Title of Invention	A NOVEL PROCESS FOR CONCENTRATION OF POLYMETALLIC MANGANESE SEA NODULES FOR EXTRACTION OF VALUABLE METALS LIKE NICKEL, COPPER, COBALT AND MANGANESE
Abstract	A novel process for concentration of polymetallic manganese sea nodules for exraction of valuable metals like copper, nickel, cobalt and manganese which comprises; i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS size, ii) pressure leaching the said ground polymetallic manganese sea nodules in caustic solution of strength in the range of 30 - 50% at a temperature 200 - 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant agitation, iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali and entrapped soluble salts, v) drying the polymetallic magnaese sea nodules concentrate, extracting the valuable metals from the said concentrate by known methods

Title of Invention

A NOVEL PROCESS FOR CONCENTRATION OF POLYMETALLIC MANGANESE SEA NODULES FOR EXTRACTION OF VALUABLE METALS LIKE NICKEL, COPPER, COBALT AND MANGANESE

Abstract

A novel process for concentration of polymetallic manganese sea nodules for exraction of valuable metals like copper, nickel, cobalt and manganese which comprises; i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS size, ii) pressure leaching the said ground polymetallic manganese sea nodules in caustic solution of strength in the range of 30 - 50% at a temperature 200 - 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant agitation, iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali and entrapped soluble salts, v) drying the polymetallic magnaese sea nodules concentrate, extracting the valuable metals from the said concentrate by known methods

