CSMCRI
21st Mid-year Meeting of the Indian Academy of Sciences
Faculty Hall, IISc Bangalore
July 2, 2010
Case Studies of Recent Innovations in the
Area of Salt and Marine Chemicals
Pushpito K. Ghosh
Central Salt & Marine Chemicals Research Institute (CSMCRI),
G. B. Marg, Bhavnagar 364002, Gujarat
www.csmcri.org
CSMCRI
CSMCRI
Marine Biotechnology
& Ecology
Solar
Applications
Corrosion
Salinity
Sea
Water
Wasteland
research
Solar
Evapo-
Salt & Marine
Chemicals
ration
Catalysis
Desalination &
Membrane
Technology
The CSIR
Family
Specialty
Materials &
Fertilizers
Coordination
Chemistry
Source: Ullmann’s
Encyclopaedia
CSMCRI
Improvement in
industrial grade
salt quality has a
profound impact
downstream.
The recovery of common salt & marine chemicals from
seawater is based on fractional crystallization
Sea Brine
3-3.5o Be
Conversion factor : Sp.gr. = 145/(145 – 0Be’)
Magnesium
Chloride
Recovery
CaCO3
Crystallization
Gypsum
Crystallization
6-10o Be’
12-240Be’
Pre
Crystallizing
area
24-25o Be’
Salt
Storage
Kainite Type
Mixed Salt
Salt
35 - 37.5oBe’
Bromine
Recovery &
Separation of
Crude Salt
29 – 35 0 Be’
Bittern
Reservoir
Reservoir
Condensers
Crystallizer
25 - 29o Be’
CSMCRI
Recognising that desulphatation of brine holds the key to pure salt and KCl
and using the effluent of soda ash industry to make this happen economically
Distiller Waste
Solar Evaporation
Sea Brine
Desulphated
Bittern
Desulphated
Brine
Evaporation
High Purity NaCl
Gypsum
Constituents
Salt through
Traditional
Process (%)
Salt from
Desulphated
Brine (%)
Ca
0.3 – 0.4
0.07
Mg
0.1 – 0.12
0.03
SO4
0.80 – 1.00
0.09
Source: sub-soil brine
Naturally formulated low sodium
salt will reach people globally
through Unilever Food Products
Carnallite
KCl.MgCl2.3H2O
Solvay Process
CaCO3+ CaO+CO2
NaCl/ KCl
CaO+H2O  Ca(OH)2
(low sodium salt)
NH3+H2O  NH4OH
NaCl+NH4OH +CO2  NH4Cl+NaHCO3
2NaHCO3  CO2+H2O+Na2CO3
2NH4Cl+Ca(OH)2  2NH3+2H2O+CaCl2
Immediate beneficiaries would be soda ash
industries who are backward integrated to salt
production.
US patent Nos. 6,776,972 (2004);
6,890,509 (2005)
CSMCRI
Making solar salt quality less sensitive to brine composition
CSMCRI
28
28
26
26
24
22
22
20
20
%T
%T
24
18
16
18
16
14
14
12
12
10
10
8
500
Solar salt of exceptional purity – never before
achieved in the field – was obtained through an
inexpensive process of brine clarification (for
nucleation control) and pH adjustment (to prevent
agglomeration as a result of magnesium oxychloride
formation).
Brine
1000
1500
2000
cm
2500
-1
3000
3500
500
1000
1500
2000
cm
2500
3000
3500
-1
Peak at 668 cm-1 (FT-IR) indicative of
impurities of magnesium oxy compounds are
much reduced through the invention.
Constituents (%w/w)
Ca2+
Mg2+
SO42-
I(ppb)
NaCl
Normal
0.16
0.27
0.60
>800
>98.5
Clarificati
on & pH
control
0.07
0.04
0.18
<150
> 99.3
EP1928569; US Pat appln No. 11/992533 dtd: 25/03/2008
US Pat appln No. 12/240762 dtd: 29/09/2008
Technology demonstration at 10,000 tons scale
for Grasim Ltd. in Navlakhi, Gujarat
Near spherical (Rhombic Dodecahedron) Common Salt : The idea was
to enhance free flow property (CSMCRI-HUL collaboration)
CSMCRI
THE 6th ANNUAL YEAR IN IDEAS; Salt
That Doesn't Stick
By CLIVE THOMPSON
Published: December 10, 2006
Key Inventions
• Suitable for production in solar pans
• Recycling of glycine (habit modifier)
without affecting salt morphology
US Patent No: 7,220,435 dated 22 May 2007
Cryst. Growth & Des., 2006, 6, 1591-1594
We have now made round salt without any chemical
additives.
a
b
c
Indian Patent Application
0060/Del/2008;
PCT/IN08/00568
“We wish to thank you for
your ability to provide us
with exactly what we had
been searching for and
expecting to find.”
500 µm
d
600 µm
500 µm
f
e
Allergan Medical, USA
800 µm
1000 µm
1200 µm
Cubic and Spherical salt from different brines
Cryst. Growth & Design (submitted)
a
The flowability of round salt is superior
to that of the commercially available
branded salt P1010103 salt flow.mpg
500 µm
300 m
CSMCRI
The Invention of Vegetable Salt
CSMCRI
CSMCRI has successfully developed a
process of densification of the natural habitat
(left inset) of Salicornia brachiata and over
100 hectare of such densification has been
undertaken since 2005. Growing popularity of
vegetable salt could spur large scale demand
for Salicornia.
US Patents 6,929,809 and 7,208,189
Key Inspiration: To make cultivation
of Salicornia on saline wastelands
more viable by utilising the waste
biomass after removal of seeds.
