1. Analytical Chemistry
Applications of solvent extraction
Names of participants Ayesha Saleem, Namra Babar,
Amina Ashraf, Ayesha Bibi,
Kainat Sajjad, Wardah Riaz
Roll numbers. 21, 51, 109, 29,37,09
Semester 5th (A)
Instructor Dr. Maria
2. Solvent Extraction
Solvent extraction is a technique which is
used as a mean of sample pre-treatment
or cleanup to separate analyte from matrix
components that would interfere with their
detection or quantitation.
It is also used to pre-concentrate analytes
present in samples at very low levels which
might otherwise be difficult or impossible
to detect or quantify.
3. Extraction in Hydrometallurgy
Used electronic equipment became one of the fastest growing waste streams in the
world. The most of the contemporary research activities on recovery of base and
precious metals from waste PCBs are focused on hydrometallurgical techniques as
more exact, predictable and easily controlled.
Hydrometallurgy is a technique which involves recycling of precious
metals from used electronic equipment through leaching of substance
with acids or bases.
4. Hydrometallurgical process
Leaching
• It involves the use of aqueous solutions to extract metals from metal
bearing material which is brought into contact with a material
containing a valuable metal.
• It involves five basic leaching reactors i.e In-situ, heap, vat, tank and
autoclave
Concentration
• After leaching next is concentration of metal ions that are
to be recovered.
• It involves precipitation, cementation, solvent extraction,
ion exchange.
Recovery of metals
• The final step of hydrometallurgical process. Metals suitable for
sale are often directly produced in the metal recovery step.
• Primary steps of metal recovery processes are electrolysis,
gaseous reduction and precipitation.
5. Solvent Extraction application in nuclear
industry
• Extraction of Uranium and
Plutonium from spent
nuclear fuel.
• Production of radionuclide
Composition of spent fuel
6. PUREX PROCESS (Plutonium and Uranium
refining by extraction)
• Process for the reprocessing of spent nuclear
fuel to separate uranium and plutonium
from the fission products and from one
another. Following the dissolution of the
irradiated fuel in aqueous nitric acid,
uranium and plutonium are transferred to an
organic phase by intensive mixing with an
organic solvent extraction - 30 percent tri-
butyl phosphate (TBP) in kerosene is used as
organic solvent - while the fission products
remain in the aqueous nitric phase. Further
process steps enable the subsequent
separation of uranium and plutonium from
one another.
7. Purex raffinate
The term PUREX raffinate describes the mixture of metals in nitric acid which are left behind
when the uranium and plutonium have been removed by the PUREX process from a nuclear
fuel dissolution liquor. This mixture is often known as high level nuclear waste.
10. Solvent extraction in waste water
treatement
There are several contaminations in waste water playing important role. Many kinds of
organic compounds such as pesticides, herbicides, phenols, PAHC, heterocyclic and
aromatic compounds are included in the waste water.
•Industrial and agriculture production , and people living could be the source of organic
waste water.
•Classic poisonous substances in organic waste water include the following;
Water organic mattter
Formaldehyde
Phenols
Nitrobenzene
PCB’s
PAH’s etc.
Common form of chemical extraction using organic solvent as the extractant
11. Two major extraction techniques for
wastewater treatment
•Solute solvent separation
Reverse osmosis system is the best
example of solute solvent
extraction for treatement of waste
water in various industries.
•Water solvent separation
This type of separation is based on
density gradient technique as the
solvent forms separate layer above the
water because of low density.
•Phenol removal, oily water
desalination etc
12. Extraction in biofuel
• Transesterification:
• For the synthesis of biodiesel, the following materials were used:
oil sample , methanol , and potassium hydroxide (KOH) as a
catalyst. Methanol and potassium hydroxide were pre-mixed to
prepare potassium methoxide, and then added to oil in the
reactor with a mixing speed of 400 rpm for 2 h at 50 °C. The
molar ratio of oil to methanol was 1:10. Finally, the mixture was
left overnight to settle forming two layers, namely: biodiesel
phase (upper layer) and the glycerin-rich phase (lower layer).
