Aluminium sulfate synergistic electrokinetic separation of soluble components from phosphorus slag and simultaneous stabilization of fluoride.

In this study, fluoride (F) was stabilized and soluble components, namely phosphate (P), K, Ca, Cr, Mn, and Pb, were extracted from phosphorus slag (PS) by using aluminum sulfate (AS) synergistic electrokinetic. PHREEQC simulation was used to determine the occurrence form of each ion in the PS. The mechanisms by which various electrokinetic treatment methods affected conductivity and pH distribution were carefully investigated. Electrokinetic treatment increased P concentration of the anode chamber from 22.7 mg/L to 63.39 mg/L, whereas K concentration increased from 15.26 mg/L to 93.44 mg/L. After AS-enhanced electrokinetic treatments, the concentrations of the different components were as follows: P, 131.66 mg/L; K, 198.2 mg/L; and Ca, 331.3 mg/L. The removal rate of soluble P in PS slices increased to 80.88% by 1.5 V/cm of treatment, and it increased to 94.04% after AS enhancement treatment. For water-soluble F, the removal rate from the PS slices in the anode region was 86.03%, decreasing F concentration in the electrode chamber to 9.57 × 10-3 mg/L. Different extraction efficiencies and stability levels of each component in the PS were regulated at various electrode regions by using different processes such as electromigration, electro-osmotic flow, flocculation, and precipitation. Good results can be obtained if fluoride is solidified concurrently with the removal or recovery of P, K, Ca, and other elements using 2%-4% AS enhanced electrokinetic treatment. Furthermore, CaSO4·2H2O whiskers were produced in the electrode regions when AS content was 6%. The findings of this study indicated that the AS synergistic electrokinetic method is suitable for stabilizing F and removing heavy metals from PS, thus providing a promising technology for recycling valuable components such as P, K, Ca, and Sr and for the simultaneous production of CaSO4·2H2O whiskers. This study provides insights for developing novel technologies for the clean treatment and high-value utilization of PS.

Study of Semi-Dry High Target Solidification/Stabilization of Harmful Impurities in Phosphogypsum by Modification.

Phosphogypsum (PG) treatment is one of the research hotspots in the field of environmental protection. Many researchers both at home and abroad have devoted themselves to studies on harmless resource treatment of PG, but the treatment technology is unable to meet the demand of PG consumption due to the huge production and storage demands. In order to solve the problem of PG pollution, this study explored the different solidified effects of various modification formulations on the hazardous components in PG, using industrial solid waste calcium carbide slag (CCS) as an alkaline regulator; Portland cement (PC), polyaluminum chloride (PAC) and CaCl2 as the main raw materials of the solidification and stabilization formula and the water content in PG as the reaction medium. The results showed that CCS (0.5%), PC (0.4%) and PAC (0.3%) had a more significant solidified effect on phosphorus (P) and fluoride (F). PAC was added in two steps and reacted under normal temperature and pressure, and its leaching toxicity meets the requirements of relevant standards, which laid an excellent foundation for PG-based ecological restoration materials and filling materials, with low economic cost, simple process and strong feasibility. This will provide great convenience for the later mining and metallurgy.

Study on the Mechanism of Rapid Oil-Water Separation by a Fe3 O4 @PMMA@PDMS Intelligent Superhydrophobic Micro/Nanorobot.

We prepared an environmentally friendly intelligent Fe3 O4 @PMMA@PDMS superhydrophobic oil-absorbing material with simple process and excellent performance, and investigated the effects of different particle sizes of Fe3 O4 , different concentrations of PDMS, and different heating times on the superhydrophobicity of the coating. The best performance of the coating was achieved at a particle size combination of 20/500 nm for Fe3 O4 , a PDMS to Fe3 O4 @PMMA mass ratio of 6 : 1, and a heating time of 2 min at 400 °C. H2-SPSS coating not only has excellent superhydrophobicity, abrasion resistance, self-cleaning property, and chemical corrosion, but also has good flux and efficiency for separating oil-water mixture, with fluxes of 40,540, 32,432, and 37,027 Lm-2 h-1 for trichloromethane, dichloromethane and bromoethane, respectively, and separation efficiencies of 99.78 %, 99.74 % and 99.73 %, respectively. In addition, we also prepared a superhydrophobic magnetic polyurethane (SPPU) sponge using Fe3 O4 @PMMA@PDMS, which not only has a good oil absorption capacity of 18-44 g/g for different oil substances, it can also move directionally by magnet attraction and absorb oil along a fixed path. Under the control of the magnet, SPPU completes the whole oil absorption process in only 4 s, showing excellent oil absorption and intelligence.

Chitosan-modified magnetic carbon nanomaterials with high efficiency, controlled motility, and reusability-for removal of chromium ions from real wastewater.

Hexavalent chromium Cr(VI) is one of the most hazardous oxygen-containing anions to human health and the environment. Adsorption is considered to be an effective method for the removal of Cr(VI) from aqueous solutions. Based on an environmental perspective, we used renewable biomass cellulose as carbon source and chitosan as functional material to synthesize chitosan-coated magnetic carbon (MC@CS) material. The synthesized chitosan magnetic carbons were uniform in diameter (~ 20 nm) and contain a large number of abundant hydroxyl and amino functional groups on the surface, meanwhile owning excellent magnetic separation properties. The MC@CS exhibited high adsorption capacity (83.40 mg/g) at pH 3 and excellent cycling regeneration ability when applied to Cr(VI) removal in water, removal rate of Cr(VI) (10 mg/L) was still over 70% after 10 cycles. FT-IR and XPS spectra showed that electrostatic interaction and reduction with Cr(VI) are the main mechanisms of Cr(VI) removal by MC@CS nanomaterial. This work provides an environment-friendly adsorption material that could be reused for the removal of Cr(VI) in multiple cycles.

