scholarly journals Extraction Equilibrium of Ni(II) in the Ni2+-SO42--Ac-(Na+, H+) - Cyanex 272 (H2A2)-kerosene-3%(v/v) Octan-1-ol System

2011 ◽  
Vol 4 (1) ◽  
pp. 83 ◽  
Author(s):  
R. K. Biswas ◽  
A. K. Karmakar ◽  
M. S. Rahman
Keyword(s):  
Distribution Ratio ◽  
Extraction Process ◽  
Equilibration Time ◽  
High Concentration ◽  
Concentration Region ◽  
Extraction Equilibrium ◽  
Cyanex 272 ◽  
Maximum Loading ◽  
Constant Ph ◽  
Title System

The title system has been studied elaborately. 3% (v/v) octan-1-ol is added as de-emulsifier. Equilibration time is < 2 min. Distribution ratio (D) at constant pH(eq) and [H2A2] is independent of [Ni(II)](aq). The pH dependency is always found to be 2; whilst the extractant dependence is found to vary from 1 (at lower concentration region, lcr) to 3 (at high concentration region, hcr). Moreover, the distribution ratio is found to be inversely proportional to (1+6.92 [SO42-]) and [Ac-]. Based on these results, the extraction equilibrium reactions have been proposed at various parametric conditions. The extraction process is endothermic (?H = 54.66 kJ/mol). The Kex values at 303 K are evaluated to be 10-11.086 and 10-11.56 at lcr and hcr of extractant, respectively. The maximum loading capacity is 21.28 g Ni(II) per 100 g extractant indicating the formation of NiAcA at maximum loading. The stripping ability of various inorganic acids towards loaded nickel, as well as, the possibilities of separation of Ni(II) from its binary mixtures with other ions of 3d-block elements have also been investigated.Keywords:  Extraction equilibrium; Ni(II) extraction; Cyanex 272; Sulphate-acetato medium; Kerosene-octanol.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i1.8007J. Sci. Res. 4 (1), 83-97 (2012) 

scholarly journals Solvent Extraction of Fe(III) from Aqueous Chloride Solution by Cyanex 301 Dissolved in Kerosene

2010 ◽  
Vol 3 (1) ◽  
pp. 97 ◽  
Author(s):  
R. K. Biswas ◽  
M. R. Ali ◽  
M. A. Habib ◽  
S. M. A. Salam ◽  
A. K. Karmakar ◽  
...  
Keyword(s):  
Equilibration Time ◽  
Extractant Concentration ◽  
Extraction Equilibrium ◽  
Wide Range ◽  
Aqueous Chloride Solution ◽  
Title System ◽  
Aqueous Chloride ◽  
Cyanex 301 ◽  
Extraction Mechanisms ◽  
Aqueous Acidity

The title system has been investigated over a wide range of aqueous acidity. The equilibration time is 1 h. The extraction ratio (D) is independent of [Fe(III)] provided equilibrium [HCl] and [HA] are kept constant. At a constant equilibrium extractant concentration, the [HCl] dependences are -1.6, ~0 and -3 in the [HCl] regions of >3, 2-0.5 and <0.3 M; respectively; whilst at constant [HCl], the [HA] dependence is 3.0. On the other hand, [Cl-] dependence varies within -0.5 to -3 at constant [HCl] of 0.3 M; whereas its values are ~ -1 and ~ 0.63 at constant [HCl] of 3 and 1 M, respectively. Based on these results the extraction mechanisms have been suggested to be + 3 HA(o) ? FeA3(o) + n Cl- + 3 H+ in the low [HCl] region,    + 3 HA(o) + n Cl- ? FeCl3.3HA(o) in the intermediate [HCl] region and HFeCl4 + 3 HA(o) ? FeCl3.3HA(o) + HCl in the high [HCl] region under investigation. The Kex  and ΔH values have been evaluated. Loading capacity is 5.5 g Fe(III)/100 g Cyanex 301. The stripping can be made effective by a mixture of 6 M H2SO4 and 1 M Na2C2O4.Keywords:  Extraction equilibrium; Fe(III) extraction; Cyanex 301; chloride medium.© 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi:10.3329/jsr.v3i1.6263                 J. Sci. Res. 3 (1), 97-109 (2011)

scholarly journals Counter-Current Suspension Extraction Process of Lignocellulose in Biorefineries to Reach Low Water Consumption, High Extraction Yields, and Extract Concentrations

