scholarly journals Kinetic Modeling of Solketal Synthesis from Glycerol and Acetone Catalyzed by an Iron(III) Complex

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 83
Author(s):  
Francesco Taddeo ◽  
Roberto Esposito ◽  
Vincenzo Russo ◽  
Martino Di Serio
Keyword(s):  
Reaction Mechanism ◽  
Vegetable Oils ◽  
Kinetic Modeling ◽  
Batch Reactor ◽  
Reaction Network ◽  
Pharmaceutical Formulations ◽  
Animal Fats ◽  
Reliable Model ◽  
Negative Effect ◽  
Thermodynamic And Kinetic Parameters

In the last few years, the depletion of the fossil sources and their negative effect on the environment has led to find new alternatives; among these, biodiesel is considered one of the most promising for this purpose. Biodiesel can be produced from the transesterification of vegetable oils or animal fats, obtaining glycerol as a by-product. Glycerol can be used in different processes and one of the most interesting is the condensation with acetone to produce solketal. Among its applications, plasticizers, solvents, and pharmaceutical formulations are the most common. In this work, the attention was focused on the reaction between glycerol and acetone to give solketal promoted by an iron(III) complex. The reaction mechanism was hypothesized, and the kinetics was studied in a batch reactor. Finally, the thermodynamic and kinetic parameters were determined with a reliable model investigating the phenomena that occurred in the reaction network.

Microbial Activity Evolution during the Acclimation of a Mixed Culture to Phenol: Use of CO2 Evolution Rate as Indicator

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2049-2052 ◽  
Author(s):  
G. Buitrón ◽  
A. Koefoed ◽  
B. Capdeville
Keyword(s):  
Microbial Activity ◽  
Control Parameter ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Evolution Rate ◽  
Biodegradation Rate ◽  
Carbon Dioxide Evolution ◽  
Carbon Dioxide Evolution Rate ◽  
Infra Red ◽  
Negative Effect

The microbial activity during the aerobic acclimation of activated sludge to phenol was studied. Carbon dioxide evolution rate (CER), measured in a sequencing batch reactor coupled to an infra-red system, was utilized as the activity control parameter. It was found that CER is representative of the microbial metabolism. Moreover, it was observed that starvation periods during acclimation had a negative effect on biodegradation rate.

Tandem synthesis of tetrahydroquinolines and identification of reaction network by operando NMR

2021 ◽  
Author(s):  
Jingwen Chen ◽  
Long Qi ◽  
Biying Zhang ◽  
Minda Chen ◽  
Takeshi Kobayashi ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Complex Network ◽  
Reaction Network ◽  
Tandem Reactions ◽  
Organic P ◽  
Design And Optimization ◽  
Metal Organic ◽  
Tandem Synthesis

The study of the reaction mechanism and complex network for heterogeneously catalyzed tandem reactions is challenging but can guide reaction design and optimization. Here, we describe using a bifunctional metal-organic...

scholarly journals ANÁLISE DE PESTICIDAS ORGANOCLORADOS EM ÓLEOS VEGETAIS POR CROMATOGRAFIA GASOSA DE ALTA RESOLUÇÃO (HRGC)

2018 ◽  
Vol 35 (3) ◽  
pp. 189
Author(s):  
Eudécio Bonfim dos Santos Dias ◽  
Eliane Da Costa Vilela ◽  
Fernando Mauro Lanças
Keyword(s):  
Solid Phase Extraction ◽  
Vegetable Oil ◽  
Vegetable Oils ◽  
Concentration Level ◽  
Solid Phase ◽  
Agricultural Products ◽  
Phase Extraction ◽  
Human Diet ◽  
Animal Fats ◽  
Chemical Products

Vegetable oil were introduced in human diet in the last decade to change the use of animal fats. The chemical products althrought utilized in correct manner can cause residues in food bring to healt there be a necessity of a constant monitoring of the concentration level the several agricultural products. The answer to this necessity has motivated the development of several of a methodology for simultaneous analysis of aldrin, dieldrin, endrin and endosulfanin vegetable oils by HRGC, using solid phase extraction (SPE) using silica and XAD-2. The recovery was 70-110%.

scholarly journals Pre-Treatment of Waste Frying Oils for Biodiesel Production

2015 ◽  
Vol 9 (7) ◽  
pp. 99 ◽  
Author(s):  
Nyoman Puspa Asri ◽  
Diah Agustina Puspita Sari
Keyword(s):  
Raw Materials ◽  
Batch Reactor ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
High Price ◽  
Composite Catalyst ◽  
Frying Oils ◽  
Animal Fats ◽  
Waste Frying Oils ◽  
Pre Treatment

Synthesis of biodiesel is a strategic step in overcoming energy scarcity and the environmental degradationcaused by the continuous use of the petroleum based energy. Biodiesel as an alternative fuel for diesel engine isproduced from renewable resources such as vegetable oils and animal fats. The main obstacle in the biodieselproduction is the high price of the raw materials, resulting in the price of biodiesel is not competitive comparedto the petroleum diesel. Therefore, the use of waste frying oils (WFO) is one way to reduce the cost of biodieselproduction, because of its availability and low price. In the present work, WFO from California Fried chicken(CFC) restaurants in Surabaya were used as feed stock for the biodiesel production. The experiments wereconducted using three steps of processes: pre-treatment of WFO, preparation of alumina based compositecatalyst CaO/KI/γ-Al2O3 and transesterification of treated WFO. WFO was treated by several types and variousamounts of activated adsobents. The treated WFO was transesterified in three neck glass batch reactor withrefluxed methanol using CaO/KI/γ-Al2O3. The results reveal that the best method for treating WFO is using 7.5%(wt. % to WFO) of coconut coir. Alumina based composite catalyst CaO/KI/γ-Al2O3 was very promising fortransesterification of WFO into biodiesel. The yield of biodiesel was 83% and obtained at 65ºC, 5 h of reactiontime, 1:18 of molar ratio WFO to methanol and 6% amount of catalyst.

