Review of Related Literature: Latundan Banana Peel As Lead Adsorbent
Review of Related Literature: Latundan Banana Peel As Lead Adsorbent
Review of Related Literature: Latundan Banana Peel As Lead Adsorbent
CHAPTER II
REVIEW OF RELATED LITERATURE
The atomic number of lead is 82. It is soft, malleable poor metal; lead is a group
4A element in period 6. It has a bluish white color when freshly cut, but varnishes to a
dull grayish color when exposed to air. Lead has poor electrical conductivity) (Brady J.E
and Hoslum J. R: 1996). Lead has been commonly used for thousands of years and
Metallic lead occurs in nature although it is very rare. It is usually found in ore
with zinc, silver and copper and is extracted together with these metals. The main lead
mineral is galena (PbS), which contains 86.6% lead. Other common varieties are
cenissite (PbCO3) and anglesite (PbSO4) (Brady J.E and Hoslum J. R: 1996)
Lead is used frequently in polyvinyl chloride (PVC) plastic, which coats electrical
cords, also as projectiles for fire arms and fishing sinkers because of its density. It is
Lead is a major constituent of the lead-acid battery used as a car battery. It is used as
a coloring element in ceramic glazes, notably in the colors, red and yellow (Stellman J.
M : 1998).
LATUNDAN BANANA PEEL AS LEAD ADSORBENT
Lead is very malleable and can be used widely in building construction e.g
Lead poisoning typically results from ingestion of food and water contaminated
with lead; but may occur after accidental ingestion of contaminated soil, dust or lead
based paint. Lead can damage nervous connections (especially in young children) and
Meanwhile, lead is a soil contaminant; its presence in natural deposits enters the
soil through gasoline (leaded) leaks from underground storage tanks or through a waste
stream of lead paint or lead grindings from industrial process or lead pipes.
Past research had shown that coconut fibers, peanut shells and other plant
materials could remove potentially toxic heavy metals such as lead and copper from
water. Mines, factories and farms can all generate such waste, with the potential to
harm one's health and the environment. And current methods for purifying water of
heavy metals are expensive, with some materials used in the process being poisonous
themselves.
LATUNDAN BANANA PEEL AS LEAD ADSORBENT
compounds such as carboxylic acids. These acids are charged such that their
negatively charged electron pairs are exposed, meaning they can bind with metals in
the water that usually have a positive charge. (Gustavo Castro, Sao Paulo State
University)
The researchers found that minced banana peel performed as well or better at
removing copper and lead than many other filtering materials, quickly removing both
from water in The Parana River in Brazil. (Gustavo Castro, Sao Paulo State University)
Researchers from the Bioscience Institute at Botucatu, Brazil, said that the skins
can outperform even conventional purifiers such as aluminum oxide, cellulose and
silica. These have potentially toxic side effects and are expensive.
The team’s method follows previous work that showed that plant parts, such as
apple and sugar cane wastes, coconut fibers and peanut shells, can remove toxins from
water.
These natural materials contain chemicals that have an affinity for metals.
“I was at home eating bananas when I had the idea: why not make something
with this?” Gustavo Rocha de Castro, a researcher at the institute and co-author of this
De Castro and colleagues dried the peels in the sun for a week, ground them and
added them to river water containing known concentrations of copper and lead. They
found that the peels absorbed 97 per cent of the metals after just one hour.
The peels were tested in the lab and worked perfectly. Eventually their efficiency
reduces, at which point the metals should be removed from the skins so they can be
disposed of safely.
Castro said that, although the peels were tested only on copper and lead, the
results are very promising, and the banana peel process has proven to be a cost-
According to Liesl Clark, banana peels can also be natural alternative sources of
some polish, teeth whitener, and a tomato plant fertilizer. It also has compunds that can
be used as insecticides. (L. Clark, 2013) Banana peels are alsogood in depression,
sleeping better, lowering cholesterol, and being safe from cardiovascular diseases. (Dr.
Haider, 2013)
Studies have found that banana peels contain more tannin compared to the fruit
itself. Tannins are in great use for food preservation, and an element of an insecticide.
(H. M., 2013) Also, researchers found out that the fruit peels have collected all te
insecticidal residue when they are compared to the fruit inside it. (H, M., 2013)
LATUNDAN BANANA PEEL AS LEAD ADSORBENT
A study once concluded that banana peels, a waste material, have good potential
as an adsorbent to remove toxic metals like co2+ and Ni2+. (Universal Journal of
Chemistry, 2013)
According to a study, bio-adsorbent made from banana peels and stems have
ability to absorb copper metal. (Hasanah et.al, 2012) Also, banana peels have the ability
to remove chromium in water. Chromium is toxic, corrosive and irritant. (J. Memon,
2008)