Stripping Efficiency Research Articles

Extraction of molybdenum, cobalt, and nickel from acidic leach solution of molybdenum leach residue of spent hydrodesulfurization catalyst

ABSTRACT After the extraction of molybdenum from the spent HDS catalyst, a residue containing aluminum, nickel, cobalt, and a small amount of molybdenum was obtained. The simultaneous recovery of nickel, cobalt, aluminum, and residual molybdenum from molybdenum leach residue can be achieved through hydrochloric acid leaching. In the work presented herein, the extraction of molybdenum, cobalt, and nickel from the acidic leach solution of molybdenum leach residue was investigated. Trioctyl tertiary amine can selectively extract cobalt and molybdenum from the acidic leach solution, the extraction of both cobalt and molybdenum reached more than 99% after two-stage countercurrent extraction. The combination of pure water and 25% ammonia water can be utilised for the separation and extraction of cobalt and molybdenum from the loaded cobalt-molybdenum organic phase. After the extraction of cobalt and molybdenum, a synergistic extraction system comprising decyl 4-picolinate and dinonylnaphthalene sulfonic acid can be employed for nickel extraction, achieving a nickel extraction exceeding 99.70% while maintaining aluminum extraction at only 0.32% after undergoing four-stage countercurrent extraction. The nickel stripping efficiency can reach 99.50% after four-stage countercurrent stripping, using a stripping agent of 2 mol/L H2SO4.

Vibration reduction index improvement by adding resilient strips: influence of junction properties

Resilient strips can be used to decrease the structural transmission in junctions and thus limit the flanking sound transmission in buildings. In the standard ISO 12354-1, the efficiency of a resilient strip is characterized by the vibration reduction index improvement. To evaluate the vibration reduction improvement, a standardized measurement method is needed. However, the vibration reduction improvement is not an intrinsic material parameter of the resilient strip and can depend on the mounting conditions and junction geometry. In this paper, the vibration reduction index improvement is evaluated by means of numerical simulations carried out with a statistical model for junctions with resilient strips. The model was first validated by laboratory measurements. While the influence of the junction type (L, T or X) and transmission path (straight on or around the corner) is limited, the influence of the plate properties (mass and bending stiffness) cannot be neglected, with differences in vibration reduction improvement of up to 20 dB.

High‐frequency (470 kHz) ultrasonics‐assisted room temperature CO2 stripping and fate of Sono exposed solvent

AbstractBACKGROUNDThe conventional CO2 stripping process in solvent‐based postcombustion CO2 capture (PCCC) process uses heating to strip the CO2 (~120 °C). However, the challenges associated with this method are high energy consumption in degassing the CO2 from solvent, solvent loss and degradation resulting from the high –temperatures, resulting in high energy consumption typical of solvent‐based PCCC. The present study demonstrates the use of bath‐type sonication (470 kHz frequency) to remove CO2 from CO2 loaded 30 wt% Monoethanolamine under controlled temperature conditions. Solvent performance was evaluated following exposure to 2 h conventional heating and 75 h sonication.RESULTSIn a batch sono‐assisted process, CO2 stripping became possible at 17.5 °C compared to 102.2 °C using the conventional method. Increasing the sonication time led decreased carbon loading and increased stripping efficiency. The stripping rate was high at the initial stages of treatment. Evaluation of sono‐exposed solvents exhibited decreased pH during CO2 loading and decreased absorption capacity of the conventionally heated sample.CONCLUSIONThe sono‐assisted method consumes 3.57‐foldless energy than conventional heating. Its CO2 stripping rate was found to be higher within 5 min of sonication. Notably, the maximum temperature reached for the 1 h intervening mode of sonication at 470 kHz was 49.49 °C. The reduction in absorption capacity per hour of conventional heating was 24.5%, whereas for sonication it was <0.4% and solvent loss was 19.7% lower than conventional. There was no significant change in the color, pH and density of the sample. A 20.4% higher surface tension than that of the virgin sample was observed. © 2024 Society of Chemical Industry (SCI).