Reactor Design for Complex Reactions

2001 ◽  
Author(s):  
L. K. Doraiswamy
Keyword(s):  
Batch Reactor ◽  
Plug Flow ◽  
Reaction Network ◽  
Reactor Design ◽  
Batch Reactors ◽  
Complex Reaction ◽  
Mixed Flow ◽  
Flow Reactors ◽  
Design Procedures ◽  
Reactor Types

Procedures were formulated in Chapter 5 for treating complex reactions. We now turn to the design of reactors for such reactions. Continuing with the ethylation reaction, we consider the following reactor types for which design procedures were formulated earlier in Chapter 4 for simple reactions: batch reactors, continuous stirred reactors (or mixed-flow reactors), and plug-flow reactors. However, we use the following less formal nomenclature: A = aniline, B = ethanol, C = monoethyaniline, D = water, E = diethylaniline, F = diethyl ether, and G = ethylene. The four independent reactions then become Using this set of equations as the basis, we now formulate design equations for various reactor types. Detailed expositions of the theory are presented in a number of books, in particular Aris (1965, 1969) and Nauman (1987). Consider a reaction network consisting of N components and M reactions. A set of N ordinary differential equations, one for each component, would be necessary to mathematically describe this system. They may be concisely expressed in the form of Equation 5.5 (Chapter 5), or . . . d(cV)/dt = vrV (11.1) . . . The use of this equation in developing batch reactor equations for a typical complex reaction is illustrated in Example 11.1.

Rate Coefficients and Mechanisms of Atmospheric Oxidation of the Esters

2011 ◽  
Author(s):  
Jack Calvert ◽  
Abdelwahid Mellouki ◽  
John Orlando ◽  
Michael Pilling ◽  
Timothy Wallington
Keyword(s):  
Vegetable Oils ◽  
Methyl Esters ◽  
Ambient Air ◽  
Consumer Products ◽  
Anthropogenic Sources ◽  
Atmospheric Oxidation ◽  
Rate Coefficients ◽  
Oh Radicals ◽  
Loss Mechanism ◽  
Animal Fats

Esters are emitted directly into the atmosphere from both natural and anthropogenic sources and are produced during the atmospheric oxidation of ethers. Methyl acetate and ethyl acetate have found widespread use as solvents. Vegetable oils and animal fats are esters. Transesterification of vegetable oils and animal fats with methanol gives fatty acid methyl esters (FAMEs) which are used in biodiesel. Many esters have pleasant odors and are present in essential oils, fruits, and pheromones, and are often added to fragrances and consumer products to provide a pleasant odor. Table VII-A-1 provides a list of common esters and their odors. It is surprising to note that despite their ubiquitous nature, volatility, and fragrance, it is only very recently that quantitative measurements of esters in ambient air have been reported (Niedojadlo et al., 2007; Legreid et al., 2007). The atmospheric oxidation of saturated esters is largely initiated by OH radical attack. Reaction with O3 and NO3 radicals contributes to the atmospheric oxidation of unsaturated esters. As discussed in chapter IX, UV absorption by esters is only important for wavelengths below approximately 240 nm and, hence, photolysis is not a significant tropospheric loss mechanism. When compared to the ethers from which they can be derived, the esters are substantially less reactive towards OH radicals. The ester functionality —C(O)O— in R1C(O)OR2 deactivates the alkyl groups to which it is attached with the deactivation being most pronounced for the R1 group attached to the carbonyl group. The atmospheric oxidation mechanisms of the esters are reviewed in the present chapter. The reaction of OH with methyl formate has been studied by Wallington et al. (1988b) and Le Calvé et al. (1997a) over the temperature range 233–372 K. Data are summarized in table VII-B-1 and are plotted in figure VII-B-1. The room temperature determination of k(OH + CH3OCHO) by Wallington et al. is in agreement with that by Le Calvé et al. (1997) within the experimental uncertainties. Significant curvature is evident in the Arrhenius plot in figure VII-B-1.

Experimental and Kinetic Modeling Study of Autoignition Characteristics ofn-Heptane/Ethanol by Constant Volume Bomb and Detail Reaction Mechanism

2017 ◽  
Vol 31 (12) ◽  
pp. 13610-13626 ◽  
Author(s):  
Runzhao Li ◽  
Zhongchang Liu ◽  
Yongqiang Han ◽  
Manzhi Tan ◽  
Yun Xu ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Kinetic Modeling ◽  
Constant Volume ◽  
Modeling Study
Sign in / Sign up

Export Citation Format

Share Document