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Articles
by
S. Safiullah |
Total Records (
4 ) for
S. Safiullah |
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M.S. Rana
,
M.A. Halim
,
S. Safiullah
,
M. Mamun Mollah
,
M.S. Azam
,
M.A. Goni
,
M. Kamal Hossain
and
M.M. Rana
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The study focuses on potential of using crab shell chitosan as a low-cost biosorbent, for heavy metals removal from aqueous solutions in an adsorption filtration system. Chitosan was synthesized from chitin by the treatment of strong alkali solution under reflux condition and chitin was extracted from crab shell followed by decalcification and deproteinization treatment. Spectrometric (AA and UV) method was employed to detect the heavy metals concentration. Prepared 10 mg L-1 solutions of zinc, lead, cadmium, cobalt, nickel, chromium, manganese and iron were passed through the 5 g of chitosan separately and it was found that chitosan was excellent adsorbent in removing mentioned heavy metals. The removal efficiency of chitosan was in the following order Mn>Cd>Zn>Co>Ni>Fe>Pb>Cr. The result also showed that the time required for 100% breakthrough of prepared chitosan for Mn and Zn was approximately 27 and 23 h whereas it was only 16 h for both Cr and Pb, respectively. The research revealed that prepared chitosan showed better removal performance for Mn, Cd, Zn whereas the removal efficiency was satisfactory for Co, Ni and Fe but it exhibited relatively least performance for Pb and Cr. |
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M.A. Halim
,
S. Safiullah
,
M. S. Rana
and
M.A. Goni
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Iron based Titanium dioxide composites were prepared
from beach sand of Cox`s Bazaar, Bangladesh, to monitor their efficiency
in removing arsenic from contaminated water by column adsorption filtration
method in laboratory condition. It is observed that the prepared Iron
based Titanium dioxide composite (ITDO-1 and ITDO-2) can do remove 100%
both states of arsenic from the prepared 10 mg L-1 arsenic
solution up to the breakthrough volume (ITDO-1 at 3.1 L and ITDO-2 at
1.9 L, for 4 g of column material) in each case. Adsorbed arsenic is amounted
to 4871 mg kg-1 of composite ITDO-1 and removal efficiency
is found 72.46% up to the saturation volume (7.35 L) while the corresponding
figure for composite ITDO-2 is 6708 mg kg-1 of material with
an efficiency of 62.92% up to saturation volume (7.5 L). This study also
revealed that the residue (ITDO-3) left after the prepared ITDO-1 and
ITDO-2, exhibited least performance on removing arsenic. |
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M.M. Islam
,
M.A. Halim
,
S. Safiullah
,
S.A.M. Waliul Hoque
and
M. Saiful Islam
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The present research was carried out with eight specimens
of sludge from Apex Weaving and Finishing Mills Ltd. Gazipur, Bangladesh,
to determine the concentration of heavy metals (Pb, Cd, Zn, Cu, Cr, Fe
and Mn) in the sludge samples and an assessment was made with the heavy
metal content in agricultural soil. Atomic Absorption Spectrometry (AAS)
method was employed for the analysis of Pb, Cd, Cr, Zn, Cu and UV-Spectrophotometric
method was used for Fe and Mn, respectively. The mean concentration of
lead (Pb), cadmium (Cd), chromium (Cr) was 79.13, 6.27, 4.35 mg kg-1
and for zinc (Zn), copper (Cu), iron (Fe) and manganese (Mn) it was 7.90,
1.34, 195.2 and 3.97 g kg-1, respectively. All the heavy metal
concentrations except chromium in the sludge samples were higher than
that of in agricultural soil. In addition, the study concluded that pre-treatment
process for reducing the amount of heavy metal is mandatory before the
sludge can be used as a soil conditioner or fertilizer in the agricultural
soil. |
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M. Saiful Islam
,
M. A. Halim
,
S. Safiullah
,
M. Safiqul Islam
and
M. Mazharul Islam
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This study evaluated the mutual relationship among arsenic,
iron, manganese, total nitrogen and total organic carbon in the soil of
arsenic affected area, Singair, Bangladesh and the results were compared
with the other arsenic contaminated area in Bangladesh. The present investigation
revealed that high concentration of iron (9138-22071 mg kg-1)
and manganese (22-80 mg kg-1) were accompanied by the high
concentration of arsenic (44-60 mg kg-1) in arsenic polluted
Singair area. In addition, the study showed that the soil of Singair (15-20
m) contained very high concentrations of total organic carbon ranged from
23100-42900 mg kg-1 and the content of total nitrogen was also
very significant in some soil samples, where the concentration of arsenic
was high. Therefore, the research study can conclude that presence of
total organic carbon, total nitrogen, iron and manganese has significant
relationship with arsenic contamination in the soil of Bangladesh. However,
the study found no significant relationship with arsenic and carbon nitrogen
ratio in the soil of Singair. |
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