INTRODUCTION

Nanotechnology is one of the emerging multidisciplinary research areas. The various types of nanoparticles, such as micelle, metallic nanoparticles, nanotubes, and polymeric nanoparticles, have been reported [1,2]. The design of different nanoparticles and their applications is one of the best utilizations of nanotechnology. The synthesis and application of surfactant can be a homogenous catalysis reaction for waste water treatment [3-6]. Surfactants are usually organic compounds which contain both hydrophobic group (tails) and hydrophilic group (heads). Surfactants are used in lubricants as an ingredient, such as shaving creams, and also in car engine lubricants, which helps to keep particles away from the engine parts. Surfactants are used as cleaning agents and help cleaning agents to remove dirt from the surface being cleaned [2]. Surfactant can be non-ionic, anionic and cationic and their synthesis depends on the utilization. Very few studies have been reported the synthesis of biodegradable cationic surfactant and their applications for the dye removal study [5]. This lead to the synthesis of the sebacic acid-derived micelle and monomeric surfactants by esterification of the halogenated carboxylic acid with short-chain fatty alcohols or acids with 2-chloroethanol forming suitable esters such as 2-propylbromoacetate, 2-butybromoacetate, 2-octylbromoacetate, 2-chlorobenzoacetate, 2-chloromethylcinnamate, followed by their subsequent treatment with different spacers (4,4-trimethylenedipyridine, 1-methylimidazole). The identification of these surfactants is based on surface tension study [1-6]. A series of parameters such as the chemical structure of the surfactants, surface tension, critical micelle concentration (CMC), viscosity, density, conductance and pH are also determined. The synthesized ionic liquids are also applied for the dye removal from the water but the cost of ionic liquids is the main drawback to commercialize this process [5-9]. Textile dyes are extensively used in many manufacturing processes in the textile industry, but it has been proved that these dyes are very harmful to human health as well as for the environment [1,8,10]. The chemicals which are used during the preparation of dyes like azo dyes may cause carcinogenic effects [2,7]. The discharge of these dyes into water bodies have very toxic effects on aquatic animals and humans [2]. The dye molecules have a shape like narrow strips of paper,that is having length and breadth but relatively little thickness [1,2]. Basically, dyes are the compounds that are used to impart colour to the fabric and on any surface shells. Nowadays, the decolourization of wastewater from textile and other manufacturing industries is a major issue [3] because dyes are water-soluble compounds, and they impart very intense colour into the water as well as it makes the water acidic and the second reason is, they have great affinity of the dye to the fibre due to forces of attraction [4]. Main reason behind higher morbidity rates of kidney, liver, bladder cancers, etc. is the discharge of organic contaminants from various industries such as electroplating, textile production, and cosmetics [4-6,9].

HARMFUL EFFECTS OF DYES

Textile dyes are extensively used in many manufacturing processes in the textile industry, but it has been proved that these dyes are very harmful to human health as well as for the environment. The chemicals which are used during the preparation of dyes like azo dyes may cause carcinogenic effects. The discharge of these dyes into water bodies have very toxic effects on the variety of organism such as aquatic animals [8-12]. Dyes cause so many skin irritation, itchy or blocked nose, sneezing, and sore eyes. Synthetic dyes, such as reactive, vat, and disperse dyes, are skin sensitive [13]. Textile effluents contain so many organic and inorganic compounds [14]. During the process of dyeing, the total dye is not fixed on the fabric; some of the portions remain unfixed to the fabric and get washed out. This unfixed dye content is considered as textile effluent [15]. There are so many treatments used to treat this water, such as primary, secondary, and tertiary treatment processes like flocculation, trickling filters, and electrodialysis, etc. But these treatments are not effective for dye removal and for chemical removal. [16,17]. Due to their demerits, it is gaining interest to remove dye from wastewater by using different methods [9-12]. Organic compounds in wastewater, such as dyes and pigments in industry effluents, are toxic or have a lethal effect on aquatic living and humans as already discussed earlier [5,10-13]. Stability of organic contaminants, especially methyl blue, methyl red and methyl orange, to light, heat, or oxidizing agents makes them difficult to remove by various conventional wastewater treatments (chemical and biological) [10-15]. Decolourization is done by using methods such as Adsorption, Filtration, Precipitation, Degradation, Photodegradation, Chemical degradation etc [11-13]. This article is focused not only for the synthesis of biodegradable cationic surfactant but also to its utilization to remove organic dye.

