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Among several emerging technologies that are focused on finding sustainable routes for reforming heavy oils and/or alcohols into valuable fuels and complex chemicals, nonthermal plasma shows promise both due to its non-equilibrium nature and its ability to use intermittent renewable electricity. In this work, we investigate its interaction with organic compounds as a "green" process for simultaneously synthesizing hydrogen, cracking heavy oils, and producing more valuable, complex chemicals. A pin-to-plate microsecond-pulsed argon plasma was used at temperatures of 20, 0, and −20 °C. Using 390 kJ/kg of specific energy input, we were able to achieve a conversion efficiency of 771.4 mmol/kW h for the treatment of the hexane− ethanol mixture at 0 °C. It is concluded that the production of H 2 and other lower fuels (gas hydrocarbons) can be increased by the addition of alcohols in our reforming processes. At 0 °C, the production efficiency and selectivity of gas products were found to be higher compared to other temperatures. A low temperature of −20 °C showed the highest production efficiency for liquid products. Product formation was observed to mainly undergo dissociation and dehydrogenation, whose reaction pathway is also discussed.

One of the most important issues in recent times is the remediation of wastewater discharged from different industries. Several of the growing economies have been investing heavily to reduce the discharged waste content for economic and environmental sustainability. The wastewater when discharged into natural water bodies harms the flora and fauna of the surrounding environment, which in turn disrupts the ecosystem and affects the food chain. It also increases and possesses a variety of health risks to human beings. To eliminate the potential threats, a critical analysis of the past research and upcoming remediation technologies is necessary. Over the years, a lot of advancements have been made to curb the disruption of the natural ecology from effluent discharges by different industries like the leather industry wastewater, Rice mill wastewater, pharmaceutical industry wastewater and Coke Oven wastewater. The common characterization techniques that are employed in all of them are to measure the COD and BOD levels, pH, odor, TSS, organic and inorganic materials. Subsequently, the common technologies that are in use to treat these wastewaters are mainly physicochemical treatments like adsorption, electro-coagulation/flocculation, nanofiltration, Fenton’s oxidation or biological treatments like aerobic/anaerobic microbial degradation. An important requirement is to understand the situation currently prevalent in wastewater treatment to develop better and advanced methods for increased efficiency and waste removal. The aim of this chapter is to give a detailed account on the composition, characterization, and treatment strategies of the discharged effluent to enhance the knowledge of available resources and instigate ideas of future improvements.

Coke oven sectors dispense phenol and cyanide into the circumferential ecosystem, which becomes a serious concern to the subsistence of the flora and fauna. The current study investigates phenol–cyanide treatment using carbon alginate beads immobilized with mixed bacterial consortium. Response surface using central composite design was contrived for the batch and packed bed bio‐column optimization study. The optimal removal conditions obtained in batch study were 89.77% and 82.33% for phenol and cyanide, respectively, with 10‐g/L adsorbent dosage, time 2 hr, and particle diameter 0.3 cm, whereas 87.22% and 90.97% with 22‐cm column height, column diameter 3 cm, 10‐ml/min flow rate, and 1‐hr operation time. The actual exposure time of the pollutants in the bio‐column reactor was calculated to be 22.15 min. Analysis of variance and model statistics predicted a high coefficient of determination for column operation with R2 = .9950 (phenol), R2 = .9976 (cyanide), and p values < .0001 stating significant model. The quantitative estimation of the combined external mass transfer and biodegradation effect was performed to evaluate correlation as (phenol) and (cyanide) with km = 0.052 and km = 0.055 cm/hr, respectively. The surface morphological study was executed by field emission scanning electron microscopy and Brunauer–Emmett–Teller surface area analysis depicting bacterial film development on the porous carbon matrix for effective treatment of binary system.