Extraction and Separation of zirconium using Aliquat 336 from Egyptian black sand

A solvent extraction method has been employed to extract and separate zirconium from the nitric acid medium using 6% tri-caprylmethylammonium chloride (Aliquat 336) [CH3(CH2)7]3N+(CH3) Cl- dissolved in kerosene as diluent. The relevant factors controlling the extraction process of zirconium using Aliquat 336 were studied. These factors include Aliquat 336 concentration, A:O phase ratio, contact time and diluent type. More than 99.6% of Zr was extracted by 6% Aliquat 336 at contact time 10 minutes, phase ratio O:A (v: v) 2:1 and the diluent were kerosene. Third phase formation was studied and dissolving it by using decanol as modifier was also done. Stripping of zirconium from loaded Aliquat 336 has been carried out using 4M H2SO4 as an effective stripping agent. The feasibility of using Aliquat 336 for separation of zirconium was assisted by stripping studies. The loaded zirconium onto Aliquat 336 has been stripped by stripping efficiency 94.18% when using 4M H2SO4 as an efficient eluting agent at 10 minutes contact time and phase ratio O:A (v: v) 1:1.

Separation and Recovery of Palladium (II) and Platinum (IV) from Automotive Catalysts by Solvent Extraction Using Tri-n-butyl Phosphate and Aliquat 336

Pt, Pd, Fe, Ni, and Cr are among the metals found in spent automotive catalysts, which are both environmentally critical and economically beneficial. In this study, solvent extraction methods were utilized to separate and recover palladium (Pd) and platinum (Pt) from wasted car catalyst. The synthetic leach liquor employed in this investigation contains (mg/L): Pd-140, Pt-500, Ni-800, Fe-2000 and Cr-150. The variation of tri-n-butyl phosphate (TBP) in Shellsol D70 from 0.1 to 2 M revealed selective and quantitative Pd extraction even at the lowest extractant concentration. Stripping Pd from loaded organic (LO) phase using 1 M thiourea and 1 M HCl yielded stripping efficiency of 99%. The use of Aliquat 336 at concentrations ranging from 0.05 to 0.5M in the extraction of Pt from Pd free raffinate demonstrated selective extraction of Pt, reaching 99.7% at 0.2M. The use of a McCabe-Thiele plot in 0.2M Aliquat 336 is expected to result in the extraction of more than 99% of Pt in two stages when an A/O phase ratio of 3 is used. The stripping efficiency of Pt from loaded organic (LO) at O/A ratio 6 with 0.5 M thiourea (tu) and HCl was 99.9 percent.

Role of the side chain configuration on the effective recovery of phenolic compounds using polymer inclusion membranes based on tertiary amine

Polymer inclusion membranes (PIMs) exhibit great potential in the separation and recovery of valuable materials from wastewater and secondary resources. In this work, the effect of alkyl chain configuration of the functional carriers on the physicochemical properties and permeability of PIMs was investigated. Three tertiary amine isomers with different alkyl chain configurations were selected as carriers: trioctylamine, triisooctylamine, and tris(2-ethylhexyl)amine. Operating conditions like carrier contents, feed solution pH, phenol concentration, and stripping solution properties were also investigated. The results obtained in this study indicate that tertiary amines with less branched alkyl chains perform better phenol transport efficiency. Furthermore, the transport efficiency decreased rapidly with increasing steric hindrance of the carriers. Trioctylamine-based PIM displayed optimal extraction efficiency of 92.8 % and stripping efficiency of 90.8 % due to its lower steric hindrance, higher hydrophilicity, and larger crystallinity. Phenol extraction and stripping efficiencies remained above 85.7 % and 80.8 % after 8 cycles, demonstrating excellent stability.

