Separation Science and Technology
ISSN / EISSN: 01496395 / 15205754
Published by: Informa UK Limited
Total articles ≅ 8,994
Latest articles in this journal
Separation Science and Technology pp 1-22; https://doi.org/10.1080/01496395.2022.2147440
Interaction of 3-Amino-1 H–1,2,4-triazole with 4,4“-Dihydroxybenzil yielded 4,4”-((1E)-1,2-bis((1 H–1,2,4-triazol-3-yl)imino)ethane-1,2-diyl)diphenol. The adsorbent (TIHP) was made by subjecting the synthesized Schiff base to a phosphorylation reaction; its structure was validated by FTIR, TGA, 1HNMR, 13CNMR, GC-MS, and Phosphorus-31 nuclear magnetic resonance (31P-NMR). Chromium oxyanions (Cr(VI)) in water were successfully removed by using the newly synthesized adsorbent (TIHP). Many different variables, namely; the initial concentration of Cr(VI), the period of interaction, the temperature, the amount of the adsorbent dosage, and the pH of aqueous were tested via the batch technique. Maximum sorption efficiency were obtained at pH 2, 45 min contact time, 0.08 dose, at room temperature. When exposed to the proposed foreign ions, Cr(VI) desorption)‘s behavior modifies. The novel adsorbent had an extreme adsorption capability of 307.07 mg/g for Cr(VI) at ambient temperature. Adsorption isotherms could be explained by Freundlich’s isotherm model. The pseudo-second-order equation provided tight limits on the kinetic outcomes. Thermodynamic analyses confirm that the up taking process was spontaneous and endothermic.
Separation Science and Technology pp 1-15; https://doi.org/10.1080/01496395.2022.2151470
Phytochemical compounds generally protect and prevent their plants from adverse effects. These chemicals are promising candidates in the pharmaceutical, food, and cosmetic industries. Many studies have highlighted the phytochemical constituents of Aegle marmelos and their functionalities. Several bioactive compounds of A. marmelos have been reported for their potential to either prevent or reduce the risk of diseases like cancer, diabetes, cardiovascular disorder, and bacterial infections. Multiple extraction methods with different parameters and results are reported for extracting phytoconstituents from A. marmelos. The commonly reported extraction techniques are divided into conventional and non-conventional methods. Though conventional techniques such as maceration and cold percolation are simple to implement, they require a long duration and a large amount of solvent. Microwave- and ultrasonic-assisted techniques are faster and more efficient than conventional methods. Choice of solvent, duration of extraction, and temperature are common process parameters that are to be optimized for each technique. The choice of extraction method and optimization of process parameters are critical for the process scaleup for extracting valuable phytochemicals from A. marmelos. Thus, this review consolidates the importance of the plant by analysis of the bioactive compounds present in it and reviews the extraction techniques suitable for the tree.
Separation Science and Technology pp 1-13; https://doi.org/10.1080/01496395.2022.2151472
An electro-swirling coupling device coupled with electric field and centrifugation can achieve demulsification and dewatering of emulsion efficiently and economically. But, the vortex structure and its implication on separation performance under the coupling condition are unclear. Accordingly, a vortex analysis for the coupling separator was conducted numerically, and the effect of eccentricity on the efficiency was investigated. The results show that the iso-vortex surface is twisted and fluctuates. And there is a vibrational radial deviation between the vortex core and central axis, and increasing inlet velocity and voltage amplitude can increase the radial deviation of the vortex at the z-coordinate range from 250 to 550 mm. Furthermore, the underlying reason for the increase in vortex eccentricity is different where the electric coalescence is for the increase in voltage amplitude and the fluid kinetic energy is for the increase in inlet velocity. Moreover, the separation efficiency increases with the increase in vortex eccentricity at the case that the coalescence is dominant, but the separation efficiency gradually decreases with the increase in breakage rate and the droplet breakup is dominant.
