2.2 Adsorption Studies
The experiments were conducted in a batch mode to check the applicability of
activated carbon and fly ash as an adsorbent for the removal of acid magenta dye
from aqueous solution. The effect of different parameters such as contact time
(30–150 min), dye concentration (20–60 ppm), adsorbent dose (0.5–2.5 g), pH
(from pH 2 to 10), and temperature (30–70
C) was investigated for the removal of
acid magenta dye. In the batch adsorption study, 100 mL of acid magenta dye
solution of different concentrations (50, 100, 150, and 200 ppm) was placed in
four different Erlenmeyer flasks (250 mL capacity) with different amount of activated carbon and fly ash (0.5, 1.0, 1.5, 2.0, and 2.5 g), respectively. The mixture was
placed in an incubator shaker at 120 rpm until equilibrium was observed to be
attained. The conical flasks were withdrawn at regular time interval, and analysis of
the sample was made by following standard procedure. The pH of the solution was
maintained by using 0.1 N HCl and 0.1 N NaOH solution.
Removal efficiency was calculated by the following formula:
Removal of Acid magenta dye %
ð Þ ¼ C 0 À C t =C 0 Â 100
where C 0 and C t are initial and final concentrations of acid magenta dye at time t in
mg/L in the sample, respectively. All the measurements were done for three times,
and mean values were presented.
2.3 Phytotoxicity Study
The toxicity of acid magenta dye before and after the treatment with activated carbon
and fly ash was studied on the seeds of mung bean (Vigna radiata). Maximum
concentration (60 ppm) of acid magenta dye was used to determine the toxicity.
2.4 Seed Germination Test
The empty and undeveloped seeds of Vigna radiata were discarded by floating in tap
water. Seeds of Vigna radiata were thoroughly washed with tap water to remove dirt
and dust for 5 min. The seeds were surface sterilized with 10:1 distilled water/bleach
(commercial NaOCl) solution for 5 min for inhibition of microbial infection and then
washed six to seven times with distilled water. Mung bean seeds were soaked in acid
magenta dye solution before and after the treatment with activated carbon and fly ash
for 4 h, respectively. The filter paper was placed in sterilized Petri dishes (20 cm
diameter) and mung bean seeds which were soaked in dye solution transferred into
Petri dishes. The Petri dishes were covered with sterilized polythene bags and kept in
264
R. T. Kapoor
The experiments were conducted in a batch mode to check the applicability of
activated carbon and fly ash as an adsorbent for the removal of acid magenta dye
from aqueous solution. The effect of different parameters such as contact time
(30–150 min), dye concentration (20–60 ppm), adsorbent dose (0.5–2.5 g), pH
(from pH 2 to 10), and temperature (30–70
C) was investigated for the removal of
acid magenta dye. In the batch adsorption study, 100 mL of acid magenta dye
solution of different concentrations (50, 100, 150, and 200 ppm) was placed in
four different Erlenmeyer flasks (250 mL capacity) with different amount of activated carbon and fly ash (0.5, 1.0, 1.5, 2.0, and 2.5 g), respectively. The mixture was
placed in an incubator shaker at 120 rpm until equilibrium was observed to be
attained. The conical flasks were withdrawn at regular time interval, and analysis of
the sample was made by following standard procedure. The pH of the solution was
maintained by using 0.1 N HCl and 0.1 N NaOH solution.
Removal efficiency was calculated by the following formula:
Removal of Acid magenta dye %
ð Þ ¼ C 0 À C t =C 0 Â 100
where C 0 and C t are initial and final concentrations of acid magenta dye at time t in
mg/L in the sample, respectively. All the measurements were done for three times,
and mean values were presented.
2.3 Phytotoxicity Study
The toxicity of acid magenta dye before and after the treatment with activated carbon
and fly ash was studied on the seeds of mung bean (Vigna radiata). Maximum
concentration (60 ppm) of acid magenta dye was used to determine the toxicity.
2.4 Seed Germination Test
The empty and undeveloped seeds of Vigna radiata were discarded by floating in tap
water. Seeds of Vigna radiata were thoroughly washed with tap water to remove dirt
and dust for 5 min. The seeds were surface sterilized with 10:1 distilled water/bleach
(commercial NaOCl) solution for 5 min for inhibition of microbial infection and then
washed six to seven times with distilled water. Mung bean seeds were soaked in acid
magenta dye solution before and after the treatment with activated carbon and fly ash
for 4 h, respectively. The filter paper was placed in sterilized Petri dishes (20 cm
diameter) and mung bean seeds which were soaked in dye solution transferred into
Petri dishes. The Petri dishes were covered with sterilized polythene bags and kept in
264
R. T. Kapoor