Optimization of the simultaneous chemical and biological mineralization of perchloroethylene (PCE) by modified Fenton's reagent and Xanthobacter flavus was investigated by using a central composite rotatable experimental design. Concentrations of PCE, hydrogen peroxide, and ferrous iron and the microbial cell number were set as variables. Percent mineralization of PCE to CO2 was investigated as...

Lead biosorption by Klebsiella sp. 3S1 isolated from a wastewater treatment plant was investigated through a Rotatable Central Composite Experimental Design. The optimisation study indicated the following optimal values of operating variables: 0.4 g/L of biosorbent dosage, pH 5, and 34°C. According to the results of the kinetic studies, the biosorption process can be described by a two-step pro...

Wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. In this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., Lipozyme(®) RMIM (Rhizomucor miehei) and Novozym(®) 435 (Candida antarctica). Response surface methodo...

The objective of this study was to optimise the extraction conditions for phenolic compounds from neem (Azadirachta indica) leaves using response surface methodology (RSM). A central composite rotatable design (CCRD) was applied to determine the effects of acetone concentration (%), extraction time (mins), and extraction temperature (oC) on total phenolic content (TPC) from neem (Azadirachta in...

Response surface methodology (RSM) was used to optimize the microwave-assisted direct liquefaction of Sargassum polycystum C.Agardh in ethylene glycol (EG) with H(2)SO(4) as a catalyst. Based on the results of single factor experiments, EG-to-feedstock ratio, temperature and catalyst content were chosen as independent variables for a central composite rotatable design (CCRD). The optimal liquef...

The Passiflora cincinnata Mast. has high flavor and potential for wine other alcoholic beverages production. However, production, the presence of pectin becomes undesirable, as it influences efficiency fermentation process clarity final product. objective this study was to optimize hydrolysis in Caatinga passion fruit must production with pectinolytic enzymes, using a Central Composite Rotatabl...

In the present work, attempts have been made to optimize EDM process with an aspect of surface modification AISI P20+Ni die steel using powder metallurgy (P/M) electrode. Experiments performed according central composite rotatable (CCD) design response methodology (RSM). Effects compaction pressure (Cp), peak current (Ip), pulse-on time (Ton), and duty cycle (τ) were correlated roughness (SR) m...

A response surface methodology (RSM) has been utilized for investigating the effects of speed shelling, melon seed moisture content and number beaters a developed mechanized centrifugal shelling cleaning machine. The machine shells then cleans shelled from other impurities. experiment was based on central composite rotatable design (CCRD). results experiments revealed that highest efficiency 88...