Separation Science and Technology pp 1-13; https://doi.org/10.1080/01496395.2022.2151471
In this study, a superconducting high gradient magnetic separation (S-HGMS) technology was used to separate and extract quartz from sea sand. Under optimal conditions (i.e., a magnetic flow ratio of 0.085 T·s/m, slurry flow velocity of 400 ml/min, and pulp concentration of 40 g/L), the SiO2 grade increased from 79.45% of the raw material to 91.35% of quartz concentrate, and the removal rate of Al and Fe reached 91.97% and 82.10%, respectively. Weakly magnetic particles in sea sand were selectively transformed to tailings, and the pre-concentration of quartz was achieved under a high magnetic field intensity. The high magnetic field intensity and mineral magnetic differences were the critical factors influencing the magnetic separation of quartz from sea sand. The S-HGMS technology achieved effective pre-concentration of quartz from sea sand, reducing the handling capacity and providing a high-quality material for subsequent quartz refinement processes.
Separation Science and Technology pp 1-35; https://doi.org/10.1080/01496395.2022.2145222
In recent years, significant advances have been made in the field of functionalized membranes. With the functionalization using various materials, such as polymers and enzymes, membranes can exhibit property changes in response to an environmental stimulation, such as heat, light, ionic strength, or pH. The resulting responsive nature allows for an increased breadth of membrane uses, due to the developed functionalization properties, such as smart-gating filtration for size-selective water contaminant removal, self-cleaning antifouling surfaces, increased scalability options, and highly sensitive molecular detection. In this review, new advances in both fabrication and applications of functionalized membranes are reported and summarized, including temperature-responsive, pH-responsive, light-responsive, enzyme-functionalized, and two-dimensional material-functionalized membranes. Specific emphasis was given to the most recent technological improvements, current limitations, advances in characterization techniques, and future directions for the field of functionalized membranes.
Separation Science and Technology pp 1-17; https://doi.org/10.1080/01496395.2022.2145221
PAN/TiO2/CNT and PAN/TiO2/CNT-PVA composite nanofibrous membranes with photocatalytic activity were successfully synthesized using electrospinning. The effect of CNT concentration and PVA coating on the membrane surface toward the membrane performances was investigated. TiO2 anatase phase was exist on the respective membranes. SEM morphological investigation revealed the random orientation of the nanofibers with beads decorated in each strand. The PAN/TiO2/CNT composite nanofiber membrane exhibited high performance for the removal of cationic organic dye methylene blue (MB) in a cross-flow photocatalytic membrane reactor under low power visible light of LED lamp (14.5 W) and a constant pollutant flow rate of 0.21 L/min. The presence of TiO2/CNT photocatalyst was proven to prolong the lifetime of the photocatalytic membrane and retard membrane fouling to the maximum extent. PAN/TiO2/CNT membrane has displayed 100% MB rejection for the first 8 h of operation. Both, PAN/TiO2/CNT and PAN/TiO2/CNT-PVA maintained their membrane performances and did not show major flux decline even after five recycling uses. The incorporation of TiO2/CNTs on PAN nanofibers has resulted in a durable photocatalytic membrane for the effective removal of dye waste using a cross-flow membrane reactor.
Separation Science and Technology pp 1-14; https://doi.org/10.1080/01496395.2022.2145223
The inline gas-liquid cyclone separator has been gradually used in oil & gas industry due to its high separation efficiency and less footprint. However, under the inlet flow conditions with large range of gas volume fractions, the research on structure design and separation performance are seriously insufficient. The preliminary structural design of the inline gas-liquid separator was carried out according to the particle separation theory, and the key structural parameters were optimized by using the Response Surface Method (RSM) together with Computational Fluid Dynamics (CFD). The structure optimization has improved the degassing efficiency by 17.44% and dehydration efficiency by 7.59%. With air and water as working medium, the separation performance of the inline gas-liquid cyclone separator was experimentally investigated in laboratory under a large range of gas volume fractions. The results show that the separation efficiency for both degassing and dehydration can exceed 80% with the inlet gas volume fraction ranges from 0.2 to 0.8. The optimum normalized flow split and liquid volume flow rate are 0.9 –1.2 and 8 m3/h, respectively.
