A trail was carried out on reducing the volatile organic compounds
(VOCs) during the maturity stage of different composted organic wastes
(i.e., town refuse, sugarcane factories, animal residues and plant residues)
by using three kinds of clay minerals (i.e., montmorillonite, kaolinite and
attapulgite) as a natural remediation. The total released volatile organic
compounds as air organic pollutants from each of the tested composted
organic wastes were determined by using the GC-mass method. The
released VOCs are namely ethanol, acetic acid, acetone, n-propanol,
cyclohexane, n-heptane, octane, benzene, chlorobenzene, ethylbenzene,
toluene, dichloromethane, xylene, methyl chloride and trichloroethane.
The obtained data showed that the released VOCs recorded the
greatest values in case of the composted sugarcane wastes, while the
lowest ones were associated with the composted town refuse wastes. On
the other hand, the composted animal and plant residues exhibited values
of released air volatile organic pollutants represent an intermediate case
between the other composted organic substances. Thus, it could be
arranged the different studied composted organic wastes according to the
released amounts of VOCs values in an ascending order of composted
sugarcane wastes > composted plant residues > composted animal
residues > composted town refuse wastes.
Accordingly, composted sugarcane wastes that showed the greatest
released VOCs values were chosen for a natural remediation by using the
tested clay minerals (i.e., montmorillonite, kaolinite and Attapulgite) at
applied two rates of 5 and 10 % and during two interval periods of 24 and
48 hours. The obtained results showed that the percentages of released
VOCs as a result of treating composted sugarcane wastes with the clay
minerals of montmorillonite, kaolinite, and attapulgite at the rates of 5 &
10 % reached 91.20 & 87.50, 78.76 & 60.42 and 52.46 & 35.42 % of the
released amounts from the untreated ones at the fixed time of 24 h vs the
corresponding values of 9.49 & 8.38, 6.25 & 6.04 and 5.89 & 4.06 % at an
interval period of 48 h, respectively. So, it could be categorized the tested
clay minerals as a natural remediation according to their immobilization
for the released VOCs into an ascending order: attapulgite > kaolinite >
montmorillonite.