The new sebacic acid-based cationic surfactant has excellent potentials for adsorptive removal of organic dyes and other organic ingredients for water remediation application. The Methyl red dye is chosen as model representative organic pollutants for efficient adsorptive removal from the simulated industrial wastewater using the new Gemini cationic surfactant adsorbent. The work reports an excellent adsorbent for the fast and efficient removal of organic dyes from industrial wastewater. This process of dye removal can be a pre-treatment step for dye effluent treatment to make useful waste for irrigation and other purposes.

EXPERIMENTAL SECTION

Chemicals and materials

Sodium hydroxide (NaOH), hydrochloric acid (HCl), concentrated sulphuric acid (H₂SO₄), Sebacic acid (C₁₀H₁₈O₄), NaCl and KCl analytical grade were purchased from E. Merck, India and used as received. Amyl alcohol (3-methyl butan-1-ol), decanol, benzyl alcohol, methyl benzoate, octanol, ethyl acetate, Ethanol - (C₂H₅OH), acetone (CH₃COCH₃) and toluene (C₇H₈) were obtained from S.D. fine chemicals. Methyl red dye is collected from Merck.

Preparation of dye solutions

1g.L^-1 stock solution of dyes was prepared by dissolving the appropriate amount of dye in water and stored in bottles. The solution was diluted by adding a suitable amount of water to the stock solution as per requirement.

Preparation of surfactant

Surfactants are prepared by the use of long-chain fatty acid and halo-alcohol and by the addition of a small amount of sulphuric acid (Figure 1). After the addition, stirred this solution for near about 72 h by the use of magnetic stirrer at 60°C. After that, add a pinch of (0.1 M) 4,4,4-triethylenedipyridene then again stirred this solution for near about 24 h. Then washed this solution with chloroform in separating funnel. The bottom layer is collected as a surfactant from separating funnel. The methodology described in scheme 1 (Figure 2) for dye removal study and separation of surfactant.

Instrumentation

The dye concentration before and after extraction was carried out by using shimadzo-1900 spectrophotometer. The dyes were analyzed at their respective λ_max. The dye concentrations removed was calculated from the absorbance of the initial and treated dye solution.

The instrument used for analysis of refractive index and density of the liquid sample was Rudolf analytical instrument (DDM2911). Rudolf research analytical instrument (DDM2911) was used for the analysis of density and refractive index of the liquid sample (red dye mixture and synthesized cationic surfactant).

The pH measurements were performed using a pH meter (ELICO model LI-127, India). The surface tension of synthesized micelle is measured using the Kyowa interface science surface tensiometer (Dy-300 model). The instrument was calibrated with deionized water, and 2-3 mL of sample was used for each test.

Experimental setup

For the preparation of surfactant, a simple Magnetic Stirrer were used. The speed of the stirrer was measured accurately in rpm. Then a separating funnel is used to separate the aqueous and solvent by gravity.

After the preparation of surfactant, it was used to remove dye from the waste water of dye. A particular solvent which is cost effective, is used in the reverse micelle extraction process. Solvent is separated from aqueous phase and solvent dispersion in the spreading in the appearance of surfactant. There are so many solvents such as amyl alcohol, butanol, methyl benzoate, ethyl acetate, octanol and decanol etc. are used for the elimination of dye in the reverse miceller extraction process. Among these solvents’ amyl alcohol has been found the best out of all other solvents for the removal of dyes in reverse miceller extraction process. The formation of reverse micelles occurs in the solvent phase. Amyl alcohol is easily soluble into water at room temperature and pressure. The time taken to separate a 100ml of the mixture of amyl alcohol is usually 2-5 h if kept within a range of surfactant concentrations [18,19].

RESULTS AND DISCUSSION

The physical properties of the synthesized micelle are described in Table 1. The sebacic acid derived liquid surfactant with a density of 1.35 g/cm² having a surface tension of 28 mN/m and a pH 1. We have shown the comparative study of physicochemical properties of synthesised cationic surfactant (sabacic acid based) with the reported cationic surfactant in detailed (Figure 3 and Table 2). Physico-chemical property of dye before treating with surfactant and after treating with surfactant is shown in Table 3. The red dye sample with a pH of 1 before treatment with a surfactant exhibit refractive index of 1.33 and a density of 1.35g/cm² at a temperature of 25°C. While the same dye after treatment with a surfactant becomes less acidic (pH 3) and colourless, and the density of the dye decreases to 1 g/cm² and refractive index increase up to 1.69 at the constant temperature of 25°C.