Carbon dioxide stripping from acidic wastewater through a vortex venturi tubular microbubble generator

Microbubble generation technology can improve CO2 stripping efficiency while consuming less sweeping gas. In this paper, a vortex venturi tubular microbubble generator is developed based on the concept of “Initial bubble generation with a thin plate type static mixing element” and “Bubble collapse with a venturi channel”. Microbubble characteristics were tested, followed by post-processing of the focused beam reflectance measurement (FBRM) to obtain a multidimensional dataset. The test results indicated that the microbubble quality generated by the vortex venturi tubular microbubble generator was higher than that of the SV-type static mixer. When the gas-liquid volume ratio was 1, the average bubble diameter was 107.05 μm, and microbubbles accounted for 93.29 %. The average bubble diameter of the SV-type static mixer was 473.55 μm, and the proportion of microbubbles was 23.81 % under identical conditions. Furthermore, the CO2 removal efficiency and pH enhancement rate were greatly affected by the gas-liquid volume ratio and the inlet water flow rate, and both fitted an exponential equation correlation. Accordingly, when the gas-liquid volume ratio increased, the quantity of bubbles generated significantly influenced the CO2 stripping efficiency. The stripping efficiency based on the tubular microbubble generator is significantly higher than that of the SV-type static mixer. When the gas-liquid volume ratio was 1, the CO2 removal efficiency was equivalent to that of the SV-type static mixer at a gas-liquid volume ratio of 3.5. When achieving equal CO2 removal efficiency, the gaseous nitrogen consumption of the tubular microbubble generator was 48.61 %-63.30 % lower than that of the SV-type static mixer, and the corresponding energy consumption of the gas compressor was reduced by 38.24 %-55.83 %. The CO2 stripping process based on the vortex venturi tubular microbubble generator offers an environmentally and economically viable treatment option for acid wastewater.

Processing of mineralized microgranite dike for the recovery of niobium, tantalum, and rare earth elements using 1, 2-propyleneglycol extractant

ABSTRACT A number of strategic and economic rare-metal and Rare Earth Elements (REEs)-bearing minerals were recorded in mineralized microgranite dike (MMGD) from Ras Abdah area located in the Northern Eastern Desert of Egypt. Firstly, by sulphuric acid digestion at 300 °C, 3 h, 1/3 ore/Acid ratio, the RE, Nb, and Ta present in the MMGD can be efficiently extracted into the leach solution while Zr, Fe, and Th remained in the unattacked residue. The experimental digestion proved the dissolution of 98.9, 99.2, and 96 % for Nb, Ta, and REEs, respectively. In this study, a novel method was used to selectively recover Nb and Ta content from REEs in the digested concentrate sulphate solution. Solvent extraction using 1, 2-propyleneglycol was applied for the first time to achieve this secondary recovery process. From infrared and 1H-NMR data, the extraction was achieved, and the extractant bonded to Nb and Ta through glycol and alcoholic oxygen atoms. Niobium and Tantalum ions were stripped with water for Ta and 1M HF for Nb, achieving 98.6 and 98.8 % stripping efficiency, respectively. By employing an oxalic acid precipitation technique, a precipitate of extremely pure REEs was extracted from the raffinate solutions.

Reactive extraction of muconic acid by hydrophobic phosphonium ionic liquids - Experimental, modelling and optimisation with Artificial Neural Networks