“Green Bromine”: A New Concept in Ecofriendly Bromination
Bromination with "Green Bromine"
Eco-friendly
Versatile
Atom Efficient
Cost-effective
Salt bittern
pH 2-3
Green
Bromine
4NaBr + 2NaBrO3 + 6NaCl
Cl2
NaOH + Cl2
5:1 Br/BrO3 (BR-A) (addition)
2:1 Br/BrO3 (BR-S) (substitution)
6RH
+
Aq. NaCl
6H
5NaBr +NaBrO3
(Bromine precursor)
6RBr
Debrominated
bittern
CSMCRI
Br2
(Transient
formation)
1:8 Br/BrO3 (BR-O) (oxidation)
H+
3 Br2
Aq. NaOH
Liquid
Bromine
Collaborations with Professor B.
C. Ranu and Dr. D. Basavaiah
are gratefully acknowledged.
US Patent No: 6,740,253 dated 25 May 2004.
Green Chem. 2006, 8, 916-922 ; Green Chem. 2008, 10, 232-237 ; J. Org. Chem. 2009, 74, 7947-7950;
Ind. Eng. Chem. Res. 2010, 49, 1236–1241
Atom efficient syntheses of useful organic
compounds with green bromine
CSMCRI
Green bromine-related technologies have been licensed
to two companies. A number of process patents have
been granted.
PROJECT PROGRESS
Archean’s potash project
CSMCRI
gets first-stage
environment nod
The Ministry of Environment and Forest has specified
terms of reference for environment impact
assessment (EIA) for Archean Chemical Industries P.
Ltd’s (ACIPL’s) potassium sulphate fertiliser plant to
be located in Kachchh region of Gujarat. The project
envisages manufacture of 100,000 tonnes per annum
(tpa) of sulphate of potash, 12,500-tpa of liquid
bromine, 2,500-tpa of green bromine,...... .
Chemical Weekly June 22, 2010
“The project concept of CSMCRI remains unchanged.
We are investing based on the conditions in the
market, project execution plan and a phased
program.”
C. G. Sethuram, Archean (March 25, 2010)
SOP (K2SO4) offers an advantage over MOP (KCl) currently
used by farmers with special focus on the following:
• Chloride sensitive crops
• Dryland agriculture
• Sulphur responsive crops
• Drip irrigation
• Areas deficient in K & S
Product strategy was also
guided by the compositional
advantage of sea bittern in so
far as SOP production is
concerned.
CSMCRI
Making SOP Production Viable through Co-production of MgO
KAINITE TYPE
MIXED SALT
KCl.MgSO4.3H2O
US Patent 7,041,268 (2006)
Ind. Eng. Chem. Res. 2006, 45, 1551-1556
WATER
KCl SOLUTION
CF
DECOMPOSER
SCHOENITE
REACTOR
CF
SOP
SCHOENITE
END LIQUOR
CSMCRI
SOP END - LIQUOR
CaO
REACTOR
Filtration
Mg(OH)2
CaCl2
Crude MOP
Salt Pan
Salt Pan
Refining
CaSO4
Key Innovations:
MgO
• Lime and bittern are the only raw material inputs
• All operations under ambient conditions
• Avoids froth floatation
• Generates required KCl for SOP as part of the process
NaCl
CSMCRI
Ultrapure MgO
suitable for LD
converter for primary
steel making and Mg
production
RUL > 1680oC
“The undersigned and Dr. Haldar had developed the magnesite refractory from your
magnesia. The refractory properties along with the photographs of the samples
after the test is given in the attached file. The 99% MgO grade gave excellent
results. “11 May 2010
(Dr. Arup Ghosh, Scientist F, Refractories Division
Central Glass and Ceramic Research Institute)
“We have analysed the MgO sample (99% pure sample was sent) of CSMCRI and
found it suitable for Mg production.”
Swatantra Prakash, Sct G and Head Metal Extraction and Forming Division, National
Metallurgical Laboratory, Jamshedpur
Potash can be recovered through selective extraction from bittern instead
of through fractional crystallization. This would help conserve land
requirement.
NO 2
H
O2N
N
O 2N
NO2
NO2 O2N
Dipicrylamine (DPA)
Ca(OH) 2
CaSO 4
Ca 2 +(DPA ) 2
(sol.)
DPA
+
CaSO 4
Bittern
+
+
( Na+, K , Mg 2 ,
2Ca2+, SO4 )
K Cl
HCl
CSMCRI
K + (DPA )
+
CaSO 4
(ppt.)
+
K -f ree bittern
Ion chromatogram of sea bittern
(top) and the precipitate separated
from bittern with DPA- .
PCT/IN2005/000441
Eur. J. Inorg. Chem. 2005, 2198-2205
Macro- and micronutrients in Kappaphycus sap
g/L
mg/L
Protein
0.85
Phosphorous 29.6
Fat
0.024
Iron
85.8
Carbohydrate 18.00
Manganese
2.2
Sodium
0.18
Nickel
3.5
Potassium 3.58
Copper
0.78
Magnesium 1.17
Zinc
4.74
Calcium
0.33
Iodine
1.60
Data courtesy: National Institute of Nutrition,
Hyderabad,
US Patent No. 6,893,479; EP 1534757 (to CSIR)
J. Agric. Food Chem. 2010, 58, 4594–4601
17
CSMCRI
Kappaphycus
alvarezii cultivation may offer a
potential opportunity to recover potash by biological
means besides the direct use of the sap as a potent
foliar spray and biomass as source of energy.
Conclusions
CSMCRI
The presentation attempted to illustrate case studies
of inventions in the seemingly mature areas of salt &
marine chemicals.
These inventions originated from genuine needs,
street smart thinking, systems integration and
application of basic chemistry.
Acknowledgement
• All those who have contributed to the work
• Funding agencies
• Collaborators and licensees
• CSIR
Thank you