Browsing by Author "Jayarathna, I.P.L."
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Item Hardness Removal from Drinking Water Using Inorganic Ion Exchange Resin- Zeolite(Uva Wellassa University of Sri Lanka, 2019-02) Jayangani, K.C.; Weerasooriya, R.; Premachandra, N.P.; Jayarathna, I.P.L.The hardness of drinking water has become a major environmental problem at present and it has to be removed using cost effective technologies. This research focuses on using synthesized inorganic zeolite as an inorganic ion exchange resin for hardness removal. It is to be achieved by controlling the physical parameters on performance of zeolite in different hardness level of water. The research approach includes both batch and column experiments performed in laboratory condition to determine optimum level of zeolite on the removal process of Ca2+ and Mg2+ from water. A Batch contact time experiment was carried out with varying contact time for 10 g L-1 of a constant adsorbent mass at the concentration of 250 ppm for both Ca2+ and Mg2+. One hour was the optimum time. Accordingly, the experiment was carried out by varying adsorbent mass for different hardness level of Synthetic Hard Water (SHW). The different hardness level of water samples was reduced by 80-95% from 3-5 g dosage of zeolite. The data obtained from the batch adsorption system is not applicable for design a continuous adsorption system. Then, column sorption studies were carried out using fixed bed column, which was filled with sand and zeolite, mixed in 1:1. The influent flow rate and concentration of the SHW solution were kept constant at 12.7 mL min-1 and 100 ppm, respectively. The column was reached exhaustion after the 30 min, according to the breakthrough curve for the column. According to results, it can be concluded that synthetic inorganic zeolite can be used to remove hardness from all the hardness range of moderately hard water, hard water and very hard water in high percentage (80-95%).Item Synthesis and Characterization of Nano Zeolite-A (LTA Zeolites) With Aid of Sodium Dodecyl Sulfate (SDS) as Particle SizeControlling Agent(Uva Wellassa University of Sri Lanka, 2019) Kannangara, D.I.S.; Jayawardhana, B.A.Y.B.; Pitawala, H.M.J.C.; Weerasooriya, S.V.R.; Jayarathna, I.P.L.The conventional synthetic zeolites historically known as molecular sieves are crystalline aluminosilicates with well-defined pores. Nano zeolite-A synthesis has received considerable attention in the past decade and has today turned into essential in commercial materials. Usually, LTA zeolites (Linde Type A) are synthesized via low-temperature hydrothermal crystallization in the presence of the structure directing agents, known as “organic templates”. Generally, Tetramethylammonium-hydroxide will be used as a template. However, these templates are expensive and non-recyclable. Therefore, under the green chemistry point of view, numerous efforts have been devoted to synthesize template free LTA type nano zeolites. In this work, nano Zeolite-A was synthesized via both hydrothermal and microwave methods in the absence of organic templates. Instead of them, an anionic surfactant called Sodium dodecyl sulfate (SDS) was used for controlling the particle size. The effect of different crystallization conditions such as aging time, reaction time and temperature for changing properties such as particle size, morphology were investigated. The final products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and Fourier-transform infrared spectroscopy (FTIR) techniques. The obtained SEM and XDR results showed that both methods have produced pure LTA zeolites crystals with a 300 - 500 nm range in size with a high degree of crystallinity. In addition, the absence of characteristic zeolitic water peaks proved the synthesized compound was in dehydrated form. Compared to the hydrothermal method microwave approach is effective because it requires less reaction time and no any considerable change observed in crystal size and crystallinity. Therefore, surfactant based zeolite-A synthesis would be potentially important in the chemical industry due to its competitive advantages as a green approach and cost-effectiveness.