ABSTRACT This study evaluated the thermal and electrical dehydration performance of eight polyether amines with varying molecular weights and HLB values for W/O crude oil emulsion breaking before and after alkylation modification. The experimental results demonstrated that the dehydration rates of polyether amine both before and after modification were less than 30%. However, all polyether amines can enhance the electrical dehydration rate, with the modified polyether amines having higher dehydration rate. Specifically, the modified polyether amine P20-H2.8 achieved a dehydration rate of 64.29% under conditions of 4 kV, 60°C, and a dosage of 200 mg/L, which is 2.25 times higher than that without any chemical agent addition. Interfacial property studies revealed that the modified polyether amines exhibited superior interfacial activity and stronger ability to reduce the elastic modulus of the oil-water interface under the electric field, thereby contributing to their better demulsification performance. Nevertheless, the electrical dehydration rate of the modified polyether amine P20-H2.8 was still much lower than that of conventional block polyether demulsifier, indicating a need for further improvement in interfacial activity. Although the research results of polyether amines are not very good, it expands the research direction of demulsifiers and provides some new insights for demulsifier development.

ABSTRACT Produced water from polymer flooding (PFPW) presents significant treatment challenges due to the presence of emulsified oil droplets and high concentration of hydrolyzed polyacrylamide (HPAM). This study evaluates a hybrid ozonation – coagulation (HOC) process for PFPW treatment, focusing on the effects of key water quality parameters, including HPAM concentration and molecular weight, total dissolved solids (TDS), and Ca2+ concentration. Treatment performance was assessed in terms of floc size, residual oil content, and turbidity removal. Supporting analyses of solution viscosity, zeta potential, and oil – water interfacial tension provided mechanistic insights into salinity-dependent behavior. Optimal performance was achieved at 200 mg/L HPAM with a molecular weight of 12 MDa. Moderate TDS (2–10 g/L NaCl) and Ca2+ concentrations (600 mg/L) enhanced demulsification via electrical double-layer compression and charge neutralization. In contrast, excessive polymer or ionic concentrations led to emulsion restabilization and reduced efficiency. These findings offer guidance for identifying suitable water quality conditions for the HOC process and contribute to enhancing the reliability of its engineering design in the treatment of PFPW.

ABSTRACT Given the low concentration of heavy metal pollution in water bodies, a microporous structure was proposed to enhance the flocculation net capture effect, improve flocculation efficiency, and reduce chemical usage. This approach utilizes permanent magnets and stainless steel balls to establish microporous structures, harnessing the hydraulic retention phenomenon and the net capture flocculation mechanism. Test results indicated that the concentration of Cd(II) in the simulated wastewater ranged from 2.09 to 4.96 × 10−3 kg/m3. The dosage of poly aluminum chloride (PAC) was 70 × 10−3 kg/m3, and nonionic polyacrylamide (NPAM) was 0.5 × 10−3 kg/m3, resulting in a removal efficiency of 97.99% to 99.41%. The fractal dimension of the flocs was high, with elevated chromium content, which efficiently contributed to net capture. The front end of the microporous structure exhibited a large vorticity volume and small shear force, enhancing the net capture capacity of the flocs. Additionally, the microporous structure facilitated floc interception, demonstrating the potential for practical application in similar reaction systems.

ABSTRACT Twenty-four coefficients of Richardson-Horner Distribution-Ratio (DR) model, accounting for interactions among major PUREX solutes such as U(VI), Pu(IV), U(IV), Pu(III), and HNO₃, as well as minor solutes including various actinide nitrates and fission products, have been optimized, leading to the development of the “Richardson-Horner-Singh DR model.” This study categorizes the data into high molal Pu flowsheet conditions (Set-1: Pu > 0.08 m and U > 0.2 m) and low molal Pu flowsheet conditions (Set-2: Pu ≤ 0.08 m and U ≤ 0.2 m), resulting in a significant enhancement in the predictive accuracy of solute Distribution-Ratios. A set of ordinary differential equations based on material balance principles has been developed and implemented in the SIMPUREX (SIMulation of PUREX) code to model transient and steady-state solute concentration profiles across differential mass transfer contactors in reprocessing facilities. Additionally, Aggregate-HETS (∑HETSi) is computed using the indigenous SIMPULCO (SIMulation of PULsed COlumn) code, which employs partial differential equations (PDEs) incorporating diffusion, convection, mass transfer, and chemical kinetics. SIMPULCO facilitates performance assessment of extraction units, exploring alternative designs, column configurations, criticality conditions, validation of design parameters, and scaling up of pulsed columns. Comparative analysis demonstrates the superior accuracy of the Richardson-Horner-Singh DR model, SIMPUREX, and SIMPULCO over existing models, underscoring their significance in refining nuclear fuel reprocessing technologies.

