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The batch adsorption technique investigated the efficiency of sawdust adsorbent for removing copper ions from synthetic solutions. A chemical synthesis process prepared the activated sawdust powder, and its surface area and pore volume were obtained by BET isotherm analysis. The ability of copper ion uptake by activated sawdust powder was examined under the characterization study of SEM, EDX & FTIR studies. Various isotherm studies checked the process of adsorption, and the kinetic studies confirm the nature of the adsorption process with sawdust adsorbent. Thermodynamic studies were used to analyze the endothermic nature of the adsorption process, and 0.3 N of H2SO4 acid desorbs 93.27% of copper ions from the spent adsorbent. The experimental study confirms the better adsorption ability of sawdust powder in the activated charcoal form to remove the heavy metal pollution in aqueous solutions.

The commercial imidacloprid (IMD) insecticide [1-(6-chloro-3-pyridinyl) methyl-4,5-dihydro-N-nitro-1H-imidazole-2-amine] is widely used for the enhancement of crop production, but the intensive use of this insecticide has caused serious environmental problems. This work presents an electrochemical process for the removal of this insecticide using galvanostatic electrolysis at modified tantalum surface by lead dioxide film anode (Ta(PbO2)) anode. The electrolytic process was monitored by chemical oxygen demand (COD). The influence of operating parameters, such as current density, initial concentration of IMD, temperature and initial pH value was investigated. The COD decay follows a pseudo first-order kinetic and the process was under mass transport control. COD removal reach 97% when using an apparent current density of 100 mA cm−2, initial COD of 953 mg L−1 and at 25 °C after 4.5 h electrolysis time.

The nanocomposites of poly(o-chloroaniline) with titanium dioxide have been prepared via chemical oxidative polymerization technique using o-chloroaniline monomer and titanium dioxide nanoparticles for photocatalytic application. The different composites were prepared by varying the load percentage of titanium oxide nanoparticles (TiO2 NPs) in polyorthochloroaniline (POCA) matrix. The synthesized composite materials were characterized by Scanning electron microscopy (SEM), X-Rays diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The POCA/TiO2 nanocomposites were further applied to evaluate the photocatalytic degradation potential towards direct yellow 50 (DY50) dye in an aqueous medium under ultraviolet radiations.

Different aquatic ecological zones exhibit different gradients present heterogeneous algal composition. The algal community in the water column and sediment with certain environmental factors were screened monthly for twelve months with standard methods, to ascertain disparate in algal distinction. Air and water temperature, conductivity, water depth, dissolved oxygen and nutrients were the primary factors that influenced the algal abundances and diversities. 90% of the algal communities were benthic (33 species) and planktic-benthic (21) with 10% truly planktonic (6) species. Comparatively, the water-column benthic and planktic-benthic surpasses the benthic species associated with the sediment. The PCA on the habitat- type abundance revealed that 99.5% benthic algae in the water column are responsible for the total algal- abundance variance. Species richness and Shannon diversity indices were low, which ANCOVA and Levene tests demonstrated significantly equal and homogeneity of algae respectively between the studied zones. The linear relationships between the algae in the water and sediment zones were non-significant (p>0.05). The Euclidean algorithm confirmed algal community similarity in the water column and sediment. Species diversity limits, a high proportion of benthic algae in the planktonic, and significant homogenous algae in water and sediment. Signatures sediment destruction, breaking and dislodgement and uplifting of associated bottom algae, and the constant mixing of the water column and sediment due to sand dredging in the study area. Machines and human-dredging has exacerbated the abundance of benthic algae in the water column.