Muconic acid is a six-carbon dicarboxylic acid with conjugated double bonds that finds extensive use in the food (additive), chemical (production of adipic acid, monomer for functional resins and bio-plastics), and pharmaceutical sectors. The biosynthesis of muconic acid has been the subject of recent industrial and scientific attention. However, because of its low concentration in aqueous solutions and high purity requirement, downstream separation presents a significant problem. Artificial Neural Networks and Differential Evolution were used to optimize process parameters for the recovery of muconic acid from aqueous streams in a system with n-heptane as an organic diluent and ionic liquids as extractants. The system using 120 g/L tri-hexyl-tetra-decyl-phosphonium decanoate dissolved in n-heptane, pH of the aqueous phase 3, 20 min contact time, and 45 °C temperature assured a muconic acid extraction efficiency of 99,24 %. Low stripping efficiency compared to extraction efficiency was observed for the optimum conditions on the extraction step (120 g/L ionic liquids dissolved in heptane). However, re-extraction efficiencies obtained for the recycled organic phase in three consecutive stages were close to the first extraction stage. The mechanism analysis proved that the analysed phosphonium ionic liquids (PILSs) extracts only undissociated molecules of muconic acid through H-bonding.

Removal of calcium from phosphoric acid produced by the nitric acid process using solvent extraction with TCHDGA and stripping with water

The phosphoric acid produced by the nitric acid method cannot be used as an industrial-grade product as a result of the high calcium nitrate content. It can only be used for fertilizer production due to difficulty of complete removal of calcium nitrate. Herein, an efficient approach for the removal of calcium nitrate from the phosphoric acid produced by the nitric acid process was studied. The proposed process is based on solvent extraction with N, N, N′, N′-tetracyclohexyl-3-oxyglutaramide (TCHDGA). The effects of time, diluent, temperature, impurity ions, and the concentrations of extractant and nitric acid on the extraction of Ca2+ were considered. A series of characterization tests involving FT-IR spectroscopy, XPS analysis, slope analysis and X-ray single crystal diffracted analysis revealed that the stoichiometry of the complex is (Ca(NO3)2)(TCHDGA)3. The concentration of Ca2+ in phosphoric acid drops below 5 mg/L a three-stage cross-current extraction process. The stripping efficiency of calcium nitrate in the organic phase by water is above 99.9%. The extraction efficiency of Ca2+ by TCHDGA remained above 96.8% after ten extraction-stripping cycles, realizing the efficient removal of calcium nitrate in the phosphoric acid produced by nitric acid process without changing the traditional production conditions.

Recovery of indium by solvent extraction with crown ether in the presence of KCl and stripping with HCl: A mechanistic study

Hydration of In3+ is the main factor limiting its extraction efficiency from an aqueous solution during a liquid-liquid extraction process. In this study, KCl was introduced into the aqueous solution to facilitate the formation of InCl4− of low charge density, which is expected to possess much weaker hydration compared with In3+, promoting the solvent extraction of indium. The crown ethers (CEs) with varied cavity sizes, benzo-18-crown-6 (B18C6), benzo-15-crown-5 (B15C5), and benzo-12-crown-4 (B12C4), were synthesized. The extraction performance of the CEs toward indium in the presence of sufficient KCl in the aqueous solution was investigated. The liquid-liquid extraction process was analyzed theoretically based on density functional theory (DFT) from the aspects of thermodynamics, geometric structure optimization, electrostatic potential (ESP), and independent gradient model (IGM). The theoretical evaluations agreed well with the experimental results that the hydration of indium could be significantly weakened through the formation of InCl4− and the complexation ability of the CEs toward indium is in the order of B18C6 > B15C5 > B12C4. The complexation mechanism between the CEs and indium during the extraction process was further explored with the assistance of 1H NMR spectrum and SEM-EDS. The results indicate that crown ether coordinates with K+ to form [CE-K]+ at the two-phase interface, which further associates with InCl4− to create the complex of CE-KInCl4, realizing the efficient indium extraction. Moreover, B18C6 showed excellent selectivity toward In3+ over the competing ions such as Fe3+, Al3+, Zn2+, Sn2+ and Ca2+ in a complex system. Indium could be efficiently recovered from the loaded organic phase by using 1 M HCl as the stripping agent with a stripping efficiency of 98.1%.

