scholarly journals Kinetics analysis of the forward extraction of cerium(III) by D2EHPA from chloride medium in the presence of two complexing agents using a constant interfacial area cell with laminar flow

2018 ◽  
Vol 7 (4) ◽  
pp. 380-386 ◽  
Author(s):  
Jiannan Pei ◽  
Junwen Zhou ◽  
Feng Jiang ◽  
Kaihua Chen ◽  
Shaohua Yin ◽  
...  
Keyword(s):  
Laminar Flow ◽  
Interfacial Reaction ◽  
Rate Equation ◽  
Ph Value ◽  
Kinetic Studies ◽  
Interfacial Area ◽  
Extraction Process ◽  
Extraction Rate ◽  
Complexing Agents ◽  
Specific Interfacial Area

Abstract The kinetic studies performed on the forward extract of cerium(III) from chloride solution with the complex agents, citric acid (H3Cit) and lactic acid (HLac) in the presence of di-(2-ethylhexyl)phosphoric acid (D2EHPA, H2A2) have been investigated using a constant interfacial area cell with laminar flow. The effects of stirring speed, temperature, and specific interfacial area on the extraction rate are discussed separately, and the results show that the extraction process is a diffusion-controlled kinetics process with an interfacial reaction. Studies on the effect of pH value and H2A2 concentration on the extraction rate are used to obtain the rate equation. The rate-controlling step is also suggested by the predictions derived from the interfacial reaction models, and the rate equation obtained by the kinetic model is consistent with that obtained by the experimental results. The information on the extraction kinetics in this extraction system will provide some knowledge of its application.

Extraction Kinetics of Cerium(III) from Chloride Medium by Di-(2-Ethylhexyl)phosphoric Acid in the Presence of Acetic Acid Using a Constant Interfacial Area Cell with Laminar flow

2012 ◽  
Vol 482-484 ◽  
pp. 2204-2209 ◽  
Author(s):  
Hong Tao Chang ◽  
Mei Li ◽  
Zhao Gang Liu ◽  
Yan Hong Hu ◽  
Fu Shun Zhang
Keyword(s):  
Acetic Acid ◽  
Laminar Flow ◽  
Phosphoric Acid ◽  
Interfacial Area ◽  
Extraction Process ◽  
Effect Of Temperature ◽  
Complexing Agent ◽  
Extraction Kinetics ◽  
Specific Interfacial Area ◽  
Diffusion Controlled

The Ce(III) extraction kinetics with di-(2-ethylhexyl)phosphoric acid (D2EHPA) in the presence of a complexing agent acetic acid(HAc) has been investigated using constant interfacial cell with laminar flow. The kinetics mechanism and extraction rate equation were achieved by the studies on the effect of stirring rate, temperature and specific interfacial area on the rate of extraction. The effect of temperature on the kinetics was analyzed, the value of the apparent activation energy was calculated as 11.96 kJ/mol, and it was found that the extraction process was a diffusion-controlled kinetics regime.

Extraction Kinetics and Mechanism of La(III) by P204-Kerosine from Phosphoric Acid

2014 ◽  
Vol 881-883 ◽  
pp. 677-682 ◽  
Author(s):  
Yun Shan Xiao ◽  
Ya Gu Dang ◽  
De Jun Fei ◽  
Ying Zhang
Keyword(s):  
Phosphoric Acid ◽  
Interfacial Area ◽  
Extraction Process ◽  
Kinetics And Mechanism ◽  
Extraction Rate ◽  
Extraction Kinetics ◽  
Interface Area ◽  
Plateau Region ◽  
Specific Interface Area ◽  
Mixed Mechanism

The extraction kinetics and mechanism of La (III) by P204-kerosine from phosphoric acid were investigated by constant interfacial cell with laminar flow. The effects of stirring speed, temperature, specific interface area on extraction rate were studied. The results indicated that a plateau region is appeared at the stirring speed of over 115r/min. The extraction apparent activation energy was calculated to be-13.40kJ/mol and the extraction process is controlled by a mixed mechanism of diffusion and chemical reaction. The rate equation of extraction was deduced. Under conditions of 25°C and interfacial area 19.64cm2, the extraction rate constant was 2.08×10-6 m·s-1·. Through the derivation of the reaction mechanism the reaction zone is at the liquid-liquid interface.

