The methods by which we can reduce carbon footprint in our life, in environments as well. some unknown methods to get frequented. made by IIT Kharagpur students..

1. LOW CARBON FOOTPRINT IN
METAL EXTRACTION
BY
-KHILESH KUMAR BHANDARI (10MT10021)
-KRISHNA KUMAR HANSDAH (10MT10022)
-BHAGAT LAL TUDU (10MT30004)

2. CARBON FOOTPRINT
The total amount of green house gas
produced to directly and indirectly support
human activities , usually expressed in
equivalent tons of carbon dioxide (CO2).

3. GLOBAL WARMING POTENTIAL
Global-warming potential (GWP) is a relative
measure of how much heat a greenhouse gas traps in
the atmosphere.
For example, the 20 year GWP of methane is 72, which means
that if the same mass of methane and carbon dioxide were
introduced into the atmosphere, that methane will trap 72 times
more heat than the carbon dioxide over the next 20 years

5. SCRAP METAL RECYCLE
• Pressing
• Crushing
• Shearing
• Sorting
• Smelting

6. Sorting Smelting
Finished products

7. The biggest savings are with aluminium where the recycled only takes 6%
of the energy, but other pollution is caused in the production both times.12
kg of CO2 are produced per kg aluminium from bauxite but only 1.7 kg CO2
from recycled aluminium. Pollution
Carbon Footprint
Kgs of CO2 produced per kg of metal
Aluminium from bauxite 12
Aluminium recycled 1.7
Brass from ores 6.7
Brass recycled 1.7
Carbon Footprint
Steel from ore 2.82
Steel recycled 0.5
Carbon Footprint
Kgs of CO2 produced per kg of metal
Copper from ore 5.5
Copper recycled 1.4-4
Carbon Footprint
Aluminium has the highest CO2 production per kg but it is much lighter than
most metals.

8. Biohydrometallurgy
Biohydrometallurgy can be defined as the field of applications resulting from
the control of natural (biochemical) processes of interactions between
microbes and minerals to recover valuable metals.
 It is a subfield within hydrometallurgy which includes aspects of
biotechnology.
 It is used to perform processes involving metals, for example,
microbial mining, oil recovery, bioleaching, water-treatment and
others.
 It is mainly used to recover certain metals from sulfide ores.
 It is usually utilized when conventional mining procedures are too
expensive or ineffective in recovering a metal such
as copper, gold, lead, nickel and zinc.

9. BIOLEACHING
Bioleaching is the extraction of metals from their ores through the use of living
organisms. This is much cleaner than the traditional heap leaching using
cyanide.Bioleaching is used to recover copper, zinc, lead, arsenic, antimony,
nickel, molybdenum, gold, silver, and cobalt.
Bioleaching techniques
Role of microorganisms in mineral bio-oxidation:
• Microbes produce the leaching chemicals.
• Microbes also provide the most efficient reaction space for
bioleaching to occur

10. Cu2+(aq) + 2LH(organic) → CuL2(organic) + 2H+(aq)
Because this complex has no charge, it is no longer attracted to polar water
molecules and dissolves in the kerosene, which is then easily separated from
the solution
Cu2+(aq) + Fe(s) → Cu(s) + Fe2+(aq)

11. The bacterium Paenibacillus polymyxa
grown in the presence of hematite.

13. BENEFITS OF BIOLEACHING
• Simple and inexpensive process. Substantially lower capex and
opex than in traditional smelting and refining processes
• No sulfur dioxide emissions as in smelters.
• No need for high pressure or temperature
• Leaching residues less active than in physico-chemical processes
• Ideal for low grade sulfide ores – lower cut-off rate possible

14. BACTECH BIOLEACH PROCESS

15. Nanoscavengers - a simple approach to
metal extraction
SEM image of the
HOC18-nanoscavenger
This method, termed the nanoscavenger concept, is based on silica particles and
is an easy, green approach to the collection and concentration of metals for
analysis. The technique is expected to yield both environmental and cost
benefits.
Analytical chemists regularly need to remove metals from aqueous solutions so
they can be analysed. Extraction into organic solvents is currently the most
popular procedure for doing this.
Howard and Khdary's approach uses chelating organic ligands to modify the
surface of silica spheres with an approximate diameter of 250 nm. These
particles are able to bind to metals temporarily, and can be collected easily
from solutions.

16. The concept behind this research is beautifully simple. The nanoscavenger moves
naturally through the solution under examination, binding any metal with which it
comes into contact. This movement, using Brownian motion, means that no physical
agitation is required. Simple filtration removes the metal-bound nanoscavenger
from the solution. Finally, separation of the metal and nanoscavenger allows
analysis of the metal using standard detection methods.
A wide range of organic materials can be extracted on the surface of
nanoscavengers by hydrophobic interaction. This is can be achieved by modifying of
the silica surface with different organic groups. Indeed, large particle size modified
silica has been widely and successfully used for the pre-concentration of drugs and
pesticides.

17. ADVANTAGES OF NANOSCAVENGING
TECHNIQUE
 the technique is environmentally friendly as smaller volumes
of organic solvents are used than with the other extraction
methods and only small quantities of nanoscavenger (50-200
mg) need to be dispersed.
 Large numbers of samples can be quickly and simultaneously
treated, even at the sampling site.
 One of the most important physical advantages of this
procedure is less human or mechanical effort is needed as no
mechanical agitation is required.

18. REDUCTION OF CO2

19. THANK YOU