Production of Perrhenic Acid by Solvent Extraction

The aim of this work was to develop an effective method for obtaining perrhenic acid from available ammonia waste solutions using the solvent extraction method. An ammonia waste solution was used as the test material, with Re and NH4+ concentrations of 13.5 and 43.7 g/dm3, respectively. The scope of this study includes the following: the selection of an appropriate extractant for testing, and the examination of the impact of individual parameters on the efficiency and selectivity of extraction and stripping. The obtained results made it possible to determine the conditions for the production of perrhenic acid via the extraction method using organic solutions of trihexyl(tetradecyl)phosphonium chloride (Cyphos IL 101). The outcome of this study was the development of a method for obtaining perrhenic acid and the production of the acid sample with an efficiency of >90% and a Re concentration of >100 g/dm3.

Sustainable and efficient recovery of lithium from rubidium raffinate via solvent extraction

In recent years, with the increasing prevalence of rechargeable lithium-ion batteries in the burgeoning markets of electric vehicles and portable electronic devices, the consumption of lithium batteries has significantly surged. Hence, the efficient development and utilization of associated lithium resources bear paramount significance. This study aims to recover lithium from rubidium raffinate via solvent extraction. A systematic investigation was conducted to examine the effects of various parameters such as organic phase concentration, contact time, and phase ratio (O/A) during the separation process. The results indicated that the organic phase composed of 0.1 mol/L 4,4,4-Trifluoro-1-phenyl-1,3-butanedione (HBTA) and 0.1 mol/L Trioctylphosphine oxide (TOPO) could efficiently extract lithium from the rubidium raffinate. The optimal conditions were observed at a temperature of 20℃, O/A=1, and a contact time of 5 min. After three-stage countercurrent extraction, a lithium extraction rate of 99.24 % could be achieved, with over 95 % of the sodium easily scrubbed by 0.1 mol/L HCl at an O/A=10. With the use of 3 mol/L HCl, stripping efficiency exceeding 99 % could be attained at an O/A=10, consequently a successful preparation of battery-grade lithium carbonate product was achieved. Regeneration experiments confirmed the organic phase's excellent reproducibility efficiency. Slope analysis and density function theory (DFT) simulations indicated that optimal lithium extraction is achieved when HBTA and TOPO are at equal molar concentrations. The proposed process is expected to provide a green and sustainable route for the recovery of associated lithium resources.

Optimization of thorium solvent extraction process from feed solution with Cyanex 272 by response surface methodology (RSM)

Due to the limited reserves of uranium, the abundance of thorium compared to it and other advantages, the development of the thorium fuel cycle is of interest in different countries. The optimization of thorium extraction from a feed solution produced by Saghand ore with bis(2,4,4-trimethylpentyl) phosphinic acid (Cyanex 272) on a laboratory scale was evaluated by response surface method. The operating variables include Cyanex 272 concentration of 0.001 to 0.2 mol/L, pH of 0 to 2, equilibrium time of 5 to 60 min and aqueous to organic phase ratio of 0.5 to 2.5 were conducted. The value of R2 = 0.9695 and an error of less than 4% indicate the validity of the model. Therefore, the model is in good agreement with the experimental results. It can be said that there are significant interactions between operational parameters, which vindicate different feedbacks of the system in different operational conditions. The results showed that the 4 mol/L sulfuric acid was a suitable agent for recovering thorium ions from the loaded organic phase. In optimum conditions, the thorium purity percentage and thorium stripping efficiency were obtained 98.99 and 94.12%, respectively.

Analisis Penyisihan Kandungan Amonia dengan Stripper di Pabrik Ammonia

Ammonia industrial waste treatment is part of the final process in the industry. Wastewater containing high ammonia content needs to be treated using a stripping process. This study to analysis the stripping process for ammonia waste treatment in the industry to obtain appropriate operating conditions and meet the wastewater standards issued by the Minister of the Environment. Data obtained during 10 days of operation were compared with the standards and analyzed for column efficiency. The results of the analysis showed that the waste output with a concentration of 13.9 - 49 ppm, a pH range of 8.7 - 9 and most of the waste discharge had met the standards, namely a maximum of 50 ppm and pH 6-9. The best gas-liquid ratio at the stripper inlet is 0.25 V / V and pressure has no significant effect on stripper efficiency.