Full Text	The present invention relates to a novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like nickel, copper, cobalt and manganese. Ocean nodules represent one of the world's largest untapped deposits of non-ferrous metals. Nickel, copper, cobalt and manganese are present in enormous quantities, enough to supply hundreds of years of demand at current consumption levels. Nevertheless, the sea nodules cannot be expected to displace current landbased metal resources until competitive methods for mining and processing of sea nodules are developed. In the case of processing the manganese sea nodules, the problem is that the nodule matrix is a mixture of iron and manganese oxyhydroxides which cannot be easily beneficiated in contrast to sulfide minerals. Therefore, it is necessary to develop a suitable process to concentrate the sea nodules so that the concentrate produced can be treated by several conventional routes including hydrometallurgical and pyrometallurgical techniques to extract the valuable metals like nickel, copper, cobalt and manganese. In the hitherto known dry process (D.W.Fuerstenau and K.N.Han, Department of material science and mineral engineering laboratories at U.C, Berkeley. Mineral processing and Techknolgy Review 1983, voLlpp 1-83) which uses high-intensity magnetic separation technique to concentrate the ground sea nodules. In another hitherto known segregation process (M.Hoover, K,N.Han and D.W. Fuerstenau, International Journal of Mineral Processing 2(1975) 173-185) which involves roasting the ground sea nodules with a reducing agent and halide salt at 850°C and subsequent recovery of metal values by screaning, leaching or flotation operation (Edser E and Taplin, B 1925. Improvements in or relating to the heat treatment and concentration of ores. Brit ish Patent, 264-584). Yet another known process (R.Sridhar, Thermal upgrading of sea nodules, Journal of metals, December (1974) p.p 18-22) where briquetted ground nodules with reductant was heat treated between 1100-1215°C under reducing atmosphere. After heat treatment, the samples were ground and magnetically separated in a Davis tube at 4800 gauss. In the hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules(A. K. Saha£. H. Khan and D. D. Akerkar patent No 1285/Del/90) where rediuction of sea nodules was carried out with hgh volatile non-coking coal as reductant. The reduced sea nodule was subsequently leached in ammonia/ammoniun carbonate sluitionwhere valuable metals like nickel copper cobalt were gone in solution leaving iron and manganese in the residue. Another hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules (A. K. Saha, Z. H. Khan and D. D. Akerkar patent No ll82/Del/90. An improved process for extraction of nickel, copper and cobalt from manganese sea nodules using lignite as reductant) where nickel, copper and cobalt are reduced to metallic phase and subsequenth/ metallic values are leached out in ammonia/ ammonium carbonate solution. Yet another hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules (R. K. Jana & D. D. Akerkar patent No 954/del/88.An improved process for reductive leaching for porymetallie sea nodules for the recovery of nickel, copper and cobalt where metallic values are directly leached in ammoniacal medium under reduced atmosphere. The hitherto known process have the following draw backs: In the physical beneficiatkm process the recovery of valuable metals like nickel, copper, cobalt, manganese is not more than 60% and implimentation of such processing techniques in practice is very doubtful. In the segregation process the recovery of valuable metals does not go beyond 75%. Heat energy consumption is more. Moreover, presence of chloride ion during roasting corrodes the processing equipment. In the thermal upgrading process the energy consumption is high, and the number of unit operation is more. The high cost of the process defeats the commercial application. Moreover manganese recovery is very poor (31.1%) although the recovery of nickel, copper and cobalt is around 90%. Therefore, R&D efforts have been made to develop an economic and viable process to concentrate the porymetallic manganese sea nodules so that the upgraded sea nodules can be treated by several routes including hydrometallurgieal and pyrometallurgical techniques for extraction of valuable metals like nickel, copper, cobalt and manganese. The main object of the present invention is to provide a novel process for concentration of porymetallic manganese sea nodules for extraction of valuable metals, like nickel, copper, cobalt and manganese. Another object of the present invention is to provide a novel process for concentration of Polymetallic manganese sea nodules whereby upgraded concentrate is produced without loss of valuable metals. Still another object of the present invention is to provide a novel process for concentration of polymetallic manganese sea nodules whereby costly chemicals such as caustic soda is recovered and recycled and thereby reducing the cost of production. In the process of present invention, the polymetallic manganese sea nodules containing gangue materials like silica, alumina etc, are subjected to pressure leaching in caustic solution under temperature where silica, alumina etc, present in the polymetallic manganese sea nodules are chemically reacted with caustic solution producing water soluble salts, leaving the unreacted metal values like nickel, copper, cobalt, manganese etc, in the resudye (concentrate). The chemical reactions occurring during caustic leaching may represent as follows: Si02 + 2NaOH = Na2 Si03 + 2H20 (1) AI203 + 2NaOH = 2NaAI02+H20 (2) After leaching, solid/liquid separation is done by filtration. The concentrate containing valuable metals is repeatedly washed with water to free it from alkali and entraped soluble salts. The concentrate containing valuable metals like nickel, copper, cobalt, manganese etc, thus produced can be used for extraction of nickel, copper, cobalt and manganese by conventional pyrometallurigical or hydrometallurgical methods. After alkali leaching, the filtrate is further processed for purification and recovery of caustic solution by conventional process. The recovered caustic solution can be recycled. Accordingly, the present invention provides a novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like copper, nickel, cobalt and manganese which comprises; i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS size, ii) pressure leaching the said ground polymetallic manganese sea nodules in caustic salt solution of strength in the range of 30 - 50% at a temperature 200 - 