled Mechanism for the Sorption of Cr(III) and Mn(II) Ions onto Acid Activated Shale using Non-Linear Error Functions

2019 ◽  
Vol 3 (1) ◽  
pp. 174-185
Author(s):  
I. R. Ilaboya ◽  
O. C. Izinyon
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Kinetic Models ◽  
Metal Ion ◽  
Second Order ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Linear Coefficient ◽  
Non Linear ◽  
Pseudo Second Order

Time dependent adsorption study on the sorption of Cr(III) and Mn(II) ions onto acid activated shale was conducted using batch adsorption techniques to investigate the effect of initial metal ion concentration on the process of adsorption. Experimental data obtained were fitted into different kinetic models to analyze the mechanism of adsorption in terms of reaction controlled and transport controlled mechanism. Some of the selected kinetic models include; Pseudo-first order, Pseudo-second order, Elovich, Film diffusion, Parabolic diffusion and Intra-particle diffusion model. From the result, it was observed based on the linear coefficient of determination (r2) that the experimental data fitted well into the various kinetic model tested. Application of non-linear error function such as error sum of square (SSE), root mean square error (RMSE) and residual average (RA) revealed that the rate limiting step for the adsorption of Cr3+ and Mn2+ ions on acid activated shale was chemical attachment (chemisorption) and the reaction mechanism follows the Pseudo-second order kinetic model.

scholarly journals Kinetic Study of 17α-Estradiol Activity in Comparison with 17β-Estradiol and 17α-Ethynylestradiol

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 634
Author(s):  
Tereza Bosakova ◽  
Antonin Tockstein ◽  
Zuzana Bosakova ◽  
Katerina Komrskova
Keyword(s):  
Experimental Data ◽  
Plasma Membrane ◽  
Kinetic Model ◽  
Critical Level ◽  
Membrane Lipid ◽  
Molar Ratio ◽  
Plasma Membrane Lipid ◽  
Membrane Lipid Bilayer ◽  
17Β Estradiol ◽  
New Interactions

17α-estradiol (αE2), an endogenous stereoisomer of the hormone 17β-estradiol (E2), is capable of binding to estrogen receptors (ER). We aimed to mathematically describe, using experimental data, the possible interactions between αE2 and sperm ER during the process of sperm capacitation and to develop a kinetic model. The goal was to compare the suggested kinetic model with previously published results of ER interactions with E2 and 17α-ethynylestradiol (EE2). The HPLC-MS/MS method was developed to monitor the changes of αE2 concentration during capacitation. The calculated relative concentrations Bt were used for kinetic analysis. Rate constants k and molar ratio n were optimized and used for the construction of theoretical B(t) curves. Modifications in αE2–ER interactions were discovered during comparison with models for E2 and EE2. These new interactions displayed autocatalytic formation of an unstable adduct between the hormone and the cytoplasmic receptors. αE2 accumulates between the plasma membrane lipid bilayer with increasing potential, and when the critical level is reached, αE2 penetrates through the inner layer of the plasma membrane into the cytoplasm. It then rapidly reacts with the ER and creates an unstable adduct. The revealed dynamics of αE2–ER action may contribute to understanding tissue rejuvenation and the cancer-related physiology of αE2 signaling.

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