Comprehensive recovery of valuable elements from vanadium precipitation liquor using selective impurity removal-reduction precipitation process

The vanadium precipitation liquor produced by the vanadium slag extraction process contains various valuable elements, which are not utilized at high value. In this paper, chromium is recovered through aluminum salt impurity removal - chemical reduction precipitation method. Moreover, the ammonia nitrogen and sodium sulfur in the vanadium precipitation liquor are recovered by stripping and crystallization, thereby achieving comprehensive resource recovery and utilization. The aluminum salt slag removal reduction chemical precipitation method is used to separate Cr from Si, Ca and V impurities. As a result, the obtained Cr2O3 product has a purity of 98.20%, the chromium recovery efficiency is 97.58%, and the silicon removal efficiency reaches 99.66%. The ammonia nitrogen was recovered by stripping, which would be reused to the vanadium precipitation process, with an ammonia nitrogen stripping efficiency of 98%. The purity of NH4Cl is 99.13% and meets the 99-level national standard. The Na2SO4 was recovered by evaporation concentration - crystallization method, which would be reused to the vanadium slag roasting process, with a Na2SO4 recovery efficiency of 88.38%. And the purity of Na2SO4 is 98.85%, which meets the industrial standard for Class II Na2SO4 products. The final solution after comprehensive recovery of valuable elements would be reused to the leaching process, thereby achieving water circulation. This process realizes the high-value utilization of chromium, ammonia, nitrogen, sodium and sulfur, and has no wastewater discharge and is an environment-friendly route.

Development of a Dual Stripping and Screening Machine for Separating Oil Palm Fruit Bunch

The purpose of this study was to design, fabricate, and evaluate a dual stripping and screening machine for oil palm fruits in Nigeria, with the aim of improving efficiency, reducing damage to the fruits, and minimizing injuries to processors. The study involved the design and fabrication of a machine that could easily handle palm fruit bunches (PFB), separate the fruits from the chaff, and minimize damage to the fruits. The evaluation was conducted using a 3×3×3 factorial experiment, with three levels of PFB sizes, three levels of operating speed, and three replications. The evaluation results showed that the optimal operating speed for the machine was 1000 rpm. At this speed, the machine achieved a stripping efficiency of 98.6% for small PFB sizes, 89.93% for medium PFB sizes, and 85.68% for large PFB sizes. The screening efficiency was 98.62%, 96.23%, and 95.68% for small, medium, and large PFB sizes, respectively. The percentage of damage to the fruits was 2.25%, 2.11%, and 2.55% for small, medium, and large PFB sizes, respectively. The output capacity of the machine was 131.25 kg, 139.30 kg, and 165.36 kg for small, medium, and large PFB sizes, respectively. This study presents a novel dual stripping and screening machine for oil palm fruits, addressing the time-consuming and labor-intensive manual post-harvest operations associated with the local method. The machine's design and evaluation provide valuable insights for improving efficiency and reducing damage in oil palm industries in Nigeria.

Efficient separation and comprehensive recovery of rare earth, bismuth and iron by one-step extraction and two-step stripping

