This document discusses the environmental impacts of increasing carbon dioxide (CO2) concentrations, focusing on global warming and ocean acidification, and presents a study conducted along the coast of Visakhapatnam. It explores the mechanisms of CO2 as a pollutant, its sequestration methods, and the resulting changes in ocean chemistry, including the decline of carbonate ions. The conclusion emphasizes the need for regulation of CO2 emissions and future research directions to further understand the implications of acidification.

1. SOMA SEKHAR SRIADIBHATLA
DEPARTMENT OF ENGINEERING CHEMISTRY,
ANDHRA UNIVERSITY COLLEGE OF ENGINEERING.
- EFFECT ON ENVIRONMENT AND
ITS SEQUESTRATION.
*AWARDED BEST PRESENTATION

2. OUTLINE
 INTRODUCTION
 CO2 … A POLLUTANT???
 CONSEQUENCES
GLOBAL WARMING.
OCEAN ACIDIFICATION.
 SEQUESTRATION
 CONCLUSIONS
 FUTURE ENVISIONS
 REFERENCES

3. INTRODUCTION
 This paper focuses on some of serious environmental
consequences due to carbon dioxide, which is increasing at an
alarming rate. Carbon dioxide sequestration technique is also
discussed.
 The serious environmental consequences like Global warming,
Ocean acidification are discussed.
 Decalcification process due to Ocean acidification along the coast of
Visakhapatnam and the affinity of CO2 towards sea water is studied
in comparison with other water samples and the results are
discussed.

4. CO2 … A POLLUTANT???
 [1]CO2 accounts for less than 1% of total atmospheric gases, its about
391 ppm by volume as of 2011. It rose by 2.0 ppm per year during
2000 – 2009.
 The numbers were below 300(ppm) i.e. below 0.03% by volume
before industrialization.
 Due to rapid industrialization and increase in traffic the percentage of
carbon dioxide is also increasing in atmosphere.
 Due to which green house effect is also increasing making earth
warmer.
 Oceans act a sink for carbon dioxide, so the dissolution of carbon
dioxide is increasing leading to the lowering of pH.
[1] The keeling curve of atmospheric CO2 concentrations measured at the Mauna Loa Observatory,
Hawaii. Tans Pieter, “Trends in carbon dioxide”.

5. This is for the year 2000 given by Environmental Protection Agency, USA.

6. CONSEQUENCES:
GLOBAL WARMING
It is important consequence faced due to the increase in the
concentration of CO2. Global warming is the increase in the
average temperature of earth’s surface air and oceans.
According to the 2007 fourth assessment report by
Intergovernmental panel on climate change ( IPCC) global earth
temperature has increased 1.3F last year and if it increases in
such a manner then by 2100 it will increase between 2&11.5 F.
GAS CONTRIBUTION
CO2 9-26%

7. MECHANISM
 The atmosphere of earth is like membrane of gases monitoring the entry and
exit of solar radiation. Some gases which do monitor the radiation within the
thermal infrared range are green house gases.
 These green house gases are transparent to the sunlight coming in but they
strongly absorb the infrared radiation, which earth sends back as of longer
wavelengths. This trapping of heat causes warming of earth. C02 absorbs I.R
radiation in the range 12000 - 16,300 nm.
 It has been calculated that with a doubling of C02 concentration, the
temperature of earth’s surface increases by 1.9c.
 The computer modeling indicates following effects due to global warming:
Melting of polar ice caps, dry areas becoming drier, drastic drop in food
production, and expansion of oceans.

8. OCEAN ACIDIFICATION
 Oceans act as natural sink for carbon dioxide.
 As, the percentage of carbon dioxide in air increases its dissolution
increases leading to the lowering of the pH (formation of carbonic acid),
the hydronium ions concentration in the medium increase.
 The process of maintaining constant pH by oceans is disturbed and the
concentration of carbonate ions decrease and if this decrease is below
the saturating concentration of carbonate ions then decalcification
takes place.
 The organisms like corals, calms etc are effected as a result of
decalcification.
 This process of ocean acidification is studied along the coast of
Visakhapatnam.
 The alkalinity test is done and the concentrations of carbonate and bi-
carbonate ions are calculated in collected samples & the pH of these
samples are also noted down.