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1585
Author(s):  
Marc Conrad ◽  
Irina Smirnova
Keyword(s):  
Water Consumption ◽  
Potential Method ◽  
Extraction Process ◽  
High Yield ◽  
Process Window ◽  
Equilibration Time ◽  
High Concentration ◽  
Wastewater Disposal ◽  
Pretreated Wheat Straw ◽  
Counter Current

The processing of large quantities of water in biorefining processes can lead to immense costs for heating, evaporation, and wastewater disposal. These costs may prohibit the exploitation of alternative products, e.g., xylooligosaccharides from straw, which are regarded as too costly. A new counter-current extractions method is proposed that aims at low solvent (water) consumption, as well as high yields and extract concentrations. This process was evaluated with suspension extraction experiments with steam pretreated wheat straw and the process window analysis based on a mass balance for a washing and a leaching scenario. The latter was conducted with two other suspension extraction processes as a comparison. The equilibration time was found to be well below 10 min. While the suspension extraction with and without recycling need to be designed to achieve a high yield or a high concentration and low solvent consumption, the proposed extraction method can reach all three simultaneously. Thus, this new process is evaluated as a potential method to spare water and downstream costs and allow new processing pathways in second-generation biorefineries.

Treatment of strong nitrogen swine wastewater in a full-scale sequencing batch reactor

2004 ◽  
Vol 49 (5-6) ◽  
pp. 315-323 ◽  
Author(s):  
K.M. Poo ◽  
B.H. Jun ◽  
S.H. Lee ◽  
J.H. Im ◽  
H.J. Woo ◽  
...  
Keyword(s):  
Batch Reactor ◽  
P Uptake ◽  
Full Scale ◽  
Swine Wastewater ◽  
High Concentration ◽  
Effluent Quality ◽  
Loading Rates ◽  
Maximum Loading ◽  
Swine Urine

Treatment of swine wastewater containing strong nitrogen was attempted in a full-scale SBR. The strongest swine wastewater was discharged from a slurry-type barn and called swine-slurry wastewater (SSW). Slightly weaker wastewater was produced from a scraper-type barn and called swine-urine wastewater (SUW). TCOD, NH4+-N and TSS in raw SSW were 23,000-72,000 mg/L, 3,500-6,000 mg/L and 17,000-50,000 mg/L, respectively. A whole cycle of SBR consists of 4 sub-cycles with anoxic period of 1 hr and aerobic period of 3 hr. The maximum loading rates of both digested-SSW and SUW were similar to 0.22 kg NH4+-N/m3/day whereas the maximum loading rates of raw SSW was up to 0.35 TN/m3/day on keeping the effluent quality of 60 TN mg/l. The VFAs portion of SCOD in raw SSW was about more than 60%. The VFAs in SUW and digested-SSW were about 22% and 15%, respectively. NH4+-N and PO43--P in SSW were removed efficiently compared to those in digested-SSW and DUW because SSW had high a C/N ratio and readily biodegradable organic. High concentration of organic was useful to enhance denitrification and P uptake. Also the amount of external carbon for denitrification was reduced to 5% and 10% of those for digested-SSW and SUW.

scholarly journals Investigation of the extraction equilibrium of ion-association complexes of molybdenum (VI) with some polyphenols and thiazolyl blue. extraction-spectrophotometric determination of molybdenum

