Removal of Hg²⁺ and methylmercury in waters by functionalized multi-walled carbon nanotubes: adsorption behavior and the impacts of some environmentally relevant factors

Abstract

Adsorption of Hg2+ and methylmercury (MeHg) to multi-walled carbon nanotubes (MWCNTs) modified, respectively, with hydroxyl, amine and carboxyl groups was studied. The effect of various factors like the initial pH, natural organic matter (NOM), Cl -and adsorbent dose on the sorption efficiency were evaluated. It was found that amine-modified MWCNTs showed a strong adsorption capacity to Hg 2+ and MeHg, and the removal efficiency could reach up to 92% (0.5 g/L MWCNTs, and 100 μg/L Hg 2+ and MeHg) which is independent of pH.

Fast, Cost-effective and Energy Efficient Mercury Removal-Recycling Technology

“…Note that Zhang et al . 22 . reported Fe 3 O 4 @SiO 2 –SH sorbent for mercury removal and with the increase of pH, removal efficiency slowly increased.…”

Sulfhydryl functionalized carbon quantum dots as a turn-off fluorescent probe for sensitive detection of Hg2+

“…However, expensive and complex instruments, a lengthy process and procedures for pre-treatment of complex samples all limit the application of these methods. There have been many novel sensors developed in recent years for measuring Hg 2+ based on functionalized multi-walled carbon nanotubes, 10 metal nanoparticles 11,12 and semiconductor quantum dots (QDs). 13 Semiconductor QDs have also been widely investigated and used as fluorescent probes due to their unique optical properties and surface modification.…”

Adsorption of Hg(II) ions from aqueous solution by thiosemicarbazide-modified cellulose adsorbent

“…Previous studies have examined functionalized adsorbent preparation techniques, which offer flexibility in design and operation and in many cases facilitate the reacquisition of the precious metal ions, yielding additional economic value (Hoai et al 2010). Activated carbon (AC) adsorbents (Hadi et al 2015;Largitte and Pasquier 2016;Park and Lee 2018), carbon nanotubes (CNTs) (Wang et al 2015;Oyetade et al 2017;Zhang et al 2017), and functionalized chitosan (Kheirandish et al 2017;Dinu et al 2018;Mousavi et al 2018) are widely used in the removal of heavy metal contaminants. Bioadsorbents, such as fungi (Yusuf and Tekin 2017;Pourkarim et al 2017), dead biomass (Cheng et al 2017), and bacteria (Qian and Zhan 2016;Manasi et al 2018), are also widely used.…”