Abstract
Lead pollution in drinking water is one of the most common problems worldwide. In this research, sulfur and iron dual-doped mesoporous carbons are synthesized by soft-templating with sulfur content 4.4–6.1 atom% and iron content 7.8–9 atom%. Sulfur functionalities of the carbons are expected to enhance the affinity of the carbon toward lead whereas iron content is expected to separate the carbon from water owing to its magnetic properties. All the carbons were characterized by pore textural properties, x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive x-ray (EDX). In order to study the Pb(II) removal efficiently of this carbon in competitive mode and to mimic the real-world use, one additional heavy-metal, including Cr(III), and four other commonly occurring metals—Na(I), K(I), Ca(II) and Fe (III)—are added with lead prior to adsorption experiments. It was observed that Pb(II) adsorption capacity of this carbon was not influenced by the presence of other metals. A highly elevated concentration of Na(I), K(I), Ca(II) and Fe(III) in the eluting solution compared to the initial dose suggested possible leaching of those metals from other salts as impurities, water source or even from the carbon itself, although the XPS analysis of the carbon confirmed negligible adsorption of those metals in carbon. From the equilibrium and kinetic data of adsorption, few parameters have been calculated, including distribution coefficient, diffusive time constant and pseudosecond order rate constant. The overall results suggest that these iron and sulfur dual-doped mesoporous carbons can serve as potential adsorbents for removal of lead from drinking water in the presence of other competing metals.
Highlights
Lead poisoning is one of the most common heavy metal poisonings and is quite prevalent in many areas of the world
The most common source of lead poisoning is through drinking water, which is caused by the leaching of lead from the older water pipes that contain lead among their constitutes
As these concentration values are somewhat higher than the initial concentration that we deliberately inserted in the system before adsorption (100 ppb), we investigated the other sources where those metals originated from
Summary
Lead poisoning is one of the most common heavy metal poisonings and is quite prevalent in many areas of the world. Adsorptive separation of lead by porous carbons has been regarded as the most popular choice for purifying drinking water, especially when the initial concentration of lead in water is in the lower range. It was revealed that inserting sulfur functionalities on porous carbon increases its affinity towards heavy-metals [16,17], including lead [18,19] to a great extent. In order to study the competitive adsorption, Cr(III) was used as competing heavy metal along few common metals that are often present in the water, including Na(I), K (I), Ca(II) and Fe(III). In order to mimic the real-world situation for lead contaminated drinking water, the initial concentration of Pb(II) along with other metals is set as 100 parts per billion (ppb or μg/L)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
