scholarly journals Equilibrium Study on Reactive Extraction of Lactic Acid with Tri-n – Butyl Phosphate in n - Hexane

2013 ◽  
Vol 12 (2) ◽  
pp. 1
Author(s):  
Panut Mulyono ◽  
Anita Pardah
Keyword(s):  
Aqueous Solution ◽  
Lactic Acid ◽  
Ambient Temperature ◽  
Carboxylic Acids ◽  
Distribution Ratio ◽  
Equilibrium Constants ◽  
Reactive Extraction ◽  
Extraction Temperature ◽  
Process Selection ◽  
Initial Concentration

Extraction of carboxylic acids from dilute aqueous solution using traditional solvents such as ketones, alcohols, ethers, and ester is inefficient because the distribution ratio is rather low. Reactive extraction which exploits reversible chemical complexation is an effective separation process for extraction of carboxylic acids from aqueous streams such as fermentation broths and wastewaters. In the extraction process, selection of the solvent is an important aspect to be considered. Considering its solubility in water, cost and availability, tri-n-butyl phosphate (TBP) seems to be an attractive solvent for the extraction of lactic acid from aqueous solution. The purpose of this experiment is to study the equilibrium of the reactive extraction of lactic acid in aqueous solution with TBP in n-hexane. The parameters studied in this experiment were initial concentration of lactic acid in the aqueous phase, TBP concentration in n-hexane phase, and the extraction temperature. The experiments at ambient temperature were carried out using a separatory funnel, while the experiments at other than ambient temperature were carried out using erlenmeyer flask and water bath shaker to adjust the temperature. In this experiment, the initial concentration of lactic acid was varied from 0.1 to 0.5 gmol/dm3. The range of initial TBP concentrations in n-hexane was 0.1 to 1.0 gmol/dm3 and the extraction temperature range was 283 to 313 K. The experimental results showed that the higher the initial concentration of lactic acid in aqueous solution, the higher the distribution ratio for a fixed TBP concentration and extraction temperature. For a fixed initial concentration of lactic acid in aqueous solution and extraction temperature, the distribution ratio of lactic acid is increased by increasing TBP concentration. The overall equilibrium constants (Kpq) for the experiments using TBP concentration ranging from 0.1 to 1.0 gmol/dm3 at the extraction temperature of 293 K are calculated to be 0.0668 to 0.5144. Kpq for the experiments at the temperature ranging from 283 to 313 K at the initial concentration of lactic acid of 0.2 gmol/L are found to be 0.0122 to 0.8856. The Kpq as a function of temperature (T) in K can be expressed as ln Kpq = 10,596/T - 38.08 with sum of square of error of 0.14.

Acid Ionizations of Nitroalkanes in Aqueous Solution

1973 ◽  
Vol 51 (12) ◽  
pp. 1941-1944 ◽  
Author(s):  
Takeki Matsui ◽  
Loren G. Hepler
Keyword(s):  
Aqueous Solution ◽  
Carboxylic Acids ◽  
Equilibrium Constants ◽  
Free Energies ◽  
Methyl Substitution ◽  
Calorimetric Measurements ◽  
Acid Ionizations

Calorimetric measurements have led to ΔH0 values for ionization of nitromethane, nitroethane, 1-nitropropane, and 2-nitropropane in aqueous solution at 298°K. Combinations of these enthalpies with free energies from equilibrium constants for ionization have led to ΔS0 values for the ionization reactions. It is noted that the trend toward decreasing pK with methyl substitution in nitroalkanes is unusual compared to phenols and carboxylic acids. Similarly, correlations of ΔS0 with ΔG0 and ΔH0 are different for nitroalkanes than for other acids.

Thermodynamic Analysis of Trace Cobalt(II) Extraction from Cobalt Chloride Aqueous Solution Using Cyanex 272 in Kerosene

2021 ◽  
Vol 16 (2) ◽  
pp. 249-254
Author(s):  
Zhi-Qiang Ning ◽  
Chun-Yuan Sang ◽  
Jia-Hui Liu ◽  
Hong-Wei Xie ◽  
Qiu-Shi Song ◽  
...  
Keyword(s):  
Distribution Ratio ◽  
Ph Value ◽  
Equilibrium Constants ◽  
Chloride Ion ◽  
Ion Concentration ◽  
Extraction Temperature ◽  
Extractant Concentration ◽  
Cyanex 272 ◽  
Different Temperatures ◽  
The Relationship

In this study, it was researched that the extraction of Co(II) from CoCl2 aqueous solutions using Cyanex 272 (bis(2,4,4-trimethylpentyl) phosphonic acid) in kerosene and determined the effects of the equilibrium pH value, extractant concentration and chloride ion concentration on the extraction of cobalt at different temperatures. The results indicate that the distribution ratio of cobalt increases as the equilibrium pH value, extractant concentration and extraction temperature increase. However, the cobalt distribution ratio decreases as the chloride ion concentration increases. We calculated the equilibrium constants (AH9, AG9, and AS9) for a range of temperatures and investigated the relationship between AG9 and T. The extraction reaction of cobalt was determined to be an endothermic reaction; thus, raising the temperature was beneficial to the reaction.

scholarly journals Reactive Extraction of levulinic acid using tri-n-Octylamine in 1-hexanol

