R. T. Vashi

Treatment of Textile Wastewaterby Adsorption and Coagulation

The composite of wastewater treatment was carried out using activated charcoal as adsorbent to remove COD, BOD, color in which various parameters like adsorbent dose, contact duration, temperature and agitator speed were considered. The adsorbent behavior can be explained on the basis of Freundlich and Langmuir adsorption isotherm model. Maximum removal (87.6, 81.0 and 90.0%) of COD, BOD and color respectively was found at adsorbent dosage of 11 g/L. Also, the textile mill wastewater was treated with different doses of coagulants like alum, ferric sulphate and ferrous sulphate at constant contact duration (4 hours) and room temperature (300 K). Percentage reduction (maximum) corresponds to 80.2, 74.0 and 84.9% was obtained for removal of COD, BOD and color respectively.

Adsorption of Crystal Violet Dye onto Tamarind Seed Powder

The present investigation describes adsorption of crystal violet dye from its aqueous solution onto tamarind (Tamarindus indica) fruit shell powder. Initial concentration, agitation speed and pH with various temperature have been studied, in which pH was found to be most effective. The adsorption data were mathematically analyzed using adsorption isotherm like Freundlich and Langmuir isotherm to study adsorption mechanism of crystal violet onto this seed powder. Freundlich isotherm was found to be most applicable. The equilibrium data were applied to intra-particle diffusion and adsorption kinetics. The reaction was found to be pseudo second order.

A comparison study of removal of methylene blue dye by adsorption on Neem leaf powder (NLP) and activated NLP

Abstract The adsorption of basic dye, Methylene Blue Dye (MBD) onto neem (Azadirachta indica) leaf powder (NLP) and activated NLP with sulphuric acid was compared in this investigation. The surface analyses of NLP and activated NLP (particle size distribution, porosity, pore volume, pore diameter and BET surface area) were conducted using sophisticated instrument. The process parameters like adsorbent dose, pH, temperature and contact duration have been studied. The experimental data were analyzed using Langmuir and Freundlich isotherm, in which adsorption capacities and intensities were evaluated. Three kinetic models, pseudo first-, second-order and Elovic equations were applied to describe the adsorption process, in which correlation coefficient for each kinetic equation were calculated and evaluated.

Synthesis, Spectroscopic Studies and Antifungal Activity of 2-((4(3-Chlorophenyl) piperazine-1-yl)methyl)-3-(8-hydroxy quinolin-5-yl)- 3( H)-quinazolin-4-one Ligand and its Chelates

The novel ligand HL6 was synthesized using anthranilic acid and it was undergo the chelating reaction with Cu(II), Ni(II), Co(II), Mn(II) and Zn(II) to prepare transition metal chelates. These chelates were characterized by physicochemical methods such as elemental analysis, conductometric studies, magnetic susceptibility, FT-IR, NMR and electronic spectra. The stoichiometry of the complexes has been found to be 1: 2 (Metal: ligand). An octahedral geometry around Co(II), Ni(II) and Mn(II), distorted octahedral geometry around Cu(II) and tetrahedral geometry around Zn(II) have been proposed. The antifungal activity of ligand and its metal chelates were conducted against various fungi.

Use of Naturally Prepared Coagulants for the Treatment of Wastewater from Dyeing Mills

The wastewater generated by the textile industry is rated as the most polluting among all industrial sectors considering both volumes discharged and effluent composition. The present investigation is intended for the removal of COD, BOD, and color from textile wastewater using naturally prepared coagulants, namely, Surjana seed powder (SSP), maize seed powder (MSP), and chitosan. The effects of coagulant dose, flocculation time, and temperature are studied. The sludge volume index (SVI) and turbidity are examined for their various effects. SSP is more effective than chitosan and MSP for the removal of COD and color, and chitosan is more efficient than SSP and MSP in terms of SVI and turbidity. Maximum percentage reduction corresponding to 75.6 and 62.8 is obtained for the removal of COD and color, respectively, using SSP.

Feasibility of Naturally Prepared Adsorbent

This chapter starts with the basic introduction of adsorption, its types, and its mechanism. Investigated different sorbents for batch and column treatment are tabulated with respective references. Isotherms for batch (Freundlich and Langmuir) and columns (Thomas, Yoon-Nelson, bed depth service time, and Adams and Bohart) are discussed. Feasibility and comparison of naturally prepared adsorbents, that is, neem ( Azadirachta indica ) leaf powder, guava ( Psidium guajava ) leaf powder, and tamarind ( Tamarindus indica ) seed powder, and their activated forms using different acids are determined using various sophisticated analytic facilities like Fourier transform infrared, particle size distribution, scanning electron microcopy, and surface area, porosity, pore diameter, and pore volume analyses and also adsorptive batch treatment on dye solution. Treatment data using Freundlich and Langmuir isotherm are analyzed and compared. It is concluded that activated neem leaf powder, activated guava leaf powder using sulfuric acid, and normal tamarind seed powder are more suitable than their investigated analog adsorbents for the adsorption process to remove dyes and other contaminations.

Characterization of Textile Wastewater

In this chapter, the collection, preservation, analysis method, and report of physicochemical and microbiological parameters of textile wastewater are mentioned. Principle, apparatus, interface, limitations, pretreatment, and procedure in short and detailed forms of 22 parameters are summarized. Water quality parameters are divided mainly into two parts: (i) titrimetric method [pollution-indicating parameters like chemical oxygen demand (COD) and biochemical oxygen demand (BOD), color, total hardness, magnesium hardness, and calcium hardness] and (ii) instrumentation parameters (pH, color, metals, etc.). The analysis report of 22 parameters for combined textile wastewater before treatment, collected from July 2009 to July 2010 bimonthly at GIDC Pandesara, Surat, Gujarat, is included. These parameters are compared with permissible limits of parameters for textile wastewater given by various firms including Central Pollution Control Board and US Environmental Protection Agency, which shows that COD and BOD values are 5 and 10 times, respectively, higher than limits. Characteristics of textile wastewater that were investigated and analyzed by different scientists are well fitted with one another. It shows that textile wastewater is highly polluted and treatment is necessary prior to discharge of it in environment.