A route was proposed to separate bismuth, iron, and rare earth elements from a solution containing nickel and magnesium through one-step extraction and two-step stripping. Firstly, saponified di-(2-ethylhexyl) phosphoric acid (D2EHPA) was used as the extractant to separate target elements. RE(III), Bi(III), and Fe(III) could be separated from Ni(II) and Mg(II), with extraction efficiencies of more than 99 %. Secondly, RE(III), Bi(III), and Fe(III) were stripped selectively by nitric acid and oxalic acid, respectively. Subsequently, the iron present in the oxalic acid stripping solution was treated under UV irradiation for 15 min to recover oxalic acid and obtain the ferrous oxalate product. The stripping efficiencies of RE(III), Bi(III), and Fe(III) were up to 100 % for four-stage countercurrent stripping, and the recovery rates of RE(III) and Bi(III) were 97.3 % and 99.2 %. The purities of nitrate rare earth enrichment solution, bismuth oxalate and ferrous oxalate were 99.7 %, 98.4 % and 99.5 %, respectively. In addition, the extraction dynamic demonstrated that the double salt precipitation was not observed during the extraction when the extraction time exceeded 7 min and the extraction mechanism was analyzed using the slope method. This process shortens steps, and is more efficient to separate RE(III), Bi(III), and Fe(III) from the mixed solution containing Ni(II) and Mg(II), which has a prospective industrial application.

From waste to added-value product: A case of efficient separation and recovery of zinc and iron from spent galvanizing acid

Spent galvanizing acid solution contains high concentrations of zinc salts, ferrous salts, and residual acids, exhibiting extremely high value-added recovery potential. However, achieving the efficient extraction and separation of Zn over Fe becomes particularly challenging under elevated Zn ion concentration. Here, the key extraction parameters, such as modifier ratio, Cyanex 923 concentration and ratio of organic phase to aqueous phase (O/A), are investigated. The stripping and regeneration of extractant, extraction mechanism, as well as high-value recovery of Zn and Fe resources are also comprehensively expounded. After the two-stage extraction, the extraction efficiency of Zn and Fe is 98.92 ​% and 2.09 ​%, respectively. Moreover, the stripping efficiency of Zn reaches 92.3 ​% with O/A ratio of 1 : 2, using oxalic acid as stripping agent. The predominant extracted species is confirmed to be ZnCl3−, resulting in the formation of HZnCl3∙R3PO complex. More importantly, the regenerated extractant can be recycled back into the extraction process, and the reproduced HCl, high-value recovered ZnO and Fe2O3 can be used for different industrial fields. These findings lay a solid foundation for the efficient separation and comprehensive recovery of high-concentration spent galvanizing acid solution.

Separation of vanadium, tungsten, and arsenic from alkaline leachate of spent SCR catalysts via coextraction and stepwise stripping

The application of sodium hydroxide solution in the treatment of spent SCR catalysts has emerged as a prevalent technique for the recovery of titanium dioxide. Nonetheless, this method yields a substantial quantity of wastewater containing vanadium, tungsten, and arsenic, posing significant challenges for recycling, and resulting in the unnecessary disposal of valuable metals. In this study, the separation of vanadium, tungsten, and arsenic from alkaline leachate of spent SCR catalysts was investigated using modified Aliquat 336 with SO42− (MA336-S). Firstly, 98.88 % and 97.93 %, and 13.27 % of vanadium, tungsten, and arsenic were coextracted by MA336-S, and the electrospray ionization mass spectrometry and fourier transform infrared spectroscopy were employed to verify the formation of [(R3CH3N)2HVO4] and [(R3CH3N)2WO4]. Afterwards, the effective separation of vanadium, tungsten, and arsenic in organic phase was achieved by stepwise stripping. When Na2SO4 was used as the stripping agent, the stripping efficiency for arsenic reached 96.06 %. The selective stripping of vanadium and tungsten was achieved using 2.5 M NaOH and 1 M Na2SO4 + 1 M NaOH, respectively, resulting in stripping ratios of 99.59 % for vanadium and 99.15 % for tungsten. An extremely high separation factor of vanadium and tungsten (βV/W, 2388) can be achieved. Subsequently, the organic phase was preserved for recycling. A comprehensive process flowsheet was clarified for the efficient separation of vanadium, tungsten, and arsenic from the alkaline leachate of spent SCR catalysts, thereby facilitating a synergistic and enhanced recovery of these valuable metals from waste resources.