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant agitation, iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali entraped soluble salts, (v) drying the pohlymetallic manganese sea nodules concentrate, (vi) extracting the valuable metals from the said concentrate by known methods According to a feature of this invention, the ground polymetallic manganese sea nodules employed may be selected from the polymetallic manganese sea nodules having the following range: (Table Removed) According to another feature of this invention the caustic salts used are such as caustic soda, caustic potash and may be of commercial grade. According to yet another feature of this invention the pulp density of the slurry may vary from 1.30 to l.60 gm/cc. According to still another feature of this invention leaching time may vary from 4-6 hours. According to yet another feature of this invention the polymetallic manganese sea nodule concentrate produced may be dried at a temperature in the range of 100 to 120°C for a period of 4 to 6 hours. According to further feature of this invention, the leach-liquor produced on pressure leaching contains free caustic hydroxide and soluble silicate of alkali metal which on further processing by conventional process produce pure caustic hydroxide solution to be used for recycling. By the process of present invention most of gangue materials are removed and concentrate of porymetallic manganese sea nodules with 60% yield with minor loss of metallic values like nickel, copper, cobalt, manganese etc. is produced which is suitable for extraction of nickel, copper, cobalt and manganese by conventional routes. The novelty of the present invention is the pressure leaching of the porymetallic sea nodules in alkali solution like caustic soda, caustic potash thereby upgrading the nickel from0.91 to 1.5 %, copper from 0.81 to 1.35 % and cobalt from 0.09 to 0.15%. The upgraded concentrate can recover over 99% nickel ,copper and copper 85 % iron and 75 % manganese. The following examples are given by way of illustration of the present invention and therefore should not be construed to the limit the scope of the present investigation. The ground porymetallic manganese sea nodules treated were of the following composition: (Table Removed) Example-1 50 gms. of ground polymetallic manganese sea nodules sample was leached under conditions of agitation(100 strokes per minute), oxygen pressure(70 kg per sq.cm), pulp density(1.5 gm per cc) and same solution strength(40%) of causting soda at varied temperature in the range of 240 to 280°C for 4 hours. After leaching solid/liquid separation was done by filtration followed by washing with water. The solid concentrate was then dried at 110°C for 6 hours. The resuls of the concentrate produced are given in Table-1. Table-l (Table Removed) Example-2 50 gms. of ground polymetallic manganese sea nodules sample were subjected to pressure leaching with different concentration of NaOH solution at 270°C for 5 hours under oxygen pressure(70 kg per sq.cm). The solid/liquid ratio are invariably meintained 1:10 under continuous agitation. The solid/liquid separation was done by filtration followed by washing with water. The concentrate was dried at 110°C for 6 hours. The results are given in table-2 Table-2 (Table Removed) Example-3 50 grams of sea nodule sample was subjected to pressure leaching in 40 % strength of NaOH solution at 240°-C for 5 hours.The leaching was carried out under different oxygen pressure under identical conditions of agitation(100 strokes per minute) and solid :liquid ratio 1:10. The results are given in table-3 Table-3 (Table Removed) Example-4 50 grams of ground poly metallic sea nodules ground sample was subjected alkali pressure leaching at 250C under 70 kg per sq.cm of oxygen pressure for different times. The strength of caustic solution was maintained at 40 % NaOH. The slurry was then filtered and the concentrate was thoroughly washed with water. The results are given in table-4 Table-4 (Table Removed) Example-5 50 grams of manganese nodules was subjected to in 40% NaOH solution with different pulp density under identical condition of temperature(2700C) pressure(70 kg per sq.cm) for 4 hours. The slurry after leaching was filtered and the residue(concentrate) was dried at 110°C for 6 nours.The results are given in table-5 Table-5 (Table Removed) The main advantages of the present invention are: 1) In the novel process of present invention the recovery of nickel, copper and cobalt in the concentrate produced are of the order of 99% where as in the existing processes recovery of these metals are of the order 75% 2) In the present invention the recovery of iron in the concentrate produced is more than 85% where as in the existing processes iron recovery is less than 65%. 3) hi the present invention recovery of manganese is more than 75% where as in the existing processes manganese recovery is only 35%. 4) hi the present invention consumption of heat energy is much less when compared to the existing processes. 5) In the present invention, caustic solution is recycled leading to less processing cost. We Claim: 1. A novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like copper, nickel, cobalt and manganese which comprises; i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS size, ii) pressure leaching the said ground polymetallic manganese sea nodules in caustic salt solution of strength in the range of 30 - 50% at a temperature 200 - 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant agitation, iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali and entrapped soluble salts, v) drying the polymetallic magnaese sea nodules concentrate, vi) extracting the valuable metals from the said concentrate by known methods. 2. A novel process as claimed in claims 1 and 2 wherein caustic salt used is selected from caustic soda, caustic potash of commercial grade. 3. A novel process as claimed in claims 1 to 3 wherein leaching is done with pulp density in the range of 1.30 to 1.60 gm/cc. 4. A novel process as claimed in claims 1 to 4 wherein leaching is done for a period of 4-6 hours. 5. A novel process as claimed in claims 1 to 5 wherein polymetallic manganese sea nodule concentrate is dried at a temperature in the range of 110 to 120°C for 4 to 6 hours. 6. A novel process as claimed in claims 1 to 6 wherein caustic solution is recovered from leach liquors by conventional methods and after purification is recycled. 7. A novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like nickel, copper, cobalt and manganese substantially as herein described with reference to examples.