Biodiesel extraction methods
Biodiesel as one from important biofuel
types is made from vegetable oils and
animal fats. Biodiesel can be used as a
fuel for vehicles in its pure form, but it is
usually used as a diesel additive to
reduce levels of particulates, carbon
monoxide, and hydrocarbons from
diesel powered vehicles. Biodiesel is
produced from oils or fats using trans
esterification and is the most common
biofuel.
13. Extraction in Biofuel
• Pretreatment is the chemical reaction that converts the complex
polysaccharides to simple sugar. pretreatment of biomass is always
necessary to remove or modify the surrounding matrix of lignin and
hemicellulose prior to the enzymatic hydrolysis of the polysaccharides
(cellulose and hemicellulose) in the biomass. Pretreatment refers to a
process that converts lingo cellulosic biomass from its native form. In
general, pretreatment methods can be classified into three categories,
including physical, chemical, and biological pretreatment. In this step,
biomass structure is broken to fermentable sugars. This project focused on
chemically and biologically pretreatment.
• Fermentation step in which there are a series of chemical or enzymatic
reactions that converted sugar into ethanol. The fermentation reaction is
caused by yeast or bacteria, which feed on the sugar such as
Saccharomyces cerevisae.
• Distillation step in which the pure ethanol is separated from the mixture
using distiller which boil the mixture by heater and evaporate the mixture
to be condensate at the top of the apparatus to produce the ethanol from
joined tube.
Bioethanol extraction
Bioethanol is an alcohol made by
fermentation, mostly from
carbohydrates produced in sugar or
starch crops such as corn or sugarcane.
Cellulosic biomass, derived from non-
food sources such as trees and grasses,
is also being developed as a feedstock
for ethanol production. Ethanol can be
used as a fuel for vehicles in its pure
form, but it is usually used as a
gasoline additive to increase octane
and improve vehicle emissions.
15. Biogas extraction
• Methane fermentation offers an effective means of pollution reduction,
superior to that achieved via conventional aerobic processes. Methane
fermentation is the consequence of a series of metabolic interactions
among various groups of microorganisms. The first group of
microorganisms secretes enzymes which hydrolyze polymeric materials
to monomers such as glucose and amino acids, which are subsequently
converted to higher volatile fatty acids, H2 and acetic acid . In the
second stage, hydrogen-producing bacteria convert the higher volatile
fatty acids e.g., propionic and butyric acids, produced, to H2, CO2, and
acetic acid. Finally, the third group, methanogenic bacteria convert H2,
CO2, and acetate, to CH4 and CO2.
Methane fermentation is a versatile
biotechnology capable of converting
almost all types of polymeric materials to
methane and carbon dioxide under
anaerobic conditions. This is achieved as
a result of the consecutive biochemical
breakdown of polymers to methane and
carbon dioxide in an environment in
which varieties of microorganisms which
include fermentative microbes,
hydrogen-producing, acetate-forming
microbe, and methane-producing
microbes (methanogens) grow and
produce reduced end-products.
Anaerobes play important roles in
establishing a stable environment at
various stages of methane fermentation.
16. Solvent extraction in pharmaceutical and biochemical
• Human insulin-like growth factor (IGF-1)
• Can be separated through solvent
extraction.
• An aqueous two-phase extraction
procedure was used which partitions
soluble non-active (IGF-1) and biomass
solids into separate liquid phases.
Purification of
pharmaceutical
proteins
• Amino acids are constituents of proteins. Not
only amino acids are partitioned by aqueous
two phase system but also proteins can be
separated.
• Production and partitioning of lactic acid can
also done by aqueous two phase system
Partitioning of
amino acids and
oligopeptides
17. Purification of pharmaceuticals from
plants
Ecdosyne and 20-hydroxyacdosyne,hormones both are steroids but
soluble in water.
Their partitioning behavior was manipulated by adding ethanol, sodium
chloride or sodium sulphate to the primary two-phase system.
The recovery of Ecdosyne increased when ethanol was added to the
system.
Partitioning of porphyrin compound can also done by aqueous two-
phase system.