2005 ◽  
Vol 3 (4) ◽  
pp. 747-755 ◽  
Author(s):  
Atanas Dimitrov ◽  
Vania Lekova ◽  
Kiril Gavazov ◽  
Boyan Boyanov
Keyword(s):  
Organic Solvent ◽  
Aqueous Medium ◽  
Spectrophotometric Method ◽  
Ion Association ◽  
Extraction Process ◽  
Association Constants ◽  
Optimum Conditions ◽  
Extraction Equilibrium ◽  
Simple Extraction

AbstractThe extraction process of ternary ion-association complexes of molybdenum (VI) with some polyphenols (4-nitrocatechol, 2,3-dihydroxy naphthalene) and thiazolyl blue has been investigated by using an extraction-spectrophotometric method. The optimum conditions for their quantitative preparation in aqueous medium and subsequent extraction into an organic solvent have been found. The extraction, distribution and association constants, and the recovery factors have been calculated. The composition of the complexes has been determined. A precise, sensitive and simple extraction-spectrophotometric method for determination of molybdenum in products from ferrous metallurgy has been developed.

Numerical Simulation on Hydrogen Dispersion in Automobiles due to Storage Cylinder Failure

2011 ◽  
Author(s):  
Yan-Lei Liu ◽  
Jin-Yang Zheng ◽  
Shu-Xin Han ◽  
Yong-Zhi Zhao
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Numerical Model ◽  
Hydrogen Sensor ◽  
High Concentration ◽  
Concentration Region ◽  
Species Transport ◽  
Safety Design ◽  
Simulation Results

A numerical model for dispersion of hydrogen in hydrogen powered automobiles was established basing on finite element method with species transport and reaction module of FLUENT. And corresponding numerical simulations were done in order to analysis the dispersion of hydrogen due to leakage from different position of the storage cylinder on the automobiles. Also, the distribution of the hazard region due to hydrogen dispersion was obtained. The simulation results show that the baffle above the cylinder can accumulate the hydrogen. Therefore, the high concentration region of hydrogen exists near the baffle. The study can provide reference for hydrogen sensor placement and safety design of hydrogen powered automobiles.

scholarly journals The Effect of Operating Conditions on Curcumin Extracted from Turmeric by Hydrothermal Extraction

2019 ◽  
Vol 125 ◽  
pp. 19001
Author(s):  
Mohamad Endy Yulianto ◽  
Rizka Amalia ◽  
Vita Paramita ◽  
Indah Hartati ◽  
Nissa Ayu Maulinda ◽  
...  
Keyword(s):  
High Efficiency ◽  
Economic Value ◽  
Bioactive Compound ◽  
Extraction Process ◽  
Operating Conditions ◽  
Extraction Temperature ◽  
Liquid Ratio ◽  
High Concentration ◽  
Solid Liquid ◽  
Hydrothermal Extraction

Turmeric has a bioactive compound namely curcuminoid. It has many pharmacology effects such as anticancer, antidiabetic, antioxidant, hypolipidemic, anti-inflammatory, antimicrobial, antifertility, anti-venom, anti-coagulant, anti-HIV hepatoprotective, nephroprotective, and anticoagulant properties. To increase the economic value of turmeric, it is necessary to develop a hydrothermal extraction process of turmeric’s active compound. The advantages of hydrothermal extraction were inexpensive, abundant availability, high purity, non-toxic, and easy to handle. This research aims to study the effect of operating conditions : temperature (130-150oC), time (10-40 minutes) and solid:liquid ratio (1:10 and 1:12) on the bioactive compounds of turmeric extracted from hydrothermal extraction process. Generally, high extraction yield was obtained at higher extraction temperature (140 and 150oC). Under these conditions, with a lower solid : liquid ratio (1:10), high concentration of curcumin is produced. Further, a higher solid : liquid ratio will likely produce the opposite result, except when it operates at low extraction temperature. The high temperature of the pressurized liquid water can reduce the viscosity and surface tension of water so it will increase the diffusion rates and absorption. The higher the solid:liquid ratio, the greater the different concentration between interior and exterior cell, which promote the high efficiency of diffusion process.

