Kinetic Regularities of Canola Oil Amidation by Aminoethylethanolamine

Studies in Chemical Process Technology (SCPT) Volume 2, 2014 www.as‐se.org/scpt

Kinetic Regularities of Canola Oil Amidation

by Aminoethylethanolamine Kramarev Sergiy*1, Malik Sergii2 Technology of fats and fermentation products department, National Technical University "Kharkiv Polytechnic Institute", 61002, Frunze str. 21, Kharkiv, Ukraine *1

kramarevsergey@yahoo.com; 2malik_sg@ukr.net

Abstract Amidation reaction of canola oil with aminoethylethanolamine has been investigated. Researches have been conducted in batch reactor in temperature range from 140°C to 180°C and molar ratio of components is 1:3. Concentrations of reagents and main reaction products have been determined. Main regularities of formation and consumption of main components of reaction masses have been determined. Ratio constants of amidation reactions have been calculated. Determined that increasing of reaction temperature leads to significant speeding of reactions and as a result increasing of ration constants.

Keywords Amidation; Kinetic; Concentration; Canola Oil; Ratio Constant

Introduction Nitrogen‐containing surface‐active substances (SAS) are widely used in different industries for production of fabric softeners, antistatics, corrosion inhibitors, bactericides, emulsifiers, detergents etc [1, 2]. Substituted alkylimidazolines are one of the most commonly used among all nitrogen‐containing SAS. Properties of such compounds are highly dependant on substitute that connected with imidazoline ring [1‐3].

Including imidazoline type SAS one of the main type of raw materials for SAS production, is coconut oil or fatty acids of coconut oil [4]. Usage of other types of vegetable oils and fats, including oils with C18 acids, for SAS production is becoming more and more popular.

Processes and technologies of SAS producing from coconut oil are well researched [4]. Use of another type of raw material will lead to significant changes not only in properties of obtained products but in passing of reactions as well. Even though products of amidation of long chain oils are widely used in the industry, there is not enough information about these reactions. Researches of such reactions and obtaining new kinetic data interest the chemical industry.

Experiment Canola oil is one of the most popular oils for technical use. It produced in large quantities all around the world and that is the reason why canola oil has been used for these researches. Obtaining nitrogen containing substances of imidazoline type has been conducted by a direct amidation of canola oil with aminoethylethanolamine (AEEA). The reason why this amine has been chosen is that products of such reactions are hydroxyethylimidazolines, which are widely used imidazoline SAS. Reagents for that research were canola oil and aminoethylethanolamine supplied by Warenhandel GmbH & Co (Germany) and Merck KGaA (Germany) respectively.

These reactions have been conducted in batch reactor with automatic maintaining of temperature and continuous agitation. Reactor is equipped with nitrogen supply for preventing oxidation of reagents. Syntheses have been conducted during one hour intemperature range from 140°C to 180°C. Samples out of synthesis of reaction masses determine the aminoethyethanolamine, amidoamines, alkylimidazolines and acylglycerines content.

Results and Discussion It’s well known [5] that reactions of acylglycerol with amines, ammonia and other nucleophilic reagents are second order reactions and common scheme of such reactions could be presented as the following: TAG+AEEA →DAG+AA (1) DAG+AEEA →MAG+AA (2)

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MAG+AEEA →Gl+AA (3) Where MAG, DAG, TAG are mono‐ di‐ and tryglycerols respectively, Gl – glycerol, AA – amidoamines.

If identify all acylglycerols like AG these reactions will act as reaction (4) AG+AEEA →Gl+AA (4) Reactions 5‐7 could happen while there is a shortage of amine: TAG+AA →DAG+Dad (5) DAG+AA →MAG+Dad (6) MAG+AA →Gl+Dad (7) Or AG+AA →Gl+Dad (8) Where DAd is alkyldiamides of fatty acids.

It is very difficult for alkyldidamides to cyclize into alkylimidazolines [4] and that is the reason why producing of alkylimidazolines with high yields often use high molar ratios or 5‐10 % mol. or even more excess of amine. As a result, interactions between acylglycerols and amine occur preferably according to reactions 1‐3. In such case alkylimidazolines (AI) are formed according to reaction (9) [4, 6] AA ↔AI+H2O (9) Pictures 1‐4 represent changes in acylglycerol, amidoamines, alkylimidazolines and AEEA concentrations during reaction time.

FIG. 1 CHANGES IN CONCENTRATION OF ACYLGLYCEROLS DURING AMIDATION REACTION

FIG. 2 CHANGES IN CONCENTRATION OF AMINOETHYLETHANOLAMINE DURING AMIDATION REACTION

From Fig. 1 to Fig. 2 we can see that initial reagents of these reactions are continuously consumed, and consumption of AEEA is over than consumption of AG. The raising of temperature also leads to an acceleration in the reagents consumption.

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Studies in Chemical Process Technology (SCPT) Volume 2, 2014 www.as‐se.org/scpt

FIG. 3 CHANGES IN CONCENTRATION OF AMIDOAMINES DURING AMIDATION REACTION

FIG. 4 CHANGES IN CONCENTRATION OF ALKYLIMIDAZOLINES DURING AMIDATION REACTION

Products of reactions (AA and AI) have another behaviour: concentration of AA (Fig. 3) rapidly increases at the beginning of reaction, after that it stabilizes or even decreases, which could be interpreted as AA is precursor of AI and it transforms into AI during further reaction. Also AA can be consumed by reactions 5‐6 to form alkyldiamides.

