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Gallic acid is an important carboxylic acid used in pharmaceutical industries owing to its medicinal properties. The separation of gallic acid from fermentation broth and dilute aqueous streams is a challenging task. Therefore, in the present study the reactive extraction of gallic acid from an aqueous solution by using tributyl phosphate in octanol, ethyl acetate, n-hexane, and toluene as diluents, respectively, has been carried out at constant temperature (303 ± 1 K). The results were compared with those of the extraction using pure diluents in order to compute the intensification of extraction obtained. Experiments were performed to investigate the effect of initial acid concentration, extractant concentration, and diluent type. TBP + hexane was found to be most suitable solvent system resulting in the highest distribution coefficient (K D = 24) when TBP was employed at a concentration of 1.516 mol•kg −1 . The equilibrium complexation constant (K E ) was observed to be in the ranges of 3.18−8.8 for n-hexane, 0.91−4.54 for toluene, 2.295−4.546 for ethyl acetate, and 3.57−6.17 for octanol.

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During an oil and gas well drilling the drilling fluids are pumped through the drill string to cool and lubricate the drill bit. This also serves the purpose of bringing the rock cutting back to surface and serves various other purposes also like pressure control and maintain well bore stability. As the well is drilled the casing are lowed from the well from caving in. This results in a situation where there is an annular flow of drilling fluid where the inner pipe is rotating while the outer pipe is stationary. The understanding of fluid dynamics of such situation is extremely important and detailed investigations are required. Though experimental investigation will reflect the actual behavior but with the advancement is the numerical techniques such experimentation can be avoided with the application of computational fluid dynamics. Therefore, the present study employs the homogeneous model to simulate a single-phase fluid flow and predict pressure loss variation in eccentric vertical annuli as a function of varying drilling parameters: fluid velocity, inner pipe rotation speed

Wastewater generated from the coking processes has high load of organic as well as inorganic pollutants which requires the application of effective treatment techniques. In the present work, treatment of coking wastewater (CWW) through catalytic thermolysis has been carried out in batch mode with varying parameters such as type of catalyst, catalyst mass loading, pH, temperature and time. This process was followed by adsorption as second stage treatment process. The final parameters obtained are as Chemical Oxygen Demand (COD) 20 mg/L, cyanide 0.42 mg/L and nil amount of phenol from the high initial organic and inorganic load. The study aims reduction of COD, phenol, and cyanide content in the wastewater to the permissible limits. The mechanism and kinetics of thermolysis process have been also presented in this study.