EFFECT OF TEMPERATURE ON THERMO PHYSICAL PROPERTIES OF BINARY LIQUID MIXTURE AND ITS EFFECT ON ENVIRONMENT. *K.Sathya

*K.Sathya 1 , R. Baskaran 2 and T. R. Kubendran 3 . 1. Department of Biotechnology, Rajalakshmi Engineering College, Chennai-602105. 2. Department of Chemical Engineering, St.Joseph’s College of Engineering, Chennai-600119. 3. Department of Chemical Engineering, A.C. Tech., Anna University, Chennai-600025. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History

Liquid mixtures have attracted considerable attention due to their unusual behaviour. In pharmaceutical, chemical and biochemical industries, organic compounds are used as an intermediate and are normally handled in fluid form and as a consequence, the transport properties of fluids assume importance due to their environmental impact. The emission of volatile or partially volatile compounds must be reduced to appropriate levels before exposing industrial streams to atmosphere. One of the most widespread technologies used to achieve that reduction is adsorption using suitable adsorbent like activated carbon in a fixed bed. These processes are operated at different temperatures. Design of such operations requires quantitative estimates of transport properties of liquid mixtures. In the present study, densities and viscosities of paraanisaldehydepropylacetate organic mixture was measured over the entire mole fractions at 308.15, 318.15 and 328.15 K. Studies on determination of different thermo physical properties of liquid mixtures within wide range of composition and temperature are valuable sources of information that might be used to examine relation between the internal structure of the system and its physical properties. Excess Gibbs free energy was obtained at different temperature from the measured properties and the spontaneity of the process was discussed. The impacts of organic compound, based on Gibbs free energy values were also discussed. The positive Gibbs free energy revealed that the adsorption is nonspontaneous and hence the impact on the environment of the binary liquid mixtures paraanisaldehyde -propylacetate is high at 308. 15

…………………………………………………………………………………………………….... Introduction:-
The organic compounds like paraanisaldehyde -propyacetate mixtures are widely used an intermediate in pharmaceuticals and agrochemicals industries. Paraanisaldehyde along with acid and ethanol is frequently used to stain thin layer chromatography plates (Saravanakumar et al., 2012a). The unused organic compounds are discharged as waste in effluent water. The removal of these organic compounds from waste water is essential before the stream are let out or recycled back. Adsorption process is recognized as one of the effective and low cost ISSN: 2320-5407 Int. J. Adv. Res. 4 (9), 926-933 927 technique for removal of organic pollutants from waste water, and produces high quality treated effluent (Rasheed 2013a). The present work discusses about the feasibility of the treatment of the above waste water at various temperatures based on excess Gibbs free energy of compounds. For the successful design and operation of adsorption process, the data on the thermo physical properties like density and viscosity of the organic liquid mixtures are important to establish. The feasibility studies of the adsorption process for organic liquid mixtures are essential before the adsorption process which involves the excess Gibbs energy calculation. Since no data is reported in the literature, the objective of the present study is to find out the feasibility of the process by estimating excess Gibbs free energy in terms of thermo physical properties like density and viscosity at various temperatures to conclude the impact on environment. Paraanisaldehyde is an organic compound that is a clear to slightly yellow oily liquid with strong aroma. Its molecular formula is C 8

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 Respiratory, allergic, or immune effects in infants are associated with man-made VOCs and other indoor or outdoor air pollutants. Health effects include eye, nose, and throat irritation; headaches, loss of coordination, nausea; and damage to the liver, kidney, and central nervous system. Some organics can cause cancer in animals; some are suspected or known to cause cancer in humans. Key signs or symptoms associated with exposure to VOCs include conjunctival irritation, nose and throat discomfort, headache, allergic skin reaction, dyspnea, declines in serum cholinesterase levels, nausea, vomiting, nose bleeding, fatigue, dizziness.  Many organic compounds are known to cause cancer in animals; some are suspected of causing, or are known to cause, cancer in humans (Huiping et al., 2014).  Short-term exposure to high levels of alkyl acetate results first in irritation of the eyes, nose and throat, followed by headache, nausea, vomiting, sleepiness, and unconsciousness. Very high concentrations may cause a stupor. Prolonged exposures may cause clouding of the eye, damage to the lung, heart, kidney and liver problems. Excess Gibbs free energy of binary mixture was obtained from the following equation ΔG E = RT [ln (η V)-(X 1 ln (η 1 V 1 )+X 2 ln (η 2 V 2 ))] (2) where, R is the universal constant of gases; T is the absolute temperature, V 1

Results and Discussion:-
Measured values of densities and viscosities of paraanisaldehyde-propyl acetate binary liquid mixture at different temperature are shown in Fig. 3, and 4. The result showed that the decrease in density and viscosity with temperature. It was due to more molecular interaction between the binary liquid mixture (Saravanakumar et al., 2012e;Saravanakumar et al., 2011). Effect of temperature on density and viscosity is considered important, because excess Gibbs free energy is mainly depend on these properties and is calculated from the measured experimental data.
Excess Gibbs free energy provides information about the molecular interactions and macroscopic behaviour of fluid mixtures which can be used to test and improve thermodynamic models for calculating and predicting fluid phase equilibrium (Mchaweh et al., 2004). The magnitude of excess Gibbs free energy represents the strength of interaction between unlike molecules (Riddick 1986 The effect of temperature on Excess Gibbs free energy for paraanisaldehyde-propyl acetate binary system is shown in Fig. 5, 6 and 7. Excess Gibbs free energy was found to be positive for all temperatures. The positive values of excess Gibbs free energy of binary mixture indicate the presence of specific and strong interactions in the systems (Ezekiel et al., 2012;Kondaiah and Krishna Rao 2013). Positive Gibbs free energy indicates the non-spontaneous nature of the process. A positive value of Gibbs free energy revealed that there was an energy barrier. When the ions enter from the solution into the particle surface, some of the water molecules forming hydration shell of ions were stripped off and simultaneously the degree of freedom of ions decreased. So feasibility of the process was reduced. Hence, the adsorption did not occur or adsorption will be endothermic in nature (Ayar et al., 2008). So treatment of these types of organic mixtures is not feasible at 308.15, 318.15 and 328.15 K. The impact of these compounds on environment could not be reduced easily due to non spontaneity nature or less feasibility.

Summaries:-
Hence, densities and viscosities for organic binary mixtures were measured experimentally at different temperature over wide concentration range. The effects of temperature on densities, viscosities and excess Gibbs free energies on mixture were reported in Fig.3, 4, 5, 6,7, 8 and 9. Positive Gibbs free energy indicates the non-spontaneous nature of the adsorption process involves in the treatment of effluent waste water. It revealed that the impact of paraanisaldehyde-propyl acetate binary system on environment would be high at 308.15, 318.15 and 328.15 K.