Evaluation of Aerogel Spheres Derived from Salix psammophila in Removal of Heavy Metal Ions in Aqueous Solution

Multimedia distribution, partitioning, sources, comprehensive toxicity risk and co-occurrence network characteristics of trace elements in a typical Chinese shallow lake with high antibiotic risk

Although the combined pollution of trace elements and antibiotics has received extensive attention, the fate and toxicity risk of trace elements with high antibiotic risk are still unclear. The multimedia distributions, partitioning, sources, toxicity risks and co-occurrence network characteristics of trace elements in surface water (SW), overlying water (OW), pore water (PW) and sediment (Sedi) samples of 61 sites from Baiyangdian (BYD) Lake were investigated. The trace elements in the SW and OW are derived mainly from traffic and agricultural sources, and those in PW and Sedi samples are primarily from lithogenic and industrial sources. The total toxicity risk index (TRI) of nine trace elements (ΣTRI) in Sedi samples showed a very high toxicity risk (18.35 ± 8.84), and a high combined pollution toxicity risk (ΣΣTRI) was observed in PW (149.17 ± 97.52) and Sedi samples (46.37 ± 24.00). The co-occurrence network from SW to PW became more vulnerable. Generally, total antibiotics and TP may be keystones of trace elements in water and sediment. The high antibiotic risk significantly influenced ΣΣTRI in water samples but not in Sedi samples. The findings provide new implications for the monitoring and control of combined antibiotic-trace element pollution in shallow lakes.

Study on the Structure Characterization and Swelling Properties of the Fe3O4/CMS Composite Membrane

In order to improve the functionality of cellulosic materials research and development of high performance soluble materials. Therefore, the Fe3O4/CMS composite membrane was prepared by using carboxymethyl salix powder (CMS) and Fe3O4 as raw materials, 1-propenyl-3-methylimidazolium chloride and dimethyl sulfoxide as dissolution system. The effects of swelling time, swelling temperature, pH and ionic strength on the swelling performance of Fe3O4/CMS composite membranes and the swelling kinetics of the composite membranes were studied. The structure of the composite membrane was characterized by SEM, FT-IR, XRD and TG. The results showed that the swelling degree reached 5.54 g·g-1, when the swelling time was 45 min, the swelling temperature was 65 °C, the pH was 5 and the ionic strength was 0.08 mol·L-1. The initial phase of dissolution of the composite membrane fits well with the Fickian diffusion model, and the whole dissolution process belongs to the Schott model, indicating that the main role of the dissolution process is the diffusion of water molecules, while the composite membrane can be preserved for a long time at high temperature, which provides sustainability for the composite membrane. The characterization results showed that the surface of Fe3O4/CMS composite film was rough with small grooves. The O-H effect was enhanced and the Fe-O absorption peak appeared at 600 cm-1, indicating that Fe3O4 had been successfully loaded onto the cellulose membrane. The Fe3O4/CMS composite membrane belonged to cellulose type II structure, meanwhile, the composite membrane had good thermal stability.

Ionic liquid [bmim] [TFSI] templated Na-X zeolite for the adsorption of (Cd2+, Zn2+), and dyes (AR, R6)

1-butyl-3-methylimidazolium bis(triflouromethylsufonyl)imide functionalization to Na-X zeolite (IFZ) is the primary goal of this study in order to evaluate its ability to remove heavy metals (Cd²⁺), (Zn²⁺), dyes Rhodamine 6G (R6), and Alizarin Red S (AR) from aqueous streams. IFZ was thoroughly examined using analytical techniques XRD, BET, FE-SEM, and FTIR, to better understand its physical and chemical properties. The surface area and the volume of pores (IFZ; 19.93 m²/g, 0.0544 cm³/g) were reduced in comparison to the parent zeolite (Na-X; 63.92 m²/g, 0.0884 cm³/g). According to SEM, the crystal structure of the zeolite (Na-X) has not been significantly altered by XRD analysis. The mechanism, kinetics, isotherms, and thermodynamic properties of adsorption were all studied using batch adsorption experiments under various operating conditions. IFZ adsorbs dyes (AR; 76.33 mg/g, R6; 65.85 mg/g) better than metal ions (Cd²⁺; 30.68 mg/g, Zn²⁺; 41.53 mg/g) in acidic conditions. The Langmuir isotherm and pseudo-second order models were found to be the most accurate models for equilibrium data. Adsorption is endothermic and spontaneous, as revealed by the thermodynamics of the process. The IFZ can be used in three (Cd²⁺), two (Zn²⁺), four (AR), and five (R6) cycles of desorption and regeneration. For these reasons, IL-modified zeolite can be used to remove multiple types of pollutants from water in one simple step.