Thermodynamics of Solvent Extraction of Perrhenate with N235 at High Concentration

2010 ◽  
Vol 150-151 ◽  
pp. 890-894
Author(s):  
Ke Xu Jiang ◽  
Da Wei Fang ◽  
Han Wang ◽  
Bao Xin Wang ◽  
Ying Xiong ◽  
...  
Keyword(s):  
Solvent Extraction ◽  
Aqueous Phase ◽  
Supporting Electrolyte ◽  
Extraction Process ◽  
Extraction System ◽  
Thermodynamic Quantities ◽  
High Concentration ◽  
Extraction Constants ◽  
Solvent Extraction System

In solvent extraction system of perrhenate with the extractant of N235 at high concentration, the equilibrium molalities of ReO4- were measured at ionic strengths from 0.2 to 2.0 mol.kg-1 in the aqueous phase containing Na2SO4 as the supporting electrolyte from 278.15K to 303.15K. The standard extraction constants K0 at various temperatures were obtained. Thermodynamic quantities for the extraction process were also calculated.

Heat capacities and volumes of NaCl, MgCl2, CaCl2, and NiCl2 up to 6 molal in water

1981 ◽  
Vol 59 (21) ◽  
pp. 3049-3054 ◽  
Author(s):  
Gèrald Perron ◽  
Alain Roux ◽  
Jacques E. Desnoyers
Keyword(s):  
Aqueous Solutions ◽  
Long Range ◽  
Higher Order ◽  
Heat Capacities ◽  
Range Order ◽  
Long Range Order ◽  
High Concentration ◽  
Concentration Region ◽  
Partial Molar Heat Capacities ◽  
High Concentrations

It has been claimed by Enderby and co-workers that changes in long-range order occur in NiCl2 aqueous solutions at high concentrations. To investigate the possibility of a transition, the partial molar heat capacities and volumes of NiCl2, CaCl2, MgCl2, and NaCl were measured and compared in water at 25 °C up to 6 mol kg−1. In the case of NaCl, data were also measured at 5 and 45 °C. A slight change in slope of [Formula: see text] is observed for NiCl2 around 4 mol kg−1 which may suggest a third or higher order transition. However, the change is too small to support unambiguously any particular model for the high concentration region.

scholarly journals Factorial (25) design for the extraction of V(IV) in the V(IV)-[SO42-](H+, Na+) ? Cyanex 302-kerosene system

2016 ◽  
Vol 51 (1) ◽  
pp. 47-54
Author(s):  
RK Biswas ◽  
AK Karmakar
Keyword(s):  
Regression Model ◽  
Factorial Design ◽  
Interaction Effect ◽  
Model Equation ◽  
Equilibration Time ◽  
Factors Affecting ◽  
Cyanex 302 ◽  
Title System ◽  
Points Of View ◽  
Full Factorial

The title system has been investigated from the modeling points of view. Equilibration time is 20 min and the significant extraction occurs above pH 2. Considering the constancy of the organic to aqueous phase ratio (1:1), the factors affecting the extent of extraction (value of log D or log CD) are [V(IV)], pH(eq), [Cyanex 302], [SO42-] and temperature (T). The levels of these factors chosen in experimentation are high (+) and low (-). Regression or model equation for the extraction of vanadium (IV) by Cyanex 302 is determined from 25 full factorial design. On abbreviating log[V(IV)], -log(1+4641.14x10-pH + (1.5x106)x10-2pH), log[Cyanex 302], -log(1+2.24 [SO42-]) and absolute temperatures as M, P, E, S and T, respectively, the model obtained is: log CD = 10.452-0.16M+1.0047P+2.0011E+1.0003S-2425.3729/T. From the regression model it is seen that there is no interaction effect between the factors under investigation. The model can describe the system well.Bangladesh J. Sci. Ind. Res. 51(1), 47-54, 2016

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