Study on Mass-Transfer Kinetics of Nd by 2-Ethylhexylphosphonic Acid Mono-(2-Ehylhexyl) Ester in the Presence of a Complexing Agent

2012 ◽  
Vol 461 ◽  
pp. 647-651
Author(s):  
Hong Tao Chang ◽  
Mei Li ◽  
Zhao Gang Liu ◽  
Yan Hong Hu ◽  
Fu Shun Zhang
Keyword(s):  
Interfacial Area ◽  
Extraction Process ◽  
Effect Of Temperature ◽  
Complexing Agent ◽  
Extraction Kinetics ◽  
Specific Interfacial Area ◽  
Diffusion Controlled ◽  
Mass Transfer Kinetics ◽  
Kinetics Of ◽  
Rate Of Extraction

The Nd(III) extraction kinetics by 2-ethylhexylphosphonic acid mono-(2-ethylhexyl) ester (HEH/EHP) in the presence of a complexing agent acetic acid(HAc) has been investigated using constant interfacial cell. The kinetics mechanism and extraction rate equation were achieved by the studies on the effect of stirring rate, temperature and specific interfacial area on the rate of extraction. The effect of temperature on the kinetics was analyzed, the value of the apparent activation energy was calculated as 9.24 kJ/mol, and it was found that the extraction process was a diffusion-controlled kinetics process.

scholarly journals Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2518
Author(s):  
Dorota Kołodyńska ◽  
Yongming Ju ◽  
Małgorzata Franus ◽  
Wojciech Franus
Keyword(s):  
Experimental Data ◽  
Aspartic Acid ◽  
Ph Value ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Modified Zeolite ◽  
X Ray ◽  
Slow Release Fertilizers ◽  
Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

scholarly journals Separation of Sn, Sb, Bi, and Cu from Tin Anode Slime by Solvent Extraction and Chemical Precipitation

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 515
Author(s):  
Wei-Sheng Chen ◽  
Shota Mesaki ◽  
Cheng-Han Lee
Keyword(s):  
Solvent Extraction ◽  
Liquid Phase ◽  
Ph Value ◽  
Chemical Precipitation ◽  
Extraction Process ◽  
Refining Process ◽  
Anode Slime ◽  
Electrolytic Refining ◽  
Precipitation Procedure ◽  
Tin Anode

Tin anode slime is a by-product of the tin electrolytic refining process. This study investigated a route to separate Sn, Sb, Bi, and Cu from tin anode slime after leaching with hydrochloric acid. In the solvent extraction process with tributyl phosphate, Sb and Sn were extracted into the organic phase. Bi and Cu were unextracted and remained in the liquid phase. In the stripping experiment, Sb and Sn were stripped and separated with HCl and HNO3. Bi and Cu in the aqueous phase were also separated with chemical precipitation procedure by controlling pH value. The purities of Sn, Sb, Cu solution and the Bi-containing solid were 96.25%, 83.65%, 97.51%, and 92.1%. The recovery rates of Sn, Sb, Cu, and Bi were 76.2%, 67.1%, and 96.2% and 92.4%.

Optimization of the Extraction Technology and Assessment of Antioxidant Activity of Chlorogenic Acid-Rich Extracts From Eucommia ulmoides Leaves

2021 ◽  
Vol 16 (10) ◽  
pp. 1934578X2110461
Author(s):  
Hua Jiang ◽  
Jun Li ◽  
Ning Zhang ◽  
Hai-Yang He ◽  
Jia-Min An ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Chlorogenic Acid ◽  
Ph Value ◽  
Extraction Process ◽  
Eucommia Ulmoides ◽  
Extraction Technology ◽  
Dpph Method ◽  
Contour Plots ◽  
Technology And Assessment ◽  
Design Optimum

