vanadium phosphorus oxides (vpo) has been applied as a heterogeneous catalyst in gas phase oxidation reactions and its application is very limited in liquid phase. in this study a series of cobalt-doped vanadium phosphorus oxides (vpo-co) catalysts with different loading of co (0.01-1.0 mol ratio of co/v) were prepared. oxidation of benzyl alcohol was studied in the liquid phase over vpo and vp...

in this paper, size distribution of nano-bubbles was measured by the reliable and fast method of laserdiffraction technique. nano-bubbles were produced using a nano-bubble generator designed and madebased on hydrodynamic cavitation phenomenon in venturi tubes. a central composite design withresponse surface methodology was used to conduct a five factor, five level factorial experimental designo...

in this present study the dissolved air flotation (daf) system was investigated for the treatment of kermanshah oil refinery wastewater. the effect of three parameters on flotation efficiency including of flow rate (outflow from the flotation tank), saturation pressure and coagulant dosage on chemical oxygen demand (cod) removal was examined experimentally. all the experiments were done under a...

in order to reduce the costs associated with poly-β-hydroxybutyrate production, growth and poly-β-hydroxybutyrate production of ralstonia eutropha were studied in batch culture on different carbon sources. experiments were designed and conducted to not only lower the cost of poly-β-hydroxybutyrate production by using inexpensive substrates, but also to increase poly-β-hydroxybutyrate production...

In the present study Response surface methodology (RSM) was used to investigate the combined effect of relevant process variables to maximize the production of xylanase in submerge fermentation by Penicillium citrinum MTCC 2553. The process variables include pH (6.5, 7.0, and 7.5); temperature (25, 30, and 35°C); agitation speed (190, 200, and 210 rpm); and, substrate (xylan) concentration (0.7...

Lipase-catalyzed production of triethanolamine-based esterquat by esterification of oleic acid (OA) with triethanolamine (TEA) in n-hexane was performed in 2 L stirred-tank reactor. A set of experiments was designed by central composite design to process modeling and statistically evaluate the findings. Five independent process variables, including enzyme amount, reaction time, reaction tempera...

in the present study, the effects of four factors including initial sulfide concentration (mg l-1 ), agitation speed (rpm), amount of inoculums (%) and sodium concentration (mg l-1) on removal efficiency (%r) and yield of sulfate production by thioalkalivibrio versutus from synthetic spent caustic were investigated. for this purpose, experiments are designed by design of experiments (doe) and r...

background: application of potassium ferrate is a chemical oxidation approach used for water and wastewater treatment. the aim of this study is to apply central composite design (ccd) and response surface methodology (rsm) to optimize potassium ferrate consumption in the treatment of wastewater from carpet industries. methods: samples in this experimental study were collected from wastewater, o...

anodic aluminum oxide (aao) fabricated by two step anodization technique, is used as a template to synthesize feco nanowire arrays by ac electrodeposition technique. response surface methodology (rsm) is applied to design the experiments, fit an empirical model and optimize the conditions to achieve the best magnetic properties. the magnetic properties, pore dimensions, composition and structur...

In this work, response surface methodology (RSM) and artificial neural network (ANN) were used to predict the decolorization efficiency of Reactive Red 33 (RR 33) by applying the O3/UV process in a bubble column reactor. The effects of four independent variables including time (20-60 min), superficial gas velocity (0.06-0.18 cm/s), initial concentration of dye (50-150 ppm), and pH (3-11) were i...