Full Text

The present invention relates to a novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like nickel, copper, cobalt and manganese.
Ocean nodules represent one of the world's largest untapped deposits of non-ferrous metals. Nickel, copper, cobalt and manganese are present in enormous quantities, enough to supply hundreds of years of demand at current consumption levels. Nevertheless, the sea nodules cannot be expected to displace current landbased metal resources until competitive methods for mining and processing of sea nodules are developed. In the case of processing the manganese sea nodules, the problem is that the nodule matrix is a mixture of iron and manganese oxyhydroxides which cannot be easily beneficiated in contrast to sulfide minerals. Therefore, it is necessary to develop a suitable process to concentrate the sea nodules so that the concentrate produced can be treated by several conventional routes including hydrometallurgical and pyrometallurgical techniques to extract the valuable metals like nickel, copper, cobalt and manganese.
In the hitherto known dry process (D.W.Fuerstenau and K.N.Han, Department of material science and mineral engineering laboratories at U.C, Berkeley. Mineral processing and Techknolgy Review 1983, voLlpp 1-83) which uses high-intensity magnetic separation technique to concentrate the ground sea nodules.
In another hitherto known segregation process (M.Hoover, K,N.Han and D.W. Fuerstenau, International Journal of Mineral Processing 2(1975) 173-185) which involves roasting the ground sea nodules with a reducing agent and halide salt at 850°C and subsequent recovery of metal values by screaning, leaching or flotation operation (Edser E and Taplin, B 1925. Improvements in or relating to the heat treatment and concentration of ores. Brit ish Patent, 264-584).
Yet another known process (R.Sridhar, Thermal upgrading of sea nodules, Journal of metals, December (1974) p.p 18-22) where briquetted ground nodules with reductant was heat treated between 1100-1215°C under reducing atmosphere. After heat treatment, the samples were ground and magnetically separated in a Davis tube at 4800 gauss.
In the hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules(A. K. Saha£. H. Khan and D. D. Akerkar patent No 1285/Del/90) where rediuction of sea nodules was carried out with hgh volatile non-coking coal as reductant. The reduced sea nodule was subsequently leached in ammonia/ammoniun carbonate sluitionwhere valuable metals like nickel copper cobalt
were gone in solution leaving iron and manganese in the residue.
Another hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules (A. K. Saha, Z. H. Khan and D. D. Akerkar patent No ll82/Del/90. An improved process for extraction of nickel, copper and cobalt from manganese sea nodules using lignite as reductant) where nickel, copper and cobalt are reduced to metallic phase and subsequenth/ metallic values are leached out in ammonia/ ammonium carbonate solution.
Yet another hitherto known process for extaction of Ni, Cu and Co from manganese sea nodules (R. K. Jana & D. D. Akerkar patent No 954/del/88.An improved process for reductive leaching for porymetallie sea nodules for the recovery of nickel, copper and cobalt where metallic values are directly leached in ammoniacal medium under reduced atmosphere.
The hitherto known process have the following draw backs:
In the physical beneficiatkm process the recovery of valuable metals like nickel, copper, cobalt, manganese is not more than 60% and implimentation of such processing techniques in practice is very doubtful.
In the segregation process the recovery of valuable metals does not go beyond 75%. Heat energy consumption is more. Moreover, presence of chloride ion during roasting corrodes the processing equipment.
In the thermal upgrading process the energy consumption is high, and the number of unit operation is more. The high cost of the process defeats the commercial application. Moreover manganese recovery is very poor (31.1%) although the recovery of nickel, copper and cobalt is around 90%.
Therefore, R&D efforts have been made to develop an economic and viable process to concentrate the porymetallic manganese sea nodules so that the upgraded sea nodules can be treated by several routes including hydrometallurgieal and pyrometallurgical techniques for extraction of valuable metals like nickel, copper, cobalt and manganese.
The main object of the present invention is to provide a novel process for concentration of porymetallic manganese sea nodules for extraction of valuable metals, like nickel, copper, cobalt and manganese.
Another object of the present invention is to provide a novel process for concentration of
Polymetallic manganese sea nodules whereby upgraded concentrate is produced without loss of valuable metals.
Still another object of the present invention is to provide a novel process for concentration of polymetallic manganese sea nodules whereby costly chemicals such as caustic soda is recovered and recycled and thereby reducing the cost of production.
In the process of present invention, the polymetallic manganese sea nodules containing gangue materials like silica, alumina etc, are subjected to pressure leaching in caustic solution under temperature where silica, alumina etc, present in the polymetallic manganese sea nodules are chemically reacted with caustic solution producing water soluble salts, leaving the unreacted metal values like nickel, copper, cobalt, manganese etc, in the resudye (concentrate). The chemical reactions occurring during caustic leaching may represent as follows:
Si02 + 2NaOH = Na2 Si03 + 2H20 (1)
AI203 + 2NaOH = 2NaAI02+H20 (2)
After leaching, solid/liquid separation is done by filtration. The concentrate containing valuable metals is repeatedly washed with water to free it from alkali and entraped soluble salts. The concentrate containing valuable metals like nickel, copper, cobalt, manganese etc, thus produced can be used for extraction of nickel, copper, cobalt and manganese by conventional pyrometallurigical or hydrometallurgical methods.
After alkali leaching, the filtrate is further processed for purification and recovery of caustic solution by conventional process. The recovered caustic solution can be recycled.
Accordingly, the present invention provides a novel process for concentration of polymetallic manganese sea nodules for extraction of valuable metals like copper, nickel, cobalt and manganese which comprises;
i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS size, ii) pressure leaching the said ground polymetallic manganese sea nodules in caustic salt solution of strength in the range of 30 - 50% at a temperature 200 - 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant agitation, iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali
entraped soluble salts,
(v) drying the pohlymetallic manganese sea nodules concentrate, (vi) extracting the valuable metals from the said concentrate by known methods
According to a feature of this invention, the ground polymetallic manganese sea nodules employed may be selected from the polymetallic manganese sea nodules having the following range:

(Table Removed)
According to another feature of this invention the caustic salts used are such as caustic soda, caustic potash and may be of commercial grade.
According to yet another feature of this invention the pulp density of the slurry may vary from 1.30 to l.60 gm/cc.
According to still another feature of this invention leaching time may vary from 4-6 hours.
According to yet another feature of this invention the polymetallic manganese sea nodule concentrate produced may be dried at a temperature in the range of 100 to 120°C for a period of 4 to 6 hours.
According to further feature of this invention, the leach-liquor produced on pressure leaching contains free caustic hydroxide and soluble silicate of alkali metal which on further processing by
conventional process produce pure caustic hydroxide solution to be used for recycling.
By the process of present invention most of gangue materials are removed and concentrate of porymetallic manganese sea nodules with 60% yield with minor loss of metallic values like nickel, copper, cobalt, manganese etc. is produced which is suitable for extraction of nickel, copper, cobalt and manganese by conventional routes.
The novelty of the present invention is the pressure leaching of the porymetallic sea nodules in alkali solution like caustic soda, caustic potash thereby upgrading the nickel from0.91 to 1.5 %, copper from 0.81 to 1.35 % and cobalt from 0.09 to 0.15%. The upgraded concentrate can recover over 99% nickel ,copper and copper 85 % iron and 75 % manganese.
The following examples are given by way of illustration of the present invention and therefore should not be construed to the limit the scope of the present investigation.
The ground porymetallic manganese sea nodules treated were of the following composition:
(Table Removed)
Example-1
50 gms. of ground polymetallic manganese sea nodules sample was leached under conditions of agitation(100 strokes per minute), oxygen pressure(70 kg per sq.cm), pulp density(1.5 gm per cc) and same solution strength(40%) of causting soda at varied temperature in the range of 240 to 280°C for 4 hours. After leaching solid/liquid separation was done by filtration followed by washing with water. The solid concentrate was then dried at 110°C for 6 hours. The resuls of the concentrate produced are given in Table-1.
Table-l
(Table Removed)
Example-2
50 gms. of ground polymetallic manganese sea nodules sample were subjected to pressure leaching with different concentration of NaOH solution at 270°C for 5 hours under oxygen pressure(70 kg per sq.cm). The solid/liquid ratio are invariably meintained 1:10 under continuous agitation. The solid/liquid separation was done by filtration followed by washing with water. The concentrate was dried at 110°C for
6 hours. The results are given in table-2
Table-2
(Table Removed)

