*3.3.1 Synthesis of imidazolines*

Tripathy et al. (2016) has synthesized the imidazoline using microwave synthesizer. Different compounds were taken in the beaker such as diethylenetriamine (20 mmol), fatty acids (Myristic acid, stearic acid, Lauric acid, Palmitic acid and Oleic acid- 40 mmol) and calcium oxide (20 g). The reaction was occurred at appropriate temperature as set in microwave. Later on, the mixture was cool down at room temperature. Then it further processed by adding the 80–100 ml of ethyl acetate and boiled, the remaining mixture was filtrated out and dried using vacuum. The optimization has been done and product was yielded at its maximum. The characterization and purity of the product was analyzed by spectrum [33].

**71**

**Figure 7.**

*Gemini Imidazolinium Surfactants: A Versatile Class of Molecules*

*3.3.2 Synthesis of cationic Gemini imdazoline using waste frying oil*

The synthesis of cost effective gemini imidazoline has also been reported by using waste frying oil like rapeseed oil, soyabean oil etc. The gemini imidazoline thus prepared have been analyzed for their surface active and performance properties. When compared to their monomeric counterparts, these geminis were found to

be many folds superior to their corresponding monomeric counterparts [33].

*3.3.3 Synthesis of cationic Gemini imidazoline surfactants with carbonate linkage*

Tripathy et al. (2016) synthesized gemini imidazoline by the reaction of monomeric imidazoline and di iodoalkyl carbonated under microwave irradiation. Synthesis of di (iodoethyl) carbonate as quaternizing has been achieved by mixing the iodo alkanol and diphenyl carbonate (1:2 molar ratio) acted as carbonate exchange reaction in acetone at room temperature [22]. The resultant product was recrystallized by adding ethyl acetate and acetone (50:50) in it. The obtained product was Gemini imidazoline which further characterized by spectral analysis [33].

*3.3.4 Synthesis of imidazoline-based dissymmetric bis-quaternary ammonium* 

*Synthesis of imidazoline-based dissymmetric bis-quaternary ammonium Gemini surfactant [34].*

Compound (I)N-(3-chloro-2-hydroxypropyl)-N, N-dimethyl alkylammonium chloride was formed by constantly mixing the N, N-dimethyl alkylamine hydrochloride, N, N-dimethyl alkylamine, and epichlorohydrin (1:1:1 molar ratio) for 14 hours in absolute ethanol. A light-yellow mixture has been obtained due to subsequently rotary evaporation of the ethanol. This product was further processed by repeated recrystallization from n-hexane and acetone to attained the white solid crude product. As per the study of this paper, compound (I) produced around 84.30% with the melting point of 47–48°C. The dissymmetric bis-quaternary ammonium salt with imidazoline ring (compound (II)) was synthesized using

*DOI: http://dx.doi.org/10.5772/intechopen.94209*

*Gemini surfactant*

**Figure 6.** *Quaternization of the Bisalkyl-bis-imidazoline intermediate [21].*

*Colloids - Types, Preparation and Applications*

*Synthesis of Bisalkyl-bis-imidazoline intermediate [21].*

Isopropyl alcohol or water mixture was added to it with continuation for 8 hours at 80–90 C. simultaneously, the pH of the solution has been around 8–9 by mixing the 10 wt.% NaOH solution. The supernatant liquid of the obtained product was taken in a beaker and mixed with 95% of alcohol for recrystallization. With the use of anhydrous alcohol, unreacted salts were removed from the solution. Thus, it resulted in the final

Tripathy et al. (2016) has synthesized the imidazoline using microwave synthesizer. Different compounds were taken in the beaker such as diethylenetriamine (20 mmol), fatty acids (Myristic acid, stearic acid, Lauric acid, Palmitic acid and Oleic acid- 40 mmol) and calcium oxide (20 g). The reaction was occurred at appropriate temperature as set in microwave. Later on, the mixture was cool down at room temperature. Then it further processed by adding the 80–100 ml of ethyl acetate and boiled, the remaining mixture was filtrated out and dried using vacuum. The optimization has been done and product was yielded at its maximum. The characterization and purity of the product was analyzed by spectrum [33].

product by removing the amide using chloroform [21] (**Figure 6**).

**3.3 Synthesis of cationic gemini imidazoline surfactants**

*3.3.1 Synthesis of imidazolines*

**Figure 5.**

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**Figure 6.**

*Quaternization of the Bisalkyl-bis-imidazoline intermediate [21].*