ABSTRACT Tungsten mining, smelting, and recycling generate contaminated wastewater, posing a significant global environmental threat due to tungsten’s potential toxicity. As a vital strategic resource with wide applications, effective water treatment is crucial. However, research on tungsten adsorption techniques remains limited, lacking comprehensive reviews. This survey compiles common tungsten adsorption methods and adsorbents. Removal efficiency critically depends on adsorbent physicochemical properties and background water chemistry. The review analyzes key influencing factors and adsorption mechanisms. It also identifies future research priorities to enhance tungsten removal. The primary goal is to provide a thorough database on effective tungsten extraction techniques. A significant need persists for developing novel, high-efficiency adsorbents that are low-cost, highly stable, and easily produced/manufactured for practical use. Effective tungsten wastewater treatment necessitates a balanced assessment of conventional and emerging materials (especially functionalized porous and ion-imprinted adsorbents). Selection decisions must prioritize site-specific water chemistry, practical scalability, and eco-economic efficiency, moving beyond just laboratory performance.

ABSTRACT Volatile organic compounds (VOCs) pose serious environmental and health risks, and among various removal techniques, adsorption – particularly using zeolites – has emerged as a highly effective solution. However, conventional powdered zeolites often face limitations in large-scale applications due to handling, regeneration, and mechanical instability. To address these challenges, this study aims to transform ZSM-5 zeolite powder into mechanically robust, regenerable zeolite beads through a multi-step synthesis process, while maintaining high VOC adsorption capacity and enabling efficient regeneration in humid conditions. Initially, powder zeolite was converted to sphere beads via phase inversion, then coated with MnO2 through incipient wetness impregnation. Following several modifications, experimental data were obtained with the support of XRD, BET, SEM-EDX, FTIR and TGA, verifying the crystalline and well-prepared zeolite/chitosan beads. The investigation on bead size, density, void fraction and mechanical strength was also conducted. The 5%MnO2/Z9C2 beads had a significantly high regeneration efficiency of 93.4% at the first cycle and sequentially maintained an average regeneration yield of 86.55% following 4 cycles, with the highest IPA adsorption capacity of 0.344 mmol per gram of catalyst.

ABSTRACT Quercetin, belonging to a class of compounds called flavanols is an eminent flavonoid that has gained appreciable attention in the biomedical field owing to its wide array of pharmaceutical properties. Regardless of its numerous applications in the field of medicine, it has certain drawbacks which restrict its use. It has low water solubility, poor permeability, and poor bioavailability that have contributed to its limited application. In order to address the above stated problem, we have done a study that focuses on these issues by creating polymeric nanoparticle of quercetin via nanoprecipitation. Ethanolic quercetin solution was added to the PVP solution of different concentrations under continuous stirring, and the resulting solution was then vacuum dried to obtain nanoparticles in powder form. These PVP entrapped Quercetin nanoparticle so obtained had a size of 100.30 ± 5.3 nm, as calculated through DLS and zeta potential of −19.3 ± 0.14 mV. These particles, Qu-PVP-NPs achieved drug loading capacity of 61.69 ± 0.47% and were readily dispersible in water, thereby boosting absorption significantly. Qu-PVP-NPs were analyzed further by UV-spectrophotometry, SEM and XRD.

