2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Hydroxyapatite and Alizarin sulfonate ARS modeling
interactions for textile dyes removal from wastewaters
W. Lemlikchi, P. Sharrock, M. Fiallo, A. Nzihou and M.-O. Mecherri (*)
Hydroxyapatite (HA) Ca5(PO4)3(OH) is a calcium phosphate usually written
as Ca10(PO4)6(OH)2
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
HA has multiple exchange capacities inside its
structure, including formation of vacancies to
accommodate ions with other valencies, in particular
carbonate ions and alkali and other metal ions.
Hydroxyapatite (HA) is more than an adsorbent and was
previously used for eliminating heavy metals in water pollution
by adsorption and ion exchange.
HA was also used for eliminating textile dyes
from waste waters.
Our previous works showed that HA can be regenerated
after calcination, and reused several times.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Alirarin red sulfonate (ARS) sodium 3-alizarin-sulfonate
(also called Alizarine Carmine, Alizarine Red S, Alizarine S)
is a typical dihydroxyanthraquinone that has been used as a traditional
natural dye originally derived from the roots of plants of the madder genus,
also used a histochemical stain for calcium in bone tissues .
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Textile mordant dyes such as alizarin generally contain
a functional ligand capable of reacting strongly with
Al(III), Cr(III), Co(II), Cu(II), Ni(II), or Fe(II), Fe(III) salts
to give different colored complexes with the textile.
Alizarin could therefore
be used as a
model compound
for more complex dyes.
The adsorption of alizarin red
has long been used to assess
the performance of the apatite
before use in a water treatment facility.
This led us to investigate the way calcium ions interact
simultaneously with ARS and phosphate.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Anthraquinone and Alizarin forms and structures
• Alizarin contains hydroquinone and catechol moiety
(with two adjacent OH phenol groups);
So, according to pH conditions, the
catechol moiety could loose
whether one proton
or two protons
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Assuming pK values (pK (2-OH) = 5.49 and pK(1-OH) = 10.85)
of the diacid alizarin sulfonate given by Wu and Forsling,
we have drawn the theoretical distribution diagram of alizarin
sulfonate (ARS) and that of phosphate system.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Formation of Metal-ARS complexes via two modes:
¤ five-membered complex cycle: so-called
« catecholate » or « diphenolate »;
¤ six-membered complex cycle: so-called
« chelate » or « ketophenolate ».
Translated from: Jana Sanyova, Contribution à l'étude de la structure
et des propriétés des laques de garance, Thèse ULB, Bruxelles 2001.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Many authors like Moriguchi claimed two types of bonding of ARS could be
observed on HA, one involving:
• diphenolate or catecholate salt formation with 2 phenolic hydroxyl groups,
• ketophenolate akin to chelate formation with a phenolic hydroxyl group and
adjacent quinone oxygen
Binding schemes according to Moriguchi et
al., also reported by Ibsen and Birkedal
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The complexation
mechanisms reported in the
literature never involve
participation of
the sulfonate group (-SO3-)
of the alizarin-sulfonate ARS.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Structures of Ca-ARS 1:1 and 1:2 complexes
The doubly deprotonated ARS
forms a 1 to 1 calcium complex.
The monodeprotonated ARS
forms a 1 to 2 complex.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
The ARS dye changes its color with the variation of the pH from
violet (for basic pH) to pink, red, orange and therefore to yellow
(for the most acidic pH values).
A very similar theoretical
spectrum has been given
by Turcanu and Bechtold
for numerous pH values.
Our experimental UV spectrum given for different pH
values after addition of NaOH to 0.1mM ARS solutions.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Our experimental IR spectrum
of HA with increasing
concentrations of ARS
[HA + (5-10-20)% of ARS].
At right: IR spectra of (a) HAP
(microscopic method)
and (b) ARS (KBr method)
T. Moriguchi et al. / Journal of Colloid and Interface Science 260 (2003) 19–25.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
pH jump: corresponds to a difference of pH for a given added volume of
NaOH: HBO2 appears to be stronger in presence of polyols.
pH shifts for
some
concentrations
of alizarin
during its
titration with
NaOH.
The maximum pH
shift occurs at 2
ARS for 1 Ca
pH shift: corresponds to a difference of added volume of NaOH for a given
constant pH value as a function of stoichiometry.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
The maximum pH
shift occurs for
2 ARS for 1 Ca
The 1 to 2 calcium-alizarin complexforms
as follows:
Ca2+ + 2 ARS------ Ca(ARS)2 + 2 H+
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Titration of 1.25 mm calcium
ions in the presence of
increasing ARS concentrations
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
The pH shift is lower than in the
case of Ca + Ars with no
phosphate, but occurs for
2 ARS for 1 PO4
Thus, Alizarin reacts with surface bound
apatite calcium ions
Titration of Ca/P solution with
increasing amounts of alizarin
We had : Ca/PO4= 1.5 = 3:2 => 2 Ca/2PO4=3 ; the maximum shift occurs for
ARS/PO4 = 2 or 2 ARS/PO4 = 4
The complex formulae will be: (ARS)4Ca3(PO4)2.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
pH jumps and
pH shifts
For the mixtures calcium-alizarin, calcium-phosphate and
calcium-phosphate-alizarin, there are both a pH jump and a
pH shift of the equivalent points to the titration of alizarin and
of the phosphorous species originating from apatite HA.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Conclusion:
We tried to show
the interactions of calcium phosphate
with alizarin dye model.
But
much remains to be done
to elucidate the mechanisms of formation
of many other metal-dye complex and especially for
metal-phosphates-dye complexes encountered in
industrial textile mixtures and waste residues.
Pacific berber warrior
double deprotonated
Many thanks
for your attention !
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Addendum:
2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Release of the potential acidity of (weak) boric
acid via exaltation with polyols
Pacific berber warrior
double deprotonated
pH jump during
synergic titration of
boric acid HBO2 0.1
M by NaOH 1M in
presence of
mannitol by the
Sorensen method.
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2nd International Symposium on Innovation and Technology in the Phosphate Industry - [SYMPHOS 2013]
Addendum:
Illustrative example of a synergic titration of copper ions
with alizarin in presence of borates.
Alizarin-borate complex structure as suggested by Panahi et al.