Sequestering of As(III) and As(V) from wastewater using a novel neem leaves/MnFe₂O₄ composite biosorbent

Abstract

An arsenic biosorbent comprising neem leaves (NL) and MnFe2O4 particles was developed and its removal potential was investigated. Physicochemical analysis of the NL/MnFe2O4 composite (MNL) was performed for the Brunauer, Emmett and Teller surface area, Fourier transform infrared spectra (FT-IR), and scanning electron microscopy-Energy-dispersive X-ray (EDX). The following parameters were optimized: pH, biosorbent dose, contact time, temperature, and initial arsenic concentration. The optimum pH values achieved for biosorption of As(III) and As(V) were 7.0 and 4.0, respectively, when the equilibrium time was 110 minutes for both. MNL was found to be efficient with 85.217% and 88.154% biosorption efficiency at a concentration of 50 mg/L of As(III) or As(V) solution, respectively. This was also proved by the FT-IR study of arsenic-loaded biosorbent. For establishing the best suitable correlation for the equilibrium curves exploiting the procedure of the nonlinear regression for curve fitting analysis, isotherm studies were conducted for As(III) and As(V) using 30 isotherm models. The pattern of biosorption fitted well with Brouers-Sotolongo isotherm model for As(III) and Langmuir-Freundlich as well as Sips isotherm models for As(V). Dubinin-Radushkevich (D-R) isotherm studies specified that ion exchange might play a significant role. The influence of various co-existing ions at different concentrations was examined. Desorption study was performed using various concentrations of NaOH solution.

ADSORPTION OF As(III) FROM AQUEOUS SOLUTION ONTO IRON IMPREGNATED USED TEA ACTIVATED CARBON: EQUILIBRIUM, KINETIC AND THERMODYNAMIC STUDY

“…The effect of pH on the removal of As(III) by Fe-UTAC was examined at various pH values (3)(4)(5)(6)(7)(8)(9)(10)(11)(12) at 298 K with different concentrations of As(III) solutions. Temperature studies were carried out at 298, 308, 318 and 328 K at pH 8 with different concentrations of As(III) solutions.…”

“…The Richenberg model which differentiates between film and intraparticle diffusion and is given as follows: (9) where F is the fractional attainment of equilibrium at time t, and is obtained by the following expression; (10) B t is a mathematical function of X which can be evaluated from the equation given below:…”

“…Arsenic is carcinogenic and its long term exposure causes cancer of lungs, kidneys, liver, and skin. Generally, acute and chronic poisoning causes skin lesions, loss of appetite, muscular weakness, diabetes, gastrointestinal and cardiovascular diseases [9,10]. Naturally occurring arsenic in drinking water threatens the health and lives of people in many countries including Argentina, Chile, Mexico, China, Taiwan, Ghana, Hungary, Greece, Bangladesh, Vietnam, Poland, Canada, Japan, India, Iran and even in Pakistan [11,12].…”

The Role of Antioxidant Metabolism in Phytoremediation of Shrimp Farm Effluent by <i>Acrostichum </i><i>aureum </i><i>Linn</i>

“…Ammonia in water is the principal nitrogenous waste product excreted by aquatic animals and released from decomposing nitrogen containing organic matters by microbial activities. Rapid development of shrimp farming brings a series of environmental, human health and safety problems, as well as considerable profit and interests, thus causing concern about its sustainability [3,4]. Therefore; intensive culture of shrimps should properly managed to keep the shrimp cultivation sustainable.…”

Phytoremediation of arsenic-contaminated water: the role of antioxidant metabolism of Azolla caroliniana Willd. (Salviniales)

“…Among them, the use of aquatic plants, or phytoremediation, is an effi cient, viable and low-cost technology (Farnese et al 2014). Plants used in phytoremediation should be able to remove the pollutant from the environment and be tolerant to damage caused by it (Podder & Majumder 2016). One of the most damaging eff ects of As in plants is oxidative stress caused by an increase in the production of reactive oxygen species (ROS), which may alter the normal metabolism of plants and damage cell membranes, causing inhibition of photosynthesis and growth (Silveira et al 2015) and eventual cell death (Sharma et al 2012).…”