Dispersive solid phase extraction of lead in water samples using embedded 1,5-diphenylcarbazone grafted graphene oxide in microporous magnetic chitosan coupled with flame atomic absorption spectrometry

Carbon and metal based magnetic porous materials - Role in drug removal: A Comprehensive review

Development of effective adsorbents for the removal of contaminants from wastewater is indispensable due to increasing water scarcity and a lack of pure drinking water, which are prevailing as a result of rapid industrialization and population growth. Recently, the development of new adsorbents and their effective use without generating secondary waste is receiving huge consideration. In order to protect the environment from primary and secondary pollution, the development of adsorbents from wastes and their recycling have become conventional practices aimed at waste management. As a result, significant progress has been made in the synthesis of new porous carbon and metal-organic frameworks as adsorbents, with the objective of using them for the removal of pollutants. While many different kinds of pollutants are produced in the environment, drug pollutants are the most vicious because of their tendency to undergo significant structural changes, producing metabolites and residues with entirely different properties compared to their parent compounds. Chemical reactions involving oxidation, hydrolysis, and photolysis transform drugs. The resulting compounds can have detrimental effects on living beings that are present in soil and water. This review stresses the development of adsorbents with adjustable porosities for the broad removal of primary drug pollutants and their metabolites, which are formed as a result of drug transformations in environmental matrices. This keeps adsorbents from building up in the environment and prevents them from becoming significant pollutants in the future. Additionally, it stops secondary pollution caused by the deterioration of the used adsorbents. Focus on the development of effective adsorbents with flexible porosities allows for the complete removal of coexisting contaminants and makes a substantial contribution to wastewater management. In order to concentrate more on the development of flexible pore adsorbents, it is crucial to comprehend the milestones reached in the research and applications of porous magnetic adsorbents based on metal and carbon, which are discussed here.

Preconcentration and Removal of Pb(II) Ions from Aqueous Solutions Using Graphene-Based Nanomaterials

Direct determination of lead trace concentration in the presence of relatively complex matrices is often a problem. Thus, its preconcentration and separation are necessary in the analytical procedures. Graphene-based nanomaterials have attracted significant interest as potential adsorbents for Pb(II) preconcentration and removal due to their high specific surface area, exceptional porosities, numerous adsorption sites and functionalization ease. Particularly, incorporation of magnetic particles with graphene adsorbents offers an effective approach to overcome the separation problems after a lead enrichment step. This paper summarizes the developments in the applications of graphene-based adsorbents in conventional solid-phase extraction column packing and its alternative approaches in the past 5 years.

Engineered Magnetic Carbon-Based Adsorbents for the Removal of Water Priority Pollutants: An Overview

This review covers the preparation, characterization, and application of magnetic adsorbents obtained from carbon-based sources and their application in the adsorption of both inorganic and organic pollutants from water. Different preparation routes to obtain magnetic adsorbents from activated carbon, biochar, hydrochar, graphene, carbon dots, carbon nanotubes, and carbon nanocages, including the magnetic phase incorporated on the solid surface, are described and discussed. The performance of these adsorbents is analyzed for the removal of fluoride, arsenic, heavy metals, dyes, pesticides, pharmaceuticals, and other emerging and relevant water pollutants. Properties of these adsorbents and the corresponding adsorption mechanisms have been included in this review. Overall, this type of magnetic adsorbents offers an alternative for facing the operational problems associated to adsorption process in water treatment. However, some gaps have been identified in the proper physicochemical characterization of these adsorbents, the development of green and low-cost preparation methods for their industrial production and commercialization, the regeneration and final disposal of spent adsorbents, and their application in the multicomponent adsorption of water pollutants.

Application of polysaccharide biopolymers as natural adsorbent in sample preparation

Preparing samples for analyses is perhaps the most important part to analyses. The varied functional groups present on the surface of biopolymers bestow them appropriate adsorption properties. Properties like biocompatibility, biodegradability, presence of different surface functional group, high porosity, considerable absorption capacity for water, the potential for modification, etc. turn biopolymers to promising candidates for varied applications. In addition, one of the most important parts of determination of an analyte in a matrix is sample preparation step and the efficiency of this step in solid phase extraction methods is largely dependent on the type of adsorbent used. Due to the unique properties of biopolymers they are considered an appropriate choice for using as sorbent in sample preparation methods that use from a solid adsorbent. Many review articles have been published on the application of diverse adsorbents in sample preparation methods, however despite the numerous advantages of biopolymers mentioned; review articles in this field are very few. Thus, in this paper we review the reports in different areas of sample preparation that use polysaccharides-based biopolymers as sorbents for extraction and determination of diverse organic and inorganic analytes.