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In view of the global need to curb the effect of contaminants in waste water on our environment, the adsorption potentials of modified carbon from bambaranut (Vigna subterranean) shell was investigated for its efficiency in the removal of methylene blue from waste water. The adsorbent morphology and surface chemistry were established by Brunauer-Emmett-Teller (BET) determination and Scanning Electron Microscopy (SEM), as well as other standard laboratory procedures. The prepared material was used for the uptake of MB from aqueous solution in a batch process, using UV spectrophotometer Model 752 at 620nm to analyze for the residual dye concentration. The effect of operational parameters such as contact time, adsorbent dosage, initial dye concentration and pH were analyzed to determine the factors controlling the rate of adsorption. Results from the study showed that the active carbon prepared was a porous material, with surface area of 193 m²/g, average pore size of about 10.98nm, and pore volume of 0.530cm³/g. With increase in initial dye concentration from 15mg/l to 75mg/l, a decrease in percent adsorption from 95.4% to 72.19% was observed. Increase in adsorbent dosage (from 0.1g to 0.5g), contact time (from 5 min to 40 min) and pH from 2 to 10 resulted in increase in percent adsorption from 84.03% to 98.83%, 54.24% to 84% and 48.17% to 84.03% respectively. About 98.83% removal of MB dye was achieved after 20 min, at pH of 6, temperature of 27±2^oC, 0.5g weight of adsorbent and initial concentration of 60mg/l of 50ml MB dye solution. Langmuir isotherm best fits the equilibrium adsorption data with R² = 0.996; the adsorption intensity obtained from Freundlich model (n>1) and the energy of adsorption obtained from the D-R model (< 8kJ/mol) suggested that physisorption dominates the adsorption of methylene blue onto the prepared activated carbon. Adsorption kinetic data was best described using Pseudo second order kinetic model (R² = 0.996), giving equilibrium rate constant (k₂) of 7690g mg^-1 min^-1. The characteristic results showed that bambaranut shell can be employed as an alternative to commercial adsorbents in the removal of methylene blue dye from aqueous solutions and waste water.

As part of the current research for more effective antimalarial drug, Cu (II) complex of sulphamethazine with 1,10 phenanthroline was synthesized. The novel complex was characterized by Elemental analysis, FT-IR and electronic spectroscopy. The novel complex is insoluble in water, which is an indication of covalent and non- electrolyte character. The elemental analysis result of the complex correspond with the proposed formula [Cu(SUF)(phen)(SCN)₂]. The electronic spectrum of sulfamethazine and 1, 10- phen showed absorption bands at 212 nm (47169 cm⁻¹) and 306 nm (32679 cm^–1). These bands were assigned to the n – δ* and π – δ* transitions. The infrared bands were seen at 3443 – 3344 cm ⁻¹which were attributed to the presence of v(NH2), v(NH) and v (OH) vibrations experience bathochromic shift in the metal complex. The parent ligands acted as a bidentate chelating agent showing coordination through the pyridine nitrogen and the nitrogen of the NH moiety in this case.

Coastal area of Bangladesh is one of the significant ecologically productive areas and full of rich biodiversity that includes variety of species that are endemic to this region. The Shipbreaking activity has turned out to be more significant within the economic situation of the poverty-stricken Bangladesh. The study vicinity was alienated into the Shipbreaking zone and control site for proportional investigation. The study was administered to assess the changing pattern of the concentration of trace metals in soil Soil samples of the study areas and its impact on fish diversity of the ship breaking area in Bangladesh over the 40 years. From the finding of the study, it had been found that the concentration of the heavy metals found within the ship breaking area followed a pattern within the following fashion Fe>Pb>Cr>Mn>Zn>Ni>Cu>Cd>Hg. The finding of this heavy metal analysis of sediments demonstrated that there has been in an increment of two to eight times of selected heavy metals from the finding of 1980 to 2019. The study compared with the two relatively pristine or less impacted (undisturbed) areas, that served because of the reference zone. These studies also found that about 30 species of fishes became irregular or are threatened with extinction than they were 40 years ago.

Adsorbents were derived from banana peel through chemical treatment using phosphoric acid, potassium hydroxide, and sodium hydroxide to adsorb methylene blue from water. The adsorption of methylene blue was performed at varying concentrations and contact times. The equilibrium data fitted well with Langmuir equation, with a maximum monolayer adsorption capacity of 99.28 mg/g (28%). Phosphoric acid-treated adsorbent exhibits a greater capacity despite a lower affinity than the other adsorbents. A two-stage batch adsorber model was developed to optimize the adsorbent dosage for performance evaluation. Banana peel is a promising resource of adsorbent for wastewater treatment.