18. Solvent extraction
Ion-Chromatography of Molybdenum isotopes
A procedure was developed that allows precise determination of molybdenum isotope
abundances in natural samples. Purification of molybdenum was first achieved by solvent
extraction using di(2-ethylhexyl) phosphate. Further separation of molybdenum from isobar
nuclides was obtained by ion chromatography using AG1-X8 strongly basic anion exchanger.
Finally, molybdenum isotopic composition was measured using a multiple collector inductively
coupled plasma hexapole mass spectrometer. The abundances of molybdenum isotopes
resulting in an atomic mass of 95.9304. After internal normalization for mass fractionation, no
variation of the molybdenum isotopic composition is observed among terrestrial samples within
a relative precision on the order of 0.00001-0.0001. This demonstrates the reliability of the
method, which can be applied to searching for possible isotopic anomalies and mass fraction.
19. Experiment
• Separation Chemistry:
• The procedure we developed was inspired by the work of Qi-Lu and Mas da,11,12,15 who took
advantage of the affinity of molybdenum for di(2-ethylhexyl)phosphate(C16H35O4P, HDEHP)18 and
used a strongly basic anion exchanger (AG1-X8, 100-200 mesh, chloride form)19 in order to achieve
fine separation of molybdenum from potential interfering species.
• After digestion of the samples in a suitable medium,20 the solution was evaporated to dryness and
taken up in 5 mL of perchloric acid(HClO4), 4 M.
• The solution was poured into a 10-mL polypropylene centrifuge tube where it was equilibrated with 5
mL of tube where it was equilibrated with 5 mL of HDEHP diluted to 0.72 M with cyclohexane (C6H12).
• During this step, the molybdenum was strongly partitioned into the organic phase, while most matrix
elements remained in the aqueous phase. The
supernatant was hand-pipetted and washed three times with 5 mL HClO4, 4 M, and two times with 5
mL nitric acid (HNO3), 10 M. Next, molybdenum was back-extracted from the organic phase by two
equilibrations with 5 mL HNO3/hydrogen peroxide (H2O2),
10 M/1 M.
20. Experiment
• The back extractant was transferred into a 15-mL Teflon PFA vessel.
• The solution was doped with 2 mL of H2O2, 9.9 M, and baked overnight at 400 K in
order to ensure oxidation and subsequent loss of ruthenium and trace organic phases.
The back extractant was evaporated to dryness and taken up in 1 mL of hydrofluoric acid
(HF)/hydrochloric acid (HCl), 1 M/0.5 M, which was then loaded onto a Bio-Rad Poly-Prep
column filled with 0.6 mL of AG1-X8, 200-400 mesh, chloride-form resin previously
washed and conditioned with 5 mL of H2O; 5 mL of HCl, 6 M; 5 mL of H2O; 5 mL of HCl,
1 M; 5 mL of H2O; and finally, 5 mL of HF/HCl, 1 M/0.5 M.
• Matrix elements were removed using 6 mL of HF/HCl 1 M/0.5 M. Zirconium was eluted
with 4 mL of HCl, 6 M. Finally, molybdenum was stripped from the column using 6 mL of
HCl, 1 M. The ion exchange step was repeated twice. Molybdenum was then ready for
mass spectrometric analysis.
21. Conclusion
• Solvent extraction of molybdenum allows large quantities of sample to be treated. Ion exchange
chromatography makes itpossible to separate molybdenum completely from interfering species.
• The recent advent of MC-ICP-Hex-MS offers high sensitivity and efficient correction of isobaric
interferences.
• These advances permit natural molybdenum isotope variations to be investigated with
unprecedented precision.
• Important subjects such as inheritance of molybdenum nucleosynthetic anomalies in the solar
system, isotope mass fractionation by use of the multiple spike technique, electron capture of the
possible extinct radionuclide 97Tc to form 97Mo, production of molybdenum isotopes from fission,
anomalous isotope effects, double â decay of 96Zr to form 96Mo, and molybdenum isotope
variations resulting from cosmic ray exposure in space can be dressed confidently with this method