Chlorogenic acid has been proved to have cardiovascular protection, antibacterial, antiviral, hemostatic, and hypolipidemia effects. Modern scientific research on the bioactivity of chlorogenic acid has been extended to the fields of food, medicine, health care and daily-use chemical industry. The aim of this research was to optimize the extraction conditions for chlorogenic acid from Eucommia ulmoides (Eucommiaceae) leaves. The significant variables were screened and optimized by a combination of Plackett-Burman test and Box-Behnken design. Optimum extraction parameters with ethanol concentration of 50%, solvent pH value of 3, and particle size of 60 mesh were determined according to variance analysis and contour plots. Under these conditions, the yield of chlorogenic acid was up to 4.36 mg/g, which was basically consistent with the theoretical prediction value of 4.50 mg/g. This study also proved the potential antioxidant activity of E. ulmoides leaves. The optimal extract of E. ulmoides leaves rich in chlorogenic acid showed the highest antioxidant activity in the FRAP method, which was 219.8 μM Trolox equivalents (TE) per g extract weight (EW) (μM TE/g EW). The DPPH method gave a similar value (168 μM TE/g EW) to the ABTS method (152 μM TE/g EW). The established extraction process was efficient in the recovery of chlorogenic acid from E. ulmoides leaves, encouraging its valorization as a cheap and sustainable alternative for the isolation of chlorogenic acid.

Modeling Two-Phase Flow in Porous Media Including Fluid-Fluid Interfacial Area

2008 ◽  
Author(s):  
Jennifer Niessner ◽  
S. Majid Hassanizadeh ◽  
Dustin Crandall
Keyword(s):  
Porous Media ◽  
Capillary Pressure ◽  
Two Phase Flow ◽  
Interfacial Area ◽  
Flow In Porous Media ◽  
Extended Model ◽  
Phase Flow ◽  
Two Phase ◽  
Specific Interfacial Area ◽  
Macro Scale

We present a new numerical model for macro-scale two-phase flow in porous media which is based on a physically consistent theory of multi-phase flow. The standard approach for modeling the flow of two fluid phases in a porous medium consists of a continuity equation for each phase, an extended form of Darcy’s law as well as constitutive relationships for relative permeability and capillary pressure. This approach is known to have a number of important shortcomings and, in particular, it does not account for the presence and role of fluid–fluid interfaces. An alternative is to use an extended model which is founded on thermodynamic principles and is physically consistent. In addition to the standard equations, the model uses a balance equation for specific interfacial area. The constitutive relationship for capillary pressure involves not only saturation, but also specific interfacial area. We show how parameters can be obtained for the alternative model using experimental data from a new kind of flow cell and present results of a numerical modeling study.

The characterization of crystalline particle growth in TiNi thin films

2004 ◽  
Vol 37 (6) ◽  
pp. 1007-1009 ◽  
Author(s):  
Yonghua Li ◽  
Fanling Meng ◽  
Jinkuan Wang ◽  
Yuming Wang
Keyword(s):  
Interfacial Area ◽  
Particle Growth ◽  
Radius Of Gyration ◽  
Phase System ◽  
Crystalline Particle ◽  
Two Phase ◽  
X Ray ◽  
Specific Interfacial Area ◽  
Subsequent Decrease ◽  
Sputter Deposited

Small-angle X-ray scattering (SAXS) and X-ray diffraction (XRD) have been used to investigate sputter-deposited TiNi films annealed at 773 K for 3, 8, 13, 15, 25 and 60 min. The specific interfacial area of the crystalline–amorphous two-phase system increases at the beginning of annealing, achieves a maximum after about 13 min and decreases on further annealing, whereas the radius of gyration of the crystalline particle increases during the annealing process. The prominent increase of the specific interfacial area and the slight increase of the radius of gyration of the crystalline particle at the beginning of annealing are correlated with the nucleation of the crystalline particle. The subsequent decrease of the specific interfacial area is correlated with the growth of the crystalline particles.

Sign in / Sign up

Export Citation Format

Share Document