2019 ◽  
Vol 9 (2) ◽  
pp. 4534-4539
Keyword(s):  
Aqueous Solution ◽  
Levulinic Acid ◽  
Room Temperature ◽  
Extraction Efficiency ◽  
Reactive Extraction ◽  
Chemical Extraction ◽  
Initial Concentration ◽  
Equilibrium Data ◽  
Loading Ratio ◽  
Physical And Chemical

Reactive extraction of levulinic acid using trin-octylamine (TOA) in 1-hexanol was investigated by physical and chemical extractions from aqueous solution at room temperature. Using the equilibrium data, the distribution coefficient (KD), extraction efficiency (E%), loading ratio (Z), stoichiometric loading factor (ZS) and modified separation factor (Sf ) are evaluated. It was observed that chemical extraction provided a better yield than physical extraction. A maximum KD was obtained as 10.715 using 40% TOA (0.9059 mol/L) while 91.46% of the levulinic acid was extracted. By increasing the initial concentration of levulinic acid resulted in a decrease of KD and E%. The KD and E% increased by increasing the TOA concentration from 10 to 40% (0.2264 mol/L to 0.9059 mol/L).

Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

2019 ◽  
Vol 70 (5) ◽  
pp. 1507-1512
Author(s):  
Baker M. Abod ◽  
Ramy Mohamed Jebir Al-Alawy ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Heavy Metal Ions ◽  
Date Palm ◽  
Operating Conditions ◽  
Initial Concentration ◽  
Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

Use of Nanopillars-TiO2 Thin Films in the Photocatalytic Degradation of Bromophenol Blue from Aqueous Solution

2018 ◽  
Vol 6 (1) ◽  
pp. 22-30
Author(s):  
C. Lalhriatpuia ◽  
◽  
Thanhming liana ◽  
K. Vanlaldinpuia
Keyword(s):  
Thin Films ◽  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Bromophenol Blue ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

The photocatalytic activity of Nanopillars-TiO2 thin films was assessed in the degradation of Bromophenol blue (BPB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the XRD, SEM and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data showed anatase phase of TiO2 particles with average particle size of 25.4 and 21.9 nm, for S1 and S2 catalysts respectively. The SEM and AFM images indicated the catalyst composed with Nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The average height of the pillars was found to be 180 and 40 nm respectively for the S1 and S2 catalyst. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of BPB using the UV light was studied at wide range of physico-chemical parametric studies to determine the mechanism of degradation as well as the practical applicability of the technique. The batch reactor operations were conducted at varied pH (pH 4.0 to 10.0), BPB initial concentration (1.0 to 20.0 mg/L) and presence of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of BPB. The maximum percent removal of BPB was observed at pH 6.0 and a low initial concentration of the pollutant highly favours the photocatalytic degradation using thin films. The presence of several interfering ions suppressed the photocatalytic activity of thin films to some extent. The time dependence photocatalytic degradation of BPB was demonstrated with the pseudo-first-order rate kinetics. Study was further extended with total organic carbon measurement using the TOC (Total Organic Carbon) analysis. This demonstrated an apparent mineralization of BPB from aqueous solutions.

A Green and Energy-efficient Photocatalytic Process for accelerated synthesis of Lactic Acid Esters using functionalized quantum dots

2021 ◽  
Author(s):  
Priyanka Verma ◽  
Ravinder Kumar Wanchoo ◽  
Amrit Pal Toor
Keyword(s):  
Quantum Dots ◽  
Lactic Acid ◽  
Low Temperature ◽  
Ambient Temperature ◽  
Energy Efficient ◽  
Photocatalytic Process ◽  
Photochemical Process ◽  
Line P ◽  
Safe Approach ◽  
Acid Esters

Sulphonate-grafted-Titania (SO3H-TiO2) quantum dot catalyzed photochemical process offered an energy-efficient, accelerated, and safe approach to synthesize lactic acid esters at ambient temperature conditions. This low-temperature route is conceived in line...

scholarly journals Preliminary Study on the Use of Ozonation for the Degradation of Dithiocarbamate Residues in the Fruit Drying Process: Mancozeb Residue in Blackcurrant is the Example Used

2013 ◽  
Vol 53 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Piotr Antos ◽  
Anna Kurdziel ◽  
Stanisław Sadło ◽  
Maciej Balawejder
Keyword(s):  
Aqueous Solution ◽  
Ozone Concentration ◽  
Gaseous Phase ◽  
Plant Material ◽  
Water Solution ◽  
Ozone Treatment ◽  
Drying Process ◽  
Initial Concentration ◽  
Preliminary Study ◽  
Treatment Procedures

Abstract In order to reduce the level of dithiocarbamate fungicide mancozeb residues in blackcurrants, two different ozone treatment procedures were evaluated. The first one entailed washing the plant material with an aqueous solution of ozone. This ozone enriched water solution allowed for a 59% reduction of mancozeb residues, compared with the initial concentration. The latter method was based on the utilization of ozone in a gaseous phase combined with a drying process. In that procedure, samples of blackcurrant fruit were exposed to a 19 ppm ozone concentration, and then the blackcurrants were dried. The utilization of ozone in a gaseous phase permitted a 38% reduction of mancozeb residues, in comparison with the initial concentration. As a result of the combination of both processes; ozonation and drying, a 58% reduction of mancozeb residues was achieved.

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