Separation Science and Technology pp 1-11; https://doi.org/10.1080/01496395.2022.2145224
The objective of this work was to study sorption of dissolved organic matter (DOM) onto Bondesil PPL and Bond Elut PPL sorbents with particular attention to impact of sorption loading on molecular composition of the DOM isolated with a use of solid phase extraction (SPE). It was shown that the batch sorption isotherms were best fitted with the Langmuir model, the sorption constants were 8.6·103 L·kgOC−1 and 10.7·103 L·kgOC−1 for Bond Elut PPL and Bondesil PPL, respectively. Breakthrough curves were satisfactorily fitted by a logistic equation; the maximum sorbent loading was 13% (wt. dissolved organic carbon) for both sorbents. The relationship between loading values and optical descriptors of the DOM at the column exit showed preferential sorption of low molecular weight aromatic DOM components in the range of low loading values (up to 4%), the similar trends were observed for size exclusion chromatography (SEC) measurements. Much lesser impact of loading onto molecular composition was observed within the range from 4 to 8% dissolved organic carbon (DOC). Given high recovery values (70–85%) in this loading range, it can be recommended as preferential for conducting DOM isolation from natural waters using SPE PPL-modified sorbents.
Separation Science and Technology pp 1-13; https://doi.org/10.1080/01496395.2022.2141650
Electrokinetic remediation (EKR) is a promising technique for the treatment of contaminated soils and sediments. However, the application of EKR to metal(oid)-contaminated mine wastes with varying mineralogy and physicochemical properties has not been fully characterized. This paper evaluates the potential of EDTA-enhanced EKR as a means to remove trace metal(oid)s (Cu, Cd and As) and major metals (Fe, Al and Mg) from a phosphate mine tailings material. Controlled laboratory EKR experiments were performed, in which the electrolyte EDTA concentration was varied between 0.1 and 1 M and the voltage gradient between 24 and 32 V. Migration of the studied contaminants increased proportionally to increasing EDTA concentration and applied voltage gradient, and the obtained average removal efficiencies of Al, Mg, Cu, Cd and As reached up to 29%, 10%, 26%, 28% and 22%, respectively, within a week. Differences in metal mobilization could be explained by their mineral hosts and aqueous speciation under the imposed geochemical conditions during EKR, which were corroborated by aqueous geochemical equilibrium modeling using PHREEQC. Our results suggest that EKR could be a feasible remediation option for select metal(oid)-enriched mine waste fractions following further optimization.
Separation Science and Technology pp 1-16; https://doi.org/10.1080/01496395.2022.2140437
Anaerobic process is a promising technique for textile effluent treatment. However, poor solid–liquid separation and residual chemical oxygen demand (COD) in the treated effluent limit its scope for industrial applications. The study analyzed the nature of suspended microbial biomass in the anaerobically treated effluent and further targeted its feasible separation process. The size of the majority of suspended biomass (82%) particles ranged from 500 to 1000 nm. The suspended biomass showed 37.13% hydrophobicity and −15.4 mV zeta potential. The optimization of the coagulation-flocculation (CF) process showed 93% turbidity removal at 400 mg/L of alum, 8 mg/L of a cationic polymer and acidic pH 4, through one variable at a time approach. The optimized results using Central Composite Design (CCD) were experimentally validated, and 97% turbidity removal was recorded at 400 mg/L alum concentration, 12 mg/L of the cationic polymer, and pH 3.2. The results obtained were statistically significant, with a high regression coefficient (R2 = 0.97) at 95% confidence limits. The final treated effluent after CF showed 67% COD removal (from 862 ± 40 to 280 ± 14 mg/L) with 83% color removal (from 740 to 124 Hazen). Hence, the integration of the CF process with the anaerobic process could be a promising approach for textile effluent treatment. GRAPHICAL ABSTRACT