9. RESULTS
 pH of sea water samples collected on December(2010), January to
August(2011).
MONTH SAMPLE pH
DEC NO.1 8.14
JAN NO.2 8.14
FEB NO.3 8.14
MAR NO.4 8.14
APR NO.5 8.13
MAY NO.6 8.13
JUN NO.7 8.13
JUL NO.8 8.13
AUG NO.9 8.13
(Note: These samples were collected on dry days; sample no
5,6,7,8,9 were collected from a different point i.e.in main city)
MONTH SAMPLE pH
JUN NO.10 8.11
JUL NO.11 8.12
AUG NO.12 8.12
(Note: These samples were collected after rain)

10. CARBONATE IONS CONCENTRATION
Sample no concentration
1 95ppm
2 94ppm
3 94ppm
4 94ppm
5 90ppm
6 90ppm
7 90ppm
8 90ppm
9 90ppm
10 84ppm
11 84ppm
12 84ppm
Sample no concentration
1 58ppm
2 59ppm
3 59ppm
4 59ppm
5 61ppm
6 61ppm
7 61ppm
8 61ppm
9 61ppm
10 64ppm
11 65ppm
12 65ppm
BICARBONATE IONS CONCENTRATION.

11. 0
1
2
3
4
5
6
7
8
9
sea water municipal
water
distilled water rain water
before
after
difference
FIGURE ; showing the affinity of carbon dioxide toward sea water sample in comparison to other water samples.

12. CARBON DIOXIDE SEQUESTRATION
 The process of trapping of carbon dioxide is important to reduce its
percentage in atmosphere. The trapping can be done using adsorbents like
hyper branched amino silica* capable of capturing CO2 reversibly. The CO2
which is captured can be refined and stored. The captured CO2 can be used
for many commercial purposes like: as pressurizing agent for enhanced oil
recovery in oil drilling process, preparation of synthetic gas, dry ice,
production of biodiesel.
 To explain this technique C02 gas can be pumped into barium hydroxide
solution and white ppt. of barium carbonate formation is seen, which on
calcination we can regenerate C02 gas, which is a simple laboratory
experiment.

13. CONCLUSIONS
o Carbon dioxide is a potent pollutant , whose emission has to be regulated.
 Global warming is a serious issue which should be dealt immediately,
 Ocean acidification is due to increase in carbon dioxide percentage.
 The affinity of CO2 is more for sea water when compared to other water samples.
 As the acidity of sea water increases the carbonate ion concentration decreases.
 The concentration of bi-carbonate ion increases.
 The pH of sea water samples collected soon after rain is less and the concentration of carbonate
ions concentration is also less than that of samples collected on a dry day.
 Grow plants, Go Green.
 Our motto being earthlings should be , “ to maintain clean, green & cool earth”.

14. FUTURE ENVISIONS
 To calculate the percentage of carbon dioxide in Visakhapatnam and to study
the increase in its concentration.
 To elute out carbonic acid by using XRF.
 To study the salinity of the samples collected.
 To enhance the sensitivity of pH calculations and to use new methods to
calculate the carbonate & bi carbonate concentration.
 To prolong this study of acidification process.

15. REFERENCES
 S.A.Soma sekhar*,A study on ocean acidification due to carbon dioxide along the coast of
Visakhapatnam (urban), journal of environmental research and development.
 S.A.Soma sekhar*, Environmental impact of oil industries, Indacon.
 IPCC AR4 SYR , journal of American chemical society.
 NOAA report.
 Ocean acidification- decalcification, hoegh-guldberg.o.et al,science,318,1732-1742(2007).
ACKNOWLEDGEMENT
 Department of Engineering chemistry, Dept. of Chemical Engineering, Andhra University.
NCCCM BARC, Hyderabad. Dr. I. Nageshwar Rao , UGC Scientist, Marine Chemistry, Andhra
University. Jadhavpur University, Kolkata. Delta Institute, Andhra university.