Concentrations of AI (Fig. 4) as well as AA rapidly increase at the beginning of reaction than stabilizes and grow slightly. Temperature increase leads to increase in AA and AI concentration.

Reactions researched are often used as a first stage for producing imidazoline and the depth and speed of these reaction have a significant influence on quality of obtaining imidazolines. Kinetic data about all stages of amdation reaction are necessary for designing of proper equipment or determining rational technological parameters for imidazolines and/or their precursor’s production.

It’s well known that speed of chemical reaction can be determined from equation which for reaction (4) has following form [7, 8]: r=‐k*∙[AG]∙[AEEA] (10) r – speed of reaction; k* ‐ effective rate constant; [AG] – concentration of acylglycerols; [AEEA] – concentration of aminoethylethanolamine.

It must be noted that ratio constant in this equation is an effective ratio constant which means that it consists of a few individual ratio constants (reactions of TAG, DAG, MAG, reactions of individual acylglycerols etc.).

Moreover speed of chemical reactions could be determined as a slope tangent to kinetic curves in determined points . While the speed of reaction is known, it’s easy to calculate ratio constant from equation 10.

[7]

Curve Expert software has been used for kinetic curves analysis where speed of reaction in determined moments of time has been calculated. Ratio constants have been calculated according to equation 11: k*=‐r/([AG]∙[AEEA]) (11) Ratio constant represented in Table 1.

From Table 1 ratio constants increase with the temperature. Therefore, 40 degrees’ increase in the temperature leads to the increasing of ratio constant in ten times.

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TABLE 1 RATIO CONSTANTS FOR AMIDATION REACTIONS

Temperature, K (°C)

413 (140)

433 (160)

453 (180)

Ratio constant, l/mol•sec

0.000146

0.000651

0.00101

Conclusions The reaction of canola oil with aminoethylethanolamine has been investigated. These investigations focus on kinetic regularities of such reactions. As a result, ratio constants of amidation process have been calculated and dependence of this ratio constant from temperature has been determined. It showed that increase in temperature could significantly increase ratio constant and could speed the amidation process.

REFERENCES

[1]

R. Tyagi, V.K. Tyagi, S.K. Pandey. “Imidazoline and its derivatives: an overview.” Journal of oleo science 56 (2007): 211‐22.

[2]

D. Bajpai V.K. Tyagi. “Fatty imidazolines: chemistry, synthesis, properties and their industrial application.” Journal of oleo science 55(2006): 319‐29.

[3]

R.G. Bistline Jr., J.W. Hampson, W.M. Linfield. “Synthesis and properties of fatty imidazolines and their N‐(2‐aminoethyl) derivatives.” Journal of American oil chemists society 60(1983): 823‐28.

[4]

Faingold S.I., Kuusk A.E., Kiyk H.E. Chemistry of anionic and ampholitic nitrogen‐containing surface‐active substances Tallinn: Valgus, 1984.

[5]

Saiks P. Reaction mechanisms in organic chemistry Moscow: Chemistry, 1971.

[6]

Y. Wu, P.R. Herrington. “Thermal Reactions of fatty acids with diethylentriamine.” Journal of American oil chemists society 74 (1997): 61‐64.

[7]

G.E Froment, K.C. Waugh. Reaction kinetics and the development of catalytic processes Amsterdam: Elesivier, 2011.

[8]

F.D. Helfferich. Chemical kinetics Volume 40 Kinetics of multistep reactions 2‐nd edition Elesivier, 2004.

Kramarev Sergiy was born in Kharkiv, Ukraine in 1984. In 2007 was awarded to master’s degree with honour in specialty Technology of fats and fat substitutes. In 2013 he has defended his thesis for the degree of Ph.D which was devoted to surface‐ active substances obtaining technology for technical and food industries on specialty “Technology of fats, essential oils and perfume‐cosmetic products” in National Technical University “Kharkiv polytechnic institute” (Kharkiv, Ukraine).

In 2007 he started work in National Technical University “Kharkiv polytechnic institute” as a Research Engineer. In the same year he started to work in NHI Service Llc. as Research Associate. In 2011 he changed job to Junior Research Associate and in 2012 – Research Associate in National Technical University “Kharkiv polytechnic institute”. Also in 2011 he left position Research Associate in NHI Service Llc. and moved to the same position in Himintech Llc. For now he works as Postdoctoral Research Asociate in National Technical University “Kharkiv polytechnic institute”.

Dr. Kramarev has more than 30 scientific publications in reputed national journals most of which are devoted to surface active substances obtaining and usage technologies.

Malik Sergii was born in Murafa, Kharkivska oblast, Ukraine in 1986. In 2009 was awarded to master’s degree with honour in specialty Technology of fats and fat substitutes. In 2014 he has defended his Ph.D. thesises which was devoted tonitrogen‐ containing surfrace‐active substances obtaining in National Technical University “Kharkiv polytechnic institute” (Kharkiv, Ukraine).

In 2009 he started to work in National Technical University “Kharkiv polytechnic institute” as a Research Engineer and in NHI Service Llc. as Research Associate. In 2011 he changed job to Junior Research Associate. In 2012 he became Postgraduate Student of Technology of fats and fermentation products department of National Technical University “Kharkiv polytechnic institute”. For now he works as Research Associate in Himintech Llc. Dr. Malik has more than 25 scientific publications in reputed national journals.

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