The adsorption reaction using micelle to demonstrate the effect of synthesized cationic surfactant to remove the organic dye (Methyl red), was performed at a different time on stream (2-24 h). The experiments also carried out at Methyl red dye to synthesized surfactant (adsorbent) with the addition of Tween 20, non-ionic surfactant. Tween 20 is a non-ionic hydrophobic surfactant, which is polyethoxylated sorbitol ester. It can act as wetting agent, dispersant and solubilizer [17-22]. The U.V result of reactant (Methyl red dye) shows absorbance at 500 nm wavelength before reaction with micelle. The absorbance of dye mixture after treating with sebacic acid derived micelle did not offer any absorbance at 500 nm. At 2 h of reaction, absorbance reported 3.9 ml at the U.V. range using 4 ml cationic surfactant in 100 ml dye solution. It concludes that after adding cationic surfactant (2 ml) and 8 ml non-ionic surfactant (Tween 20) and 10 amyl alcohol in the water sample no change in absorbance. It shows after adding cationic surfactant (6 ml) and 4 ml non-ionic surfactant (Tween 20) and 10 amyl alcohol in the dye sample, the absorbance shifted to UV region. The absorbance showed 0.039 in the UV region after 24 h of separation.

Figure 4 demonstrates the UV results of Methyl red dye after adsorbing on the cationic surfactant with different concentrations. The Methyl red dye mixture shows the absorption peak at 500nm wavelength with sharp intensity (Figure 4-Graph 1) which is not observed after adsorption reaction with cationic surfactant (Figure 4-Graph 2, 3 and 4). The minor absorption peaks reported at 200 nm in the dye mixture after adsorption on surfactant, which may be due to the presence of choloro ethanol and amyl alcohol. These results showed that synthesized cationic surfactant has a positive effect of removing the organic dye.

Table 4 shows the comparative study for the removal of dye removal using different techniques reported in the literature. Various techniques such as adsorption oxidation degradation and photochemical reaction was reported in this manuscript. We have done the adsorption study of methyl red dye using sebacic acid derived surfactant to remove dye. Photo catalytic method to remove dye was reported to be 92% dye removal capacity using Titanium based catalysts [23]. The methyl red dye removal study using Fenton reagent with CrK (SO₄)₂ salt reported 57% dye removal capacity [23-26]. The adsorption of dye using cationic surfactant (sabacic acid derived) was found to be more suitable (96% dye removal) than the other reported techniques. It is a good example of a homogenous catalysis reaction as a surfactant can act as a homogenous catalyst, and its application for wastewater treatment at atmospheric conditions. At the end of the reaction, the dark colour dye can be visualized and can be separated using the solvent extraction method. Figure 5 shows the decolourization of the dye sample after treating it with synthesized micelle.

CONCLUDING REMARKS

This work systematically demonstrates the synthesis of sebacic acid derived micelle using 4,4,4-triethylenedipyridene, inorganic-organic polymer complex stabilizing agent. The plausible mechanism of synthesises describes the ester formation initially to form biodegradable cationic surfactant. The application of surfactant studied for the dye removal by adsorption mechanism. The U.V. spectroscopic results show adsorption potential of dye after treating of surfactant with dye mixture at room temperature. The decolourization of Methyl red dye with micelle also shows the positive adsorption process. The Methyl red dye showed significantly higher adsorption on the synthesized cationic surfactant compared to nonionic surfactant (tween 20) under identical experimental conditions. The lower surface tension of micelle (28 mN/m) and no peak observation in the U.V analysis of the dye mixture after adsorbing on sebacic acid derived micelle shows the potential of synthesized micelle to remove dye sample.

ACKNOWLEDGMENT

P.K. thanks RIMT University for M.Phil. S.K. acknowledges RIMT University for Ph.D. We thank CSIR-CSIO, Chandigarh, for surface tension analysis.

1.   Yu D, Wang H, Yang J, Niu Z, Lu H, et al. (2017) Wastewater clean-up by graphene composite paper for tailorable supercapacitors. ACS Appl Mater Interfaces: 9: 21298-21306.

2.   Shannon MA, Bohn PW, Elimelech M, Georgiadis JG, Marinas BJ, et al. (2008) Science and technology for water purification in the coming decades. Nature: 245: 301-310.

