Safe and clean water is essential for all living beings. Consumption of polluted water which is contaminated with iron may cause serious health implications. Therefore, removal of Fe3+ from wastewater is prerequisite for further uses. The present study intended to prepare activated charcoal (AC) from Borassus flabellifer male flower (BF) for the removal of Fe3+ ions from wastewater in a cost effective way. BFAC was produced based on carbonization method. Surface morphology and elemental composition were investigated by Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy. Additionally surface charge was determined by iodine number and zero point charge calculation. Batch adsorption studies were monitored using UV-visible spectroscopy. The obtain results showed a maximum adsorption at pH 8 with 0.3g adsorbent dosage at 50ppm initial Fe3+ ion concentration for 130 min contact time. The analysis of adsorption isotherm was in good agreement with both Langmuir and Freundlich adsorption isotherms. The Fe3+ removal method was found to be controlled by 1st order kinetics mechanism. However, the production cost was much cheaper and the removal performance was comparatively better than other commercial charcoals. Hence, BFAC could be used as a commercial charcoal in rural area of Bangladesh for purification of waste water.

Microbial-mediated Sb volatilization is a poorly understood part of the Sb biogeochemical cycle. This is mostly due to a lack of laboratory and field-deployable methods that are capable of quantifying low-level emissions of Sb from diffuse sources. In this study, we validated two methods using a H₂O₂ -HNO₃ liquid chemotrap and an activated coconut shell charcoal solid-phase trap, achieving an absolute limit of detection of 4.6 ng and below 2.0 ng Sb, respectively. The activated charcoal solid-phase trapping method, the most easily operated method, was then applied to contaminated shooting range soils. Four treatments were tested: 1) flooded, 2) manure amended + flooded, 3) 70 % water holding capacity, and 4) manure amendment +70 % water holding capacity, since agricultural practices and flooding events may contribute to Sb volatilization. Volatile Sb was only produced from flooded microcosms and manure amendment greatly influenced the onset and amount of volatile Sb produced. The highest amount of volatile Sb produced, up to 62.1 ng kg⁻¹ d⁻¹, was from the flooded manure amended soil. This suggests that anaerobic microorganisms may potentially be drivers of Sb volatilization. Our results show that polluted shooting range soils are a source of volatile Sb under flooded conditions, which may lead to an increase in the mobility of Sb. Some of these volatile Sb species are toxic and genotoxic, highlighting the role of Sb volatilization on environmental health, especially for individuals living in contaminated areas exposed to wetlands or flooded conditions (e.g., rice paddy agriculture surrounding mining areas). This work paves way for research on Sb volatilization in the environment.

Marine oil spill often causes contamination of drinking water sources in coastal areas. As the use of oil dispersants has become one of the main practices in remediation of oil spill, the effect of oil dispersants on the treatment effectiveness remains unexplored. Specifically, little is known on the removal of dispersed oil from contaminated water using conventional adsorbents. This study investigated sorption behavior of three prototype activated charcoals (ACs) of different particle sizes (4–12, 12–20 and 100 mesh) for removal of dispersed oil hydrocarbons, and effects of two model oil dispersants (Corexit EC9500A and Corexit EC9527A). The oil content was measured as n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and total petroleum hydrocarbons (TPHs). Characterization results showed that the smallest AC (PAC100) offered the highest BET surface area of 889 m2/g and pore volume of 0.95 cm3/g (pHPZC = 6.1). Sorption kinetic data revealed that all three ACs can efficiently adsorb Corexit EC9500A and oil dispersed by the two dispersants (DWAO-I and DWAO-II), and the adsorption capacity followed the trend: PAC100 > GAC12 × 20 > GAC4 × 12. Sorption isotherms confirmed PAC100 showed the highest adsorption capacity for dispersed oil in DWAO-I with a Freundlich KF value of 10.90 mg/g∙(L/mg)1/n (n = 1.38). Furthermore, the presence of Corexit EC9500A showed two contrasting effects on the oil sorption, i.e., adsolubilization and solubilization depending on the dispersant concentration. Increasing solution pH from 6.0 to 9.0 and salinity from 2 to 8 wt% showed only modest effect on the sorption. The results are useful for effective treatment of dispersed oil in contaminated water and for understanding roles of oil dispersants.

Good quality activated charcoals were prepared from areca nutshell and coconut shell using phosphoric acid as a chemical activating agent at 400oC. Physico-chemical properties like iodine number, methylene blue number, and surface area of two activated charcoals were measured to assess the porous nature. A special test called acetic acid number was devised to understand the quality of functional groups on charcoal surfaces. Proximate analysis and physical properties of the two activated charcoals closely matched those of a commercial sample, confirming the good quality of samples prepared in the laboratory. Adsorption of isolated caramel from waste stream obeyed Freundlich isotherm, and the data could be explained based on the physisorption of large size molecules on the walls of mesoporous solid surface. Adsorption of methylene blue involving Coulombic attraction towards the areca nut shell-derived activated charcoal could be predicted and confirmed based on the acetic acid number for the first time.

Tannery wastewater contains a significant amount of chemical compounds, including toxic substances. Due to the toxicity and negative environmental effects of these tannery effluents, mandatory treatment is necessary. The main objective of this study was to treat effluent from an artisanal tannery in the city of Fez (Morocco) using the adsorption process with activated charcoal derived from olive pomace. The physicochemical characterization of tanning water included several parameters, such as chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), suspended solids (SS), sulfate ions (SO42-), nitrate, and chromium Cr(VI). The analyses show that the adsorption process reduced nitrate by 57.54%, sulfate by 94.08%, TKN by 74.84%, COD by 68.18%, Cr by 91.27%, and Cr (VI) by 89.78%. The activated charcoal was characterized before and after tannery effluent treatment using various techniques, including FT-IR, SEM, and EDX. From the above, it can be inferred that using activated carbon made from olive pomace has the potential to reduce tannery effluent pollution parameters. This innovative approach demonstrates that competitive results can be achieved without sacrificing economic viability, thereby promoting sustainable practices in the treatment of industrial liquid waste and wastewater treatment plants.