Example-3
50 grams of sea nodule sample was subjected to pressure leaching in 40 % strength of NaOH solution at 240°-C for 5 hours.The leaching was carried out under different oxygen pressure under identical conditions of agitation(100 strokes per minute) and solid :liquid ratio 1:10. The results are given in table-3
Table-3
(Table Removed)
Example-4
50 grams of ground poly metallic sea nodules ground sample was subjected alkali pressure leaching at 250C under 70 kg per sq.cm of oxygen pressure for different times. The strength of caustic solution was maintained at 40 % NaOH. The slurry was then filtered and the concentrate was thoroughly washed with water. The results are given in table-4
Table-4
(Table Removed)
Example-5
50 grams of manganese nodules was subjected to in 40% NaOH solution with different pulp density under identical condition of temperature(2700C) pressure(70 kg per sq.cm) for 4 hours. The slurry after leaching was filtered and the residue(concentrate) was dried at 110°C for 6 nours.The results are given in table-5
Table-5
(Table Removed)

The main advantages of the present invention are:
1) In the novel process of present invention the recovery of nickel, copper and cobalt in the
concentrate produced are of the order of 99% where as in the existing processes recovery of these
metals are of the order 75%
2) In the present invention the recovery of iron in the concentrate produced is more than 85% where
as in the existing processes iron recovery is less than 65%.
3) hi the present invention recovery of manganese is more than 75% where as in the existing
processes manganese recovery is only 35%.
4) hi the present invention consumption of heat energy is much less when compared to the existing
processes.
5) In the present invention, caustic solution is recycled leading to less processing cost.

We Claim:
1. A novel process for concentration of polymetallic manganese sea nodules for
extraction of valuable metals like copper, nickel, cobalt and manganese which
comprises;
i) crushing and grinding polymetallic manganese sea nodules to - 100 mesh BSS
size, ii) pressure leaching the said ground polymetallic manganese sea nodules in
caustic salt solution of strength in the range of 30 - 50% at a temperature 200
- 280°C in presence of oxygen at a pressure 40 - 90 kg/sq cm under instant
agitation,
iii) filtering the slurry so obtained in step (ii) for solid/liquid separation, iv) washing the filtered solid obtained from step (iii) with water to remove alkali
and entrapped soluble salts,
v) drying the polymetallic magnaese sea nodules concentrate, vi) extracting the valuable metals from the said concentrate by known methods.
2. A novel process as claimed in claims 1 and 2 wherein caustic salt used is
selected from caustic soda, caustic potash of commercial grade.
3. A novel process as claimed in claims 1 to 3 wherein leaching is done with pulp
density in the range of 1.30 to 1.60 gm/cc.
4. A novel process as claimed in claims 1 to 4 wherein leaching is done for a period
of 4-6 hours.
5. A novel process as claimed in claims 1 to 5 wherein polymetallic manganese sea
nodule concentrate is dried at a temperature in the range of 110 to 120°C for 4
to 6 hours.
6. A novel process as claimed in claims 1 to 6 wherein caustic solution is recovered
from leach liquors by conventional methods and after purification is recycled.
7. A novel process for concentration of polymetallic manganese sea nodules for
extraction of valuable metals like nickel, copper, cobalt and manganese
substantially as herein described with reference to examples.

Documents:

531-del-2000-abstract.pdf

531-del-2000-claims.pdf

531-del-2000-correspondence-others.pdf

531-del-2000-correspondence-po.pdf

531-del-2000-description (complete).pdf

531-del-2000-form-1.pdf

531-del-2000-form-19.pdf

531-del-2000-form-2.pdf

« Previous Patent

Next Patent »

Patent Number

230912

Indian Patent Application Number

531/DEL/2000

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

28-Feb-2009

Date of Filing

25-May-2000

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG, NEW DELHI-110001, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	SAHA ANIL KUMAR	NATIONAL METALLURGICAL LABORATORY, JAMSHEDPUR – 831007, BIHAR, INDIA.
2	KHAN ZAHID HUSAIN	NATIONAL METALLURGICAL LABORATORY, JAMSHEDPUR – 831007, BIHAR, INDIA.
3	PREMCHAND	NATIONAL METALLURGICAL LABORATORY, JAMSHEDPUR – 831007, BIHAR, INDIA.

PCT International Classification Number

C22B 15/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA