INTERNATIONAL JOURNAL OF CIVIL 17 19, July ENGINEERING 2014, Mysore, Karnataka, India AND TECHNOLOGY (IJCIET) ISSN 0976 6308 (Print) ISSN 0976 6316(Online) Volume 5, Issue 9, September (2014), pp. 79-84 IAEME: www.iaeme.com/ijciet.asp Journal Impact Factor (2014): 7.9290 (Calculated by GISI) www.jifactor.com IJCIET IAEME COLOR REMOVAL FROM TEXTILE WASTEWATER USING CuO NANO- PARTICLE COATED ON SAND, CINDER AND GAC 1 B M Krishna, 2 B M Nagabhushana, 3 Anitha S, 4 Sahana M 1 Associate Professor, Department of Environmental Engineering, SJCE, Mysore, Karnataka, India 2 Professor, Department of Chemistry, M S R I T, Bangalore, Karnataka, India 3 M.Tech., Department of Environmental Engineering, SJCE, Mysore, Karnataka, India 4 B.E., Department of Environmental Engineering, SJCE, Mysore, Karnataka, India ABSTRACT In this research, batch adsorption studies were carried out using CuO nano-particles coated on the surface of different adsorbents like graded sand, cinder and granular activated carbon (GAC) by Low temperature pyrolysis (LTP) method for color removal from textile wastewater. Uncoated and CuO coated adsorbent doses were varied from 1 40 g/l with stirring time of 20 min and stirring speed of 400 rpm. Results showed that CuO coated adsorbents showed increase in the color removal efficiency than uncoated adsorbents and LTP method was seen to be more successful on GAC than cinder and sand. Keywords: Cinder, Copper Oxide, GAC, Graded Sand, Textile Wastewater. 1. INTRODUCTION Many industries use dyes to color their products such as textile manufacturing, leather tanning, cosmetics, paper, food processing, and pharmaceutical industries and also consume substantial volumes of water. The presence of small amounts of dyes in water is highly visible and undesirable. Adsorption techniques have proved to be an effective and attractive process for removal of non-biodegradable pollutants (including dyes) from wastewater [1]. The annual production of synthetic dyes and dying stuffs are generally exceeding 700,000 tones. Generally, more than 100,000 commercial dyes are produced every year for the sake of industrial applications [2]. About 2 50% of the dyestuffs quantity is released into the ecosystem as generated industrial wastewater due to various applications of basic and reactive dyes. However, this subject represents a major environmental problem due to environmental impact on the quality of water. 79
Reactive dyes are used in the textile industry as the largest group of dying materials for cellulose and cotton fibers. These are characterized by high water solubility, non-biodegradability and low adsorption ability onto the biomass. Reactive dyes are known for their low degree of fixation on the textile surface and thus the generated industrial wastewaters are highly colored in nature [3]. Metal oxide (MO) nano-particles have been attracting much attention not only for fundamental scientific research, but also for various practical applications because of their unique physical and chemical properties. These physical and chemical properties are strongly dependent on the sizes, shapes, compositions, and structures of the nano-particles. CuO nano-structures with large surface areas and potential size effects possess superior physical and chemical properties that remarkably differ from those of their micro or bulk counterparts [4]. Recent studies have demonstrated that nanoscale CuO can be used to prepare various organic inorganic nanocomposites with high thermal conductivity, high electrical conductivity, high mechanical strength, hightemperature durability [5]. The nanoscale CuO is an effective catalyst for CO and NO oxidation as well as in the oxidation of volatile organic chemicals such as methanol. CuO nanostructures are also extensively used in various other applications, including gas sensors, bio-sensors, nanofluid, photodetectors, energetic materials (EMs), field emissions, supercapacitors, removal of inorganic pollutants, photocatalysis and magnetic storage media. The superhydrophobic properties of CuO nanostructures render these materials as promising candidates in self-cleaning coatings (antibiofouling), surface protection, textiles, water movement, microfluidics, and oil water separation. Compared with other MO nanostructures, such as TiO 2, ZnO, WO, and SnO 2, CuO nanostructures have more interesting magnetic and super hydrophobic properties [6]. 2. MATERIALS AND METHODS Raw textile wastewater samples were collected from KSIC, Mysore. Table 1 shows physicochemical parameters of raw textile wastewater characterized as per standard methods. Table 1: Characteristics of Textile wastewater Parameter Value COD 2616 mg/l Nitrate 159.8 mg/l Phosphate 253.3 mg/l Sulphate 205.4 mg/l ph 5.44 Conductivity 2701 µs/cm Total Hardness 120 mg/l Calcium Hardness 80 mg/l Magnesium Hardness 40 mg/l Cupric nitrate trihydrate was used as coating material on graded sand, cinder and industrial grade granular activated carbon (GAC) by Low temperature pyrolysis (LTP) method. Cupric nitrate trihydrate was weighed and dissolved in distilled water on a petridish to which weighed amount of sand, cinder and GAC were added separately. The dish was kept in a muffle furnace preset to the temperature of 200 C for approximately 2 hours. After pyrolysis the coated material was washed with water and weighed to know the amount of material coated. Batch experiments were carried out in the laboratory for uncoated and coated sand, cinder and GAC for different adsorbent dose. 50 ml of real wastewater was contacted with different dosages of adsorbent in conical flasks of 100 ml capacity. The conical flask containing real 80
wastewater and adsorbent was agitated at 400 rpm using a magnetic stirrer for a pre-optimized contact time of 20 mins. After each experiment, the samples were centrifuged and analyzed for absorbance using spectrophotometer in wavelength range of 190 800 nm, the percentage color removal was then calculated. 3. RESULTS AND DISCUSSION Fig. 3.1 shows raw cinder and CuO coated cinder of size 1.18 0.6 mm. Fig. 3.2 shows percentage color removal as a function of adsorbent dose (CuO coated Cinder 1.18-0.6 mm). Fig.3.1: Uncoated and CuO coated cinder Fig.3.2: Color removal by cinder (1.18 0.6mm) before and after coating with CuO The adsorbate adsorbent system was contacted for duration of 20 min at agitation speeds of 400 rpm. At smaller adsorbent dose (2 20 g/l), showed slow removal was observed. At higher adsorbent doses of > 20 mg/l showed higher color removal of about 45%. Uncoated GAC showed 81
reduction in color removal with increase in the adsorbent dose due to magnetic properties of cinder. CuO coated cinder showed optimal color removal of 45% for 36 g/l. Fig.3.3: Uncoated and CuO coated sand Fig. 3.3 shows raw graded sand and CuO coated sand. Fig. 3.4 shows percentage color removal as a function of adsorbent dose (CuO coated sand). Sand coated with 0.5 g cupric nitrate and sand coated with 2 g cupric nitrate were used to check the color removal and the maximum color was removed from 2 g CuO coated cinder compared to 0.5 g CuO coated cinder. Fig. 3.5 shows comparison of color removal by coated sand and cinder which shows that sand removes more color compared to cinder. Fig.3.4: Color removal by graded sand before and after coating with CuO. 82
Fig.3.5: Comparison of color removal by CuO coated cinder and graded sand. Fig.3.6: Color removal by GAC 1.18 0.6 mm (before and after coating). Fig.3.6 shows color removal by GAC of size 1.18 0.6 mm which showed 100% color removal for CuO coated GAC of dosage 16 g/l with contact time 20 min. 83
4. CONCLUSION LTP method was seen to be more successful on GAC than cinder and sand. Maximum color removal was achieved by smaller particle size (1.18 0.6 mm) because of more surface area available for adsorption, compared with 2.36 1.18 mm. CuO coated adsorbents showed increase in the color removal efficiency than uncoated adsorbents. It was found that the rate controlling step for removing color from real wastewater by using CuO coated GAC was intra particle diffusion. Real wastewater showed promising results than synthetic wastewater by approximately 30% when CuO coated adsorbents were used. 5. REFERENCES 1. R. Han, Y. Wang, W. Zou, Y. Wang, J. Shi, Comparison of linear and nonlinear analysis in estimating the Thomas model parameters for methylene blue adsorption onto natural zeolite in fixed-bed column, Journal of Hazardous Materials, 145, 2007, 331 335. 2. G. Moussavi, M. Mahmoudi, Removal of azo and anthraquinone reactive dyes from industrial wastewaters using MgO nanoparticles, Journal of Hazardous Materials, 168, 2009, 806 812. 3. G. M. Nabil, N. M. El-Mallah, M. E. Mahmoud, Enhanced decolorization of reactive black 5 dye by active carbon sorbent-immobilized-cationic surfactant (AC-CS), Journal of Industrial and Engineering Chemistry, 17, 2013, 83 89. 4. S. Anandan, S. Yang, Emergent methods to synthesize and characterize semiconductor CuO nanoparticles with various morphologies - an overview, Journal of Exp Nanoscience, 2, 2007, 23 56. 5. Q. Zhang, K. Zhang, D. Xu, G. Yang, H. Huang, F. Nie, C. Liu, S. Yang. CuO nanostructures: Synthesis, characterization, growth mechanisms, fundamental properties, and applications, Journal of Progress in Materials Science, 60, 2014, 208 337. 6. D.P. Singh, N. R. Neti, A. Sinha, O. N. Srivastava, Growth of different nanostructures of Cu 2 O (nanothreads, nanowires, and nanocubes) by simple electrolysis based oxidation of copper, Journal of Physical Chemistry, 111, 2007, 1638 45. 84