Removal of Zn(II), Cu(II), Chemical Oxygen Demand (COD) and Colour from Anaerobically Treated Palm Oil Mill Effluent (POME) using Microwave Incinerated Rice Husk Ash (MIRHA)

Many have known and may have realized what heavy metals can cause to human
bodies and the environment. The effect caused by heavy metals has become more severe
day by day because of the rapid growth of technology which requires usage of these
materials and low awareness upon minimizing their effect to human bodies.
Nonetheless, research has been conducted in many parts of the world to remove or
minimize the effect of heavy metals toward the environment. Therefore we have seen
that many technologies have been introduced to attain its purpose. Effective coagulation
technology, membrane filtration technology, ion exchange, electro dialysis, and reverse
osmosis are some examples of removing heavy metals from the water. About 3 tonnes of
POME was produced for every ton of oil extracted in an oil mill. The POME produced
contains high concentration of Chemical Oxygen Demand (COD) and color. The
objective of this paper was to use the microwave incinerated rice husk ash (MIRRA) as
a recycled adsorbent in removing Cu(II), Zn(II), COD and color from treated POME
wastewater. Rice husk were burned at 800°C temperature to produce MIRRA and it was
then soaked overnight in H2S04. The effect of various dosages of MIRRA and contact
time on removal of Zn(II), Cu(II), COD and colour from POME were conducted by
batch study. The highest Cu(II) removal of 88% was achieved at 50000 mg/L dosage of
MIRRA at 12 hr contact time. While for Zn(II), 74% removal was achieved at
50000 mg!L dosage of MIRRA at 18 hr contact time. Optimum removal of COD ( 41%)
and colour (88%) was achieved at 40000 mg/L and 50000 mg/L dosage of MlRHA at
6 hf: contact time, respectively. MIRRA proved to be effective in removing Zn(II),
Cu(II), COD and colour from POME wastewater.