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Due to the growing concerns about pharmaceutical contamination and its devastating impact on the economy and the health of humans and the environment, developing efficient approaches for removing such contaminants has become essential. Adsorption is a cost-effective technique for removing pollutants. Thus, in this work, banana peels as agro-industrial waste were utilized for synthesizing activated carbon for removing pharmaceuticals, namely amoxicillin and carbamazepine from different water matrices. The chemically activated carbon by phosphoric acid (H3PO4) was carbonized at temperatures 350 °C, 450 °C and 550 °C. The material was characterized by several techniques such as scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), Boehm titration, point of zero charge (pHPZC), BET surface area (SBET), the proximate and ultimate analyses, X-ray powder diffraction (XRD), and thermos-gravimetric analysis (TGA). The SEM of banana peel activated carbon (BPAC) depicted a semi-regular and heterogeneous morphology, characterized by an abundance of pores with diverse forms and sizes. Boehm titration revealed an increase in the amounts of acidic groups by 0.711 mmol/g due to activation by H3PO4. FTIR recorded different peaks suggesting significant modifications in the spectroscopic characteristics of the BPAC surface due to the successful activation and adsorption of the pollutant molecules. The pHpzc of BPAC was calculated to be 5.005. The SBET surface area dramatically increased to 911.59 m2/g after the activation. The optimum conditions were 25 °C, a materials dosage of 1.2 g/L, a saturation time of 120 min, a pollutants mixture of 25 mg/L, and a pH of 5. Langmuir exhibits a slightly better fit than Freundlich with a low value of the residual sum of squares (SSE) and the data were better fitted to the pseudo-second-order kinetic. Furthermore, the efficacy of BPAC in eliminating pharmaceuticals from Milli Q water, lake water, and wastewater was successfully investigated over the seven cycles. The results of the present work highlighted a potential usage of agro-industrial waste in eliminating organic micropollutants while exhibiting sustainable management of this waste. [ABSTRACT FROM AUTHOR]

The effects of different ferrous sulfate (FeSO4) concentrations on the fatty acid profile of the blue-green alga Arthrospira platensis cultured in Zarrouk's medium to produce biodiesel were studied. Different ferrous sulfate concentrations (0, 0.005, 0.01, 0.05, and 0.1 g/L) and 0.01 g/L were examined on the biochemical composition of the alga and fatty acids profile of A. platensis. Findings revealed that the highest and lowest yields of fatty acid were 0 and 0.1 g/L FeSO4, respectively. It was also noticed an increase of palmitic acid, oleic acid, linoleic acid, γ-linolenic acid, and docosahexaenoic acid when ferrous sulfate was between 0.05 and 0.1 g/L, while these fatty acids decreased at low concentration. Ferrous sulfate at a concentration of 0.1 g/L exhibited an increase and best yields in the following: growth rate and the shortest doubling time, chlorophyll-a, phycocyanin, allophycocyanin, phycobiliproteins, and carotenoids. Thus, increasing the FeSO4 concentration to 0.1 g/L has led to the increase in fatty acid individuals, which in turn, resulted in potential enhancement of the biodiesel production from A. platensis. [ABSTRACT FROM AUTHOR]