Bio-adsorbent derived from papaya peel waste and magnetic nanoparticles fabricated for lead determination

Abstract

Determination of toxic lead ions at trace level using solid-based adsorbents has become of interest in recent years. In this work, a novel bio-adsorbent originating from papaya peel waste (PPw) and magnetic nanoparticles (Fe 3 O 4 ) was developed (Fe 3 O 4 /PPw). The new adsorbent was prepared using a one-pot green method and characterized by Fourier transform infrared, X-ray diffractometer, energy-dispersive X-ray spectroscopy and field emission scanning electron microscopy. The synthesized Fe 3 O 4 /PPw was used as a magnetic solid-phase extraction (MSPE) sorbent for extraction of lead ions from waste water prior to assessing by flame atomic absorption spectroscopy. The parameters influencing extraction recovery, including desorption solvent, solvent volume, sample volume, extraction time, desorption time, adsorbent dosage, salt effect and pH were optimized. A linear response for the MSPE method was achieved at concentrations from 10 to 100 ng mL −1 with a good coefficient of determination (R 2 = 0.9987). Detection limits and quantitation limit of the MSPE method were observed around 2 ng mL −1 and 6.6 ng mL −1, respectively. The intraday and interday precision (%RSD) was in the range 1.6 %-4.5 % and 2.3 %-7.4 %, respectively. The recovery amounts obtained were 91 % for tap water, 85.9 % for river water and 86 % for waste water. The synthesized adsorbent showed a minimum reusability of eight cycles without significant change in the lead determination. The results proved that the new bio-adsorbent (Fe 3 O 4 /PPw) is potentially capable to extract the Pb(II) from aqueous media under optimum conditions with a high extraction efficiency.

Síntesis de nanopartículas de magnetita a partir del extracto de cáscara de papaya para la degradación de colorantes azoicos en soluciones acuosas

“…Uno de los grandes problemas ambientales que se da en los tiempos actuales está relacionado con el uso desmesurado del recurso hídrico, ya que este es de vital importancia para todos los procesos productivos; sin embargo, en algunos casos no es necesario que se haga uso de agua potable, por tal motivo es indispensable conocer nuevos métodos que además de ser ecológicos permitan la remoción de diferentes tipos de contaminantes, reduciendo así el gasto de agua y los costos de operación [1].…”

Greener synthesis of chemical compounds and materials

“…This adsorption process is exothermic, scalable and can be applied at natural water pHs. In addition, magnetic Fe 3 O 4 /PPw (PPw, papaya peel waste) bio-adsorbent, synthesized in one step from FeCl 2 · 4H 2 O and FeCl 3 · 6H 2 O as metal source by slow growth of Fe 3 O 4 nanoparticles on PPw, was used for Pb 2+ extraction from wastewater, allowing excellent lead determination and easy separation by an external magnet [202]. Other adsorbents in aerogel form will be shown below.…”

“…Also, iron-containing nano-impregnated adsorbent was prepared from ferrous sulfate as metal source, using black tea solution, heated at 80°C for 1 h and further sonication with 1-butyl-3-methylimidazolidium bromide solution for 24 h. Also, iron-containing nano-impregnated adsorbent was prepared from ferrous sulfate as metal source, using black tea solution, heated at 80°C for 1 h and further sonication with 1-butyl-3methylimidazolidium bromide solution for 24 h [201]. The formed material was applied for selective and fast fluoride removal from water (up to 90%, figure 25), whose mechanism is based on the difference in electronegativity of F − and Br − and includes interaction of its positive charges with fluoride anions [202]. Other adsorbents in aerogel form will be shown below.…”

Magnetic Covalent Organic Framework for Efficient Solid-Phase Extraction of Uranium for on-Site Determination by Portable X-ray Fluorescence Spectrometry

“…To expedite and simplify the analysis process, a novel generation of magnetic dispersive solid phase extraction (MDSPE) technique is rapidly emerging along with extractants possessing diverse magnetic properties . Magnetite (Fe 3 O 4 ) is commonly used to confer magnetic properties onto extractants, which can pursue other superior properties by modification with metal layered double oxides, silica, titania, biomaterials, carbon-based nanomaterials, metal–organic frameworks (MOF), among others. Covalent organic frameworks (COFs), an emerging class of porous organic frameworks, have been barged to the forefront of adsorbent materials, owing to their exceptional physical and chemical stability, abundant well-proportioned pores, large specific surface areas, rich functional groups, tunable chemical properties, and high adsorption capacity .…”