In slurry bubble column reactors, catalyst particles may adhere to gas bubbles. Thus, mass transfer limited reactions can be significantly improved either by increasing G-L mass transfer coefficient kL or specific surface area a. The scope of this work is to study the influence of model parameters on coalescence and G-L mass transfer, in order to develop new rules for design and scale-up of slu...

OBJECTIVE To investigate the performance of soil-slurry bioreactor used for remediating contaminated soil with 4-nitrophenol (4-NP). METHODS The slurry bioreactor was used to degrade different concentrations of 4-nitrophenol with or without inoculating the acclimated activated sludge. HPLC system (Hewlett-Packard model 5050 with a UV detector) was used for the quantification of 4-nitrophenol....

Modelling anaerobic digestion processes is a key aspect of studying and optimizing digesters and related waste streams. However, for the satisfactory prediction of biogas production and effluent characteristics, some parameters have to be calibrated according to the characteristics of the substrates. This article describes a calibration procedure for the IWA 'Anaerobic Digestion Model no. 1' ap...

This study reports the analysis and design of a liquid phase esterification process to convert acetic acid with isoamyl alcohol into acetate via reactive pervaporation, in presence an Amberlite IR-120 ion exchange resin catalyst. To accomplish this, catalytic reactor is coupled separation membrane unit (Pervaporation Membrane Reactor (PVMR)). In proposed unit, chemical reaction equilibrium favo...

A semicontinuous slurry-microcosm method was applied to mimic trichloroethylene (TCE) cometabolic biodegradation field results at the Que-Jen in-situ pilot study. The microcosm study confirmed the process of aerobic cometabolism of TCE using toluene as the primary substrate. Based on the nucleotide sequence of 16S rRNA genes, the toluene-oxidizing bacteria in microcosms were identified, i.e. Ra...

background: among alkanes, n-alkanes with medium chain have been identified as the most important contaminants of the soil. n-hexadecane (c16h34) with low solubility in water also belongs to this group and has been used by many researchers as a model contaminant. the present study aimed to investigate the effect of the external source of carbon (glucose) as co-substrate on removal of hexadecane...

We report the semicontinuous, direct (anaerobic sequencing batch reactor operation) hydrogen fermentation of de-oiled jatropha waste (DJW). The effect of hydