Synthesis of ultrathin hybrid membranes via the co-polymerization of acrylic acid, styrene and molybdenum disulfide and their high adsorption selectivity for lead(II) in the mixture of metal ions

Tianrui Yang; Yu Liu; Jingyi Chen; Junsheng Liu; Shan Jiang; Xiaoxue Zhang; Chunyu Ji

doi:10.1016/j.envpol.2024.124019

Synthesis of ultrathin hybrid membranes via the co-polymerization of acrylic acid, styrene and molybdenum disulfide and their high adsorption selectivity for lead(II) in the mixture of metal ions

Environ Pollut. 2024 Apr 23:350:124019. doi: 10.1016/j.envpol.2024.124019. Online ahead of print.

Authors

Tianrui Yang¹, Yu Liu¹, Jingyi Chen¹, Junsheng Liu², Shan Jiang¹, Xiaoxue Zhang¹, Chunyu Ji¹

Affiliations

¹ School of Energy, Materials and Chemical Engineering, Hefei University, 99 Jinxiu Road, Hefei, 230601, China.
² School of Energy, Materials and Chemical Engineering, Hefei University, 99 Jinxiu Road, Hefei, 230601, China. Electronic address: jsliu@hfuu.edu.cn.

PMID: 38663506
DOI: 10.1016/j.envpol.2024.124019

Abstract

Lead(II) is a potential carcinogen of heavy-metal ions (HIs). With the wide application of Pb-bearing products including lead alloy products, and new-energy lead-ion batteries, lead pollution has become a tricky problem. To solve such a difficulty, novel ultrathin MoS₂-vinyl hybrid membranes (MVHMs) with a "spring" effect were synthesized via co-polymerization of acrylic acid, styrene and molybdenum disulfide (MoS₂) and their adsorptions for HIs were explored. The "spring" effect derived from the interaction between the tendency of the short polyacrylic acid (PAA) chain connected with MoS₂ to spread outward and the coulomb force between layers from MoS₂ (s-MoS₂), which enlarge the spacing of MoS₂ layers without changing the number of layers after membrane formation, which changes the swelling membrane to a dense membrane and reduces the original thickness from 0.5 cm to 0.011 mm in the thickness direction. The adsorption experiment revealed that these MVHMs had super adsorption performance and high selectivity for Pb²⁺ by comparison with other five metal ions: Cu²⁺, Cd²⁺, Ni²⁺, Cr³⁺ and Zn²⁺. Especially, the adsorption quantity of MVHMs for Pb²⁺ could approach 2468 mg/g and the maximum adsorption ratio of q_e[Pb²⁺]/q_e[Cu²⁺] can reach 10.909. These values were much larger than the data obtained with the adsorbents reported in the last decade. A variety of models are applied to evaluate the effect of ionic groups. It was confirmed that -COOH plays a key role in adsorption of HIs and s-MoS₂ also has a certain contribution. Conversely, ion exchange plays only a minor role during the period of adsorption process. Effective diffusion coefficient (D_eff) of Pb(II) had the largest values among these metal ions. Hence, these hybrid membranes are promising adsorbents for the removal of Pb²⁺ from water containing various ions.

Keywords: Adsorption; High selectivity; MoS(2); PAA; Spring effect; Ultrathin membrane.