ABSTRACT This study aims to optimize essential oil (EO) yields through Ultrasonication-Assisted Extraction-Hydrodistillation (UAE-HD), focusing on Cymbopogon winterianus Jowitt ex Bor and Salvia rosmarinus ;(L.) Spenn. The UAE stage was optimized using Response Surface Methodology (RSM) with Box-Behnken Design (BBD). The independent variables i.e. volume of solvent, sonication temperature, and sonication duration were optimized against its yield in 15 designs. The optimum condition via the quadratic model was validated through ANOVA and the optimum results were achieved at 50°C with sonication for 20 minutes in 250 mL of distilled water. The EO component of both materials, either by UAE-HD or HD conventional, was analyzed using Gas Chromatography-Mass Spectroscopy (GC-MS). The main components of C. winterianus EO were citronella (36.27 %), geranial (29.75 %), and β-citronellol (18.41 %), while S. rosmarinus EO contained 1.8-cineole (23.06 %), α-pinene (17.50 %), neral (13.03 %), and verbenone (8.86 %). Leaf morphology differences were analyzed using Scanning Electron Microscopy (SEM), revealing that ultrasonication caused damage to the secretory glands, thereby accelerating the release of volatile components. This finding demonstrates the practicality of the proposed method for achieving higher EO yields.

ABSTRACT As an industrial solid waste with large output and storage capacity, the green and efficient recycling technology of iron tailings has always been the current research difficulty. Suspended magnetization roasting can further improve the utilization rate of iron tailings by changing the occurrence state of iron in iron tailings, so it has become a research hotspot in the reuse technology of iron tailings resources. However, there are few implementation examples of this method and there are still some problems in industrial application. Based on the existing research, this paper uses the method of suspension magnetization roasting-magnetic separation to recover the valuable mineral limonite (Fe2O3 · nH2O) in a tailings pond sample in Dali, Yunnan Province through a combination of mechanism analysis and experimental verification. Mechanism analysis indicates that by controlling the reaction conditions, Fe2O3 can be almost completely converted to Fe3O4, thereby increasing the magnetic difference between valuable minerals and gangue minerals. Experimental results show that under the optimal conditions of CO concentration at 25%, total gas volume at 500 mL/min, a reducing agent ratio of CO: H2 = 1:3, roasting temperature at 803 K, roasting time at 25 min, magnetic field intensity I at 1700Gs, and magnetic field intensity II at 2100Gs, the tailings sample with an iron grade of 23.76% can be transformed into iron concentrate with an iron grade of 57.75%. The separation indices achieved are a recovery rate of 69.54% and a yield of 34.52%. Experimental results such as chemical composition analysis, XRD detection, and iron phase analysis confirm that Fe2O3 in the original tailings sample is almost completely converted to Fe3O4, consistent with the mechanism analysis results. The efficient utilization of this iron tailings resource has been successfully realized, consistent with the results of mechanism analysis, the efficient utilization of iron tailings resources has been successfully realized, which provides a certain reference for the efficient utilization of new technologies of iron tailings, and also has certain reference significance for the industrial application of suspension magnetization roasting.

ABSTRACT Despite the remarkable progress in wastewater treatment strategies over the past decades, the degradation of micro-pollutants still remains a challenging domain to explore, and often, the treated effluent is disposed of without taking care of the same. In this study, a conical plug-and-play reactor (CPPR) was designed to be retrofitted into the existing tertiary treatment point for treating real-life pharmaceutical effluents. Two pharmaceutical effluents (sample I/II) from different treatment plants were treated in CPPR by optimizing the operational parameters and conjugating with other oxidizing agents. The standalone CPPR resulted in the highest COD reduction of 34% and 37% for samples I and II at the optimized values of 2400 rpm, 150 passes, and pH 2.0. The CPPR conjugated with advanced oxidation processes showed an optimal COD reduction of 84%, 81%, and 90% for sample I and 87%, 84%, and 92% for sample II at 0.3 g/L of H2O2, 1:3 Fe2+:H2O2 ratio, and 3 g/h of O3 loading, respectively. From an energetic and economic point of view, the performance of HC+O3 surpassed that of other oxidizing agents. Further, the techno-economic feasibility was demonstrated with a break-even analysis for financial estimations of potential pilot-scale incorporation of this technology.