3.   Ho YS, Chiang CC (2001) Sorption studies of acid dye by mixed sorbents. Adsorption 7: 139-147.

4.   Samanta AK, Konar A (2011) Dyeing of textiles with natural dyes.

5.   Reid R (1996) Go Green-a Sound Business Decision (part I). J Soc Dyers Colour 112: 103.

6.   Crini G (2006) Non-conventional low-cost adsorbents for dye removal: A review. Bioresour Technol 97: 1061-1085.

7.   Forgacs E, Cserhati T, Oros G (2004) Removal of synthetic dyes from wastewater: A review. Environ Int 30: 953-971.

8.   Muthuchamy M, Selvakumar N (2004) Studies on the effect of inorganic salts on the decoloration of acid dye effluents by ozonation. Dye Pigment 62: 221-228.

9.   Ong ST, Lee CK, Zainal Z (2007) Removal of basic and reactive dyes using ethylene diamine modified rice hull. Bioresour Technol 98: 2792-2799.

10. Khatib SK, Bullon J, Vivas J, Bahsas A, Oballos YR, et al. (2019) Synthesis, characterization, evaluation of interfacial properties and antibacterial activities of dicarboxylateanacardic acid derivatives from cashew nut shell liquid of Anacardium occidentale L. J Surfactants Deterg.

11. Khare SK, Srivastava RM, Panday KK, Singh VN (1989) Removal of basic dye (crystal violet) from waste water using wollastonite as adsorbent. Environ Technol 10: 785.

12. Katheresan V, Kansedo J, Yon Lau S (2018) Efficiency of various recent wastewater dye removal methods: A review. J Environ Chem Eng 6: 4676-4697.

13. Lu Z, Chu W, Tan R, Tang S, Xu F, et al. (2017) Facile synthesis of β-SrHPO4 with wide applications in the effective removal of Pb2+ and Methyl Blue. J Chem Eng Data 62: 3501-351.

14. Elliott A, Hanby WE, Malcolm BR (1954) The near infra-red absorption spectra of natural and synthetic fibres. J Appl Phys 5: 377.

15. Hassaan MA, Nemr A EL (2017) Advanced oxidation processes for textile wastewater treatment. Int J Photochem Photobiol 2: 85-93.

16. Liu L, Gao ZY, Su XP, Chen X, Jiang L (2015) Adsorption removal of dyes from single and binary solutions using a cellulose-based bioadsorbent. ACS Sustain Chem Eng 3: 432-442.

17. Hassaan MA, Nemr A EL, Madkour A (2016) Application of ozonation and U.V. assisted ozonation for decolorization of direct yellow 50 in sea water. Pharm Chem J 3: 131-138.

18. Pandit P, Basu S (2002) Removal of organic dyes from water by liquid-liquid extraction using reverse micelles. J Colloid Interface Sci 245: 208-214.

19. Pandit P (2004) Removal of ionic dyes from water by solvent extraction using reverse micelles. Environ Sci Technol 38: 2435-2442.

20. Gupta K, Khatri OP (2017) Reduced graphene oxide as an effective adsorbent for removal of malachite green dye, plausible adsorption pathways. J Colloid Interface Sci 501: 11-21.

21. Mondal S, Rana U, Das P, Malik S (2019) Network of polyaniline nanotubes for wastewater treatment and oil/water separation. ACS Appl Polym Mater 7: 1624-1633.

22. Patist A, Bhagwat SS, Penfield KW, Aikens P, Shah DO (2000) Measurement of critical micelle concentrations of pure and technical-grade nonionic surfactants. J Surfactants Deterg 3: 53-58.

23. De Brito-Pelegrini NN, De tarsoferreira sales P, Pelegrini RT (2007) Photochemical treatment of industrial textile effluent containing reactive dyes. Environ Technol 28: 321-328.

24. Ashraf S, Rauf MA, Alhadrami S (2006) Degradation of Methyl red using Fenton’s reagent and the effect of various salts. Dye and Pigments 69: 74-78.

25. Santhi T, Manomani S, Samitha T (2010) Removal of Methyl Red from aqueous solution by activated carbon prepared from the Annonasqumosa seed by adsorption. Chem Eng Res Bulletin 14: 11-18.

26. Gupta K, Khatri OP (2017) Reduced graphene oxide as an effective adsorbent for removal of malachite green dye: Plausible adsorption pathways. J Colloid Interface Sci 501: 11-21.