Augustine Chioma Affam

Conventional methods and emerging wastewater polishing technologies for palm oil mill effluent treatment: a review.

The Malaysian palm oil industry is a major revenue earner and the country is ranked as one of the largest producers in the world. However, growth of the industry is synonymous with a massive production of agro-industrial wastewater. As an environmental protection and public health concern, the highly polluting palm oil mill effluent (POME) has become a major attention-grabber. Hence, the industry is targeting for POME pollution abatement in order to promote a greener image of palm oil and to achieve sustainability. At present, most palm oil mills have adopted the ponding system for treatment. Due to the successful POME pollution abatement experiences, Malaysia is currently planning to revise the effluent quality standards towards a more stringent discharge limits. Hence, the current trend of POME research focuses on developing tertiary treatment or polishing systems for better effluent management. Biotechnologically-advanced POME tertiary (polishing) technologies as well as other physicochemical methods are gaining much attention as these processes are the key players to push the industry towards the goal of environmental sustainability. There are still ongoing treatment technologies being researched and the outcomes maybe available in a while. However, the research completed so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the new standards. To this end, the most feasible technology could be the combination of advanced biological processes (bioreactor systems) with extended aeration, followed by solids separation prior to discharge. Chemical dosing is favoured only if effluent of higher quality is anticipated.

A review of recent developments in flammability of polymer nanocomposites

Abstract Polymer nanocomposite flame retardancy has become a critical parameter in industrial material application. Recent environmental policies have prohibited the incorporation of halogenated flame-retardant compounds into polymers owing to the high level of environmental degradation caused by high levels of toxic gas and smoke emission. The demand for zero-halogen flame-retardant compounds by both researchers and manufacturers is due to the inherent advantages accruable from their incorporation like very minimal toxic emission, minimal smoke release, zero corrosive gas release, reduced corrosion activities and absence of dripping in fire condition. This has necessitated the quest for eco-compliant replacements for halogenated flame suppressants. Recent insight has shown the eco-compliancy of exfoliated graphene nanoplatelets as flame retardants when incorporated into polymer nanocomposites (PNCs). Relative to the propensity to retard flame, increasing quantities of exfoliated graphene nanoplatelets have exhibited the capability to significantly repress critical flammability parameters like heat release rate (HRR), peak HRR (PHRR), rate of carbon monoxide production, smoke production rate and total mass loss rate while simultaneously increasing limiting oxygen index, time of ignition and total PHRR, thereby retarding flammability and creating better chance to reduce loss and casualty in real-life fire situation through the formation of even layers of carbonaceous char in the condensed phase capable of efficiently suppressing the thermal decomposition caused by oxygen and heat to the polymer matrix and cutting off the flaming path. This paper gives an insight into recent developments in flame retardancy of PNCs, with special emphasis on the flame-retardancy propensity of exfoliated graphite nanoplatelets.

Degradation of Pesticide Chlorothalonil by Visible Light-Responsive Photocatalyst Ferrioxalate and under Solar Irradiation

Ferrioxalate is a visible light-responsive photocatalyst. The solar ferrioxalate/ process has high degradation efficiency because ferrioxalate is able to absorb light strongly at longer wavelength and generates hydroxyl radical with high quantum yield. Degradation of pesticide chlorothalonil in aqueous solution by ferrioxalate/ under solar irradiation was examined. The optimum operating conditions for treatment of a 300 mg/L chlorothalonil aqueous solution were obtained by using the central composite design of the response surface methodology. Under the optimum operating conditions (/COD molar ratio 2.75, /Fe3

Treatment of aqueous solution of antibiotics amoxicillin and cloxacillin by modified photo-Fenton process

AbstractThe study examined the effectiveness of the modified photo-Fenton (UV-vis/ferrioxalate/H2O2) process in treatment of an antibiotic aqueous solution. The optimum operating conditions for the treatment of a 300 mg/L antibiotic aqueous solution (150 mg/L of amoxicillin and 150 mg/L of cloxacillin) were obtained by using the central composite design of the response surface methodology. Under the optimum operating conditions (H2O2/chemical oxygen demand (COD) molar ratio 2.75, H2O2/Fe3+ molar ratio 75, H2O2/C2H2O4 molar ratio 37.5, reaction time 90 min and pH 3), 78.37, 45.94, and 52.30% removal of COD, NH3–N, and TOC, respectively, were achieved and the biodegradability (biochemical oxygen demand(BOD)5/COD ratio) improved from 0 to 0.35. Model prediction and experimental removal efficiency were in agreement with < 5% error. The modified photo-Fenton process is effective in pretreatment of the antibiotic aqueous solution for biological treatment.