A critical review on clay-based nanocomposite particles for application of wastewater treatment

Nanotechnology plays an important function in recent environmental aspects for the elimination of contaminants in the ecosystem. In recent times, nano-clay has initiated more concentration because of its distinctive physicochemical properties and characteristics. Recently, many types of research in clay-based nanocomposite were accomplished in the elimination of pollutants from water sources. Nanocomposite materials have advanced properties useful for contaminat removal such as higher surface area, thermal stability, selectivity to remove different contaminants, improved process ability, and fast decontamination. Thus, the development of clay-based composite materials is one of the upcoming directions to use effectively in water and wastewater treatment as adsorbent nanomaterials. This paper assesses the latest achievement in clay-based nanocomposite preparation, material property analysis and function for various pollutant removals. In particular, great consideration was paid to the recent progress in clay/metallic, clay-polymer, and clay-carbon composites presenting their application in the removal of different kinds of pollutants. Moreover, the mechanism of adsorption, the challenges and future perspective were also discussed to reach the optimum performance of the nanomaterials adsorbent. It is confirmed that clay-based nanocomposite materials are more cost-effective technology than conventional treatment methods.

Chromatographic and spectroscopic determination of solvent-extracted Lantana camara leaf oil

Objective

This study aimed to determine the chemical profile of Lantana camara leaf oil.

Methods

The essential oil was extracted from dried leaf samples using the Soxhlet extraction method. The oil was separated from the solvent and the bioactive compounds were identified using gas chromatography–mass spectroscopy (GC-MS) and Fourier transform infrared spectroscopy (FTIR). The identified peaks in the mass spectrum were matched with the database of the US National Institute of Standards and Technology (NIST) library.

Results

The FT-IR results indicated the presence of alcohols, carboxylic acids, phenols, alkanes, ketones, and primary amine compounds. GC-MS identified 43 compounds representing 95% of the total leaf essential oil components. Some of the major isolated compounds included a pyrrolizine; 1-dodecanol; 1,2-nonadecanediol; phytol; 1,3-dioxolane; 4-undecene, 9-methyl, (Z)-; 1-eicosanol; and imidazole.

Conclusions

The identified constituents of the extracted oil have established pharmacologic and insecticidal activities, and these compounds are also used in the drink, food, and cosmetic industries. This extract is highly valuable for the medical treatment of various ailments.

Utilization of treated coffee husk as low-cost bio-sorbent for adsorption of methylene blue

Dyes and pigments have been used in many industries for colorization purpose but they pose hazards to the environment and end users of water. Therefore, it is important to remove this pollutant from waste water before their final disposal. This study aimed to investigate the removal of methylene blue by cost effective, ecofriendly, high-efficiency bio-sorbent from activated coffee husk. The process was carried out using chemical activation (H3PO4) process. Fourier transform infrared spectroscopy and surface analyzer (Brunauer-Emmett-Teller) were used to characterize the adsorbent. The specific surface area adsorbent was obtained as 28.54 m2/g. The maximum removal efficiency was obtained as 96.9% at pH of 5, initial dye concentration of 20 mg/L, adsorbent dosage of 0.8 g/50 mL, for contact time of 50 min and 30°C temperature on the activation surface of coffee husk. Langmuir model was found to fit the equilibrium data for methylene blue adsorption with 6.82 mg/g at 30°C. The adsorption process follows the pseudo-second-order model. Thermodynamics analysis showed that the adsorption of methylene blue on to the activated coffee husk was a spontaneous and endothermic process. The experimental data obtained in the present study proved that coffee husk is a suitable bio-sorbent in removal of cationic dyes.

Insecticidal activity of Lantana camara extract oil on controlling maize grain weevils

Postharvest losses are known to be one of the serious constraints upon food security among farmers poor resource in Africa. The use of botanical insecticide in pest management during storage against weevils is often encouraged because synthetic insecticides produce multiple side effects on human and environment. In this study, the insecticidal property of methanol, ethanol, and ethyl acetate extracts of Lantana camara leaf oil and powder for controlling maize weevils, Sitophilus zeamais, was studied. Gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy (FTIR) were used to identify the chemical composition and functional group of solvent extract, respectively. Adult weevil repellency and mortality were studied by the effect of oil concentration at 0% (w/w), 2% (w/w), 3% (w/w), 5% (w/w), 7% (w/w), and 10% (w/w). Repellency effect was also conducted at 6, 12, and 24 h. The number of weevil death increased significantly as exposed time was increased. The extracted oil by the three-solvent fraction had direct repellent and toxic effect to the weevil. From all treatment applied, extracted by methanol fraction had showed highest percentage mortality (74%). The lowest mortality rate was observed in ethyl acetate extract (26%) at 2% (w/w) concentration. The effect of leaf powder and extracted oil on repellency and mortality for insects was due to the presence of bioactive and phytochemical molecules such as Phytol, Pyrroline, Paromomycin, Pyrrolizin, and 1-Eicosano. It was concluded that both L. camara leaf powder and extract oil can be used for the protection of stored maize from infestation S. zeamais.

Data set on performance evaluation of discharged wastewater quality from Guna water treatment plant for potable water purpose

This article provides to evaluate the quality of discharged water from Guna spring water treatment plant and to compare with WHO drinking water standards and Ethiopian bottled drinking water specification to reuse for potable water purpose. The discharged waste water quality analysis was conducted by Physical, Chemical, Biological and Bacteriological parameters of water in association with set of standards. Atomic adsorption spectroscopy (AAS), Flame photometer, UV–Visible spectrometer and Photo meter were used for characterization discharged water. All water quality parameter was determined in all unit process (softener, sand filter, activated carbon and ultra-filter). Bacteriological analysis (total coli form, fecal coli form and Escherichia coli type1) were conducted. During discharge water quality analysis, the effect of flow rate (2 m³/h, 4 m³/h and 6 m³/h) and discharge time (5,10 and 15 min) have been performed. We provided data set about Atomic adsorption spectroscopy (AAS), Flame photometer, Turbidity meter, Photometer and Bacteriological analysis parameter were verified.