Advances in the research of carbon-, silicon-, and polymer-based superhydrophobic nanomaterials: Synthesis and potential application.

With the rapid development of science and technology, superhydrophobic nanomaterials have become one of the hot topics from various subjects. Due to their distinct properties, such as superhydrophobicity, anti-icing and corrosion resistance, superhydrophobic nanomaterials are widely used in industry, agriculture, defense, medicine and other fields. Hence, the development of superhydrophobic materials with superior performance, economical, practical features, and environment-friendly properties are extremely important for industrial development and environmental protection. Aimed to provide a scientific and theoretical basis for the subsequent study on the preparation of composite superhydrophobic nanomaterials, this paper reviewed the latest progress in the research of superhydrophobic surface wettability and the theory of superhydrophobicity, summarized and analyzed the latest development of carbon-based, silicon-based and polymer-based superhydrophobic nanomaterials in terms of their synthesis, modification, properties and structure sizes (diameters), discussed the problems and unique application prospects of carbon-based, silicon-based and polymer-based superhydrophobic nanomaterials.

Nano Biomass Material functionalized by ß-CD@Ce(NO)3 as a high performance adsorbent to removal of fluorine from wastewater.

Fluorine pollution has become one of the key issues of water pollution, and the adsorption materials for efficient removal of fluorine ions have attracted much attention. It is rarely reported that the self-synthesized biomass materials were functionalized by the ß-CD@Ce(NO)3. This paper mainly proposed a new synthetic method of the self-synthesized biomass materials were modified by the ß-CD@Ce(NO)3 and removal of fluorine ions. The effects of this materials on the adsorption efficiency of fluorine ions under different conditions were explored, and the kinetic and thermodynamic simulations were carried out. The results show that the self-synthesized biomass materials were modified by the ß-CD@Ce(NO)3 has significant pore structure, large specific surface area and multi-functional group. Adsorption experiment showed that the reaction reached adsorption equilibrium at 30 min. The removal rate of fluorine ions reached 93.13%, and the fluorine ions adsorption capacity was 37.25 mg/g under neutral conditions. The material can be recycled for more than 5 times, and the adsorption efficiency remains above 94%. The adsorption kinetics accorded with the pseudo second-order model and the adsorption isotherm equation is in line with the Langmuir isotherm adsorption model. PO43- and CO32- have the most impact on fluorine ions adsorption. This method reduces the synthesis cost of high-performance adsorption materials and improves the adsorption performance, which is conducive to the popularization and application in the future.

Study on the mechanism of rapid degradation of Rhodamine B with Fe/Cu@antimony tailing nano catalytic particle electrode in a three dimensional electrochemical reactor.

A novel particle electrode based on antimony tailings microspheres was successfully constructed by ultrasonic immersion calcination method, and the degradation of RhB was studied in a three-dimensional electrochemical reactor (3DER). It was characterized by XRD, SEM, EDS, XPS, cyclic voltammetry and linear sweep voltammetry. When the pH value is 5.00, the dosage of Fe/Cu@antimony tailing is 1.50 g/L, the initial concentration is 100 mg/L, and the current density is 20 mA/cm2, the degradation efficiency is the best (99.40% for RhB and 98.81% for TOC) within 15 min. The results show that in the three-dimensional electrochemical oxidation system, electrochemical oxidation and electro Fenton oxidation occur at the same time to cause the increase of hydroxyl radicals. According to LC-MS analysis and EPR characterization, it can be found that the main degradation mechanism of RhB is that hydroxyl radicals continuously attack RhB, and realize rapid degradation of RhB through deethylation, deamination, dealkylation, decarboxylation, chromophore splitting, ring opening and mineralization. Fe/Cu@antimony tailing particles are both electrodes for electrochemical oxidation and catalysts for Fenton oxidation. The degradation effect of RhB remained at 94% after 6 cycles, and the leaching rates of Fe and Cu are only 1.20% and 0.79%, indicating that Fe/Cu@AT had significant stability. This work provides a new insight into the establishment of an efficient and stable three-dimensional electrocatalytic particle electrode.

Advances in the Research of Photo, Electrical, and Magnetic Responsive Smart Superhydrophobic Materials: Synthesis and Potential Applications.

With the rapid advancement of technology, the wettability of conventional superhydrophobic materials no longer suffice to meet the demands of practical applications. Intelligent responsive superhydrophobic materials have emerged as a highly sought-after material in various fields. The exceptional superhydrophobicity, reversible wetting, and intelligently controllable characteristics of these materials have led to extensive applications across industries, including industry, agriculture, defense, and medicine. Therefore, the development of intelligent superhydrophobic materials with superior performance, economic practicality, enhanced sensitivity, and controllability assumes utmost importance in advancing technology worldwide. This article provides a summary of the wettability principles of superhydrophobic surfaces and the mechanisms behind intelligent responsive superhydrophobicity. Furthermore, it reviews and analyzes the recent research progress on light, electric, and magnetic responsive superhydrophobic materials, encompassing aspects such as material synthesis, modification, performance, and responses under diverse external stimuli. The article also explores the challenges associated with different types of responsive superhydrophobic materials and the unique application prospects of light, electric, and magnetic responsive superhydrophobic materials. Additionally, it outlines the future directions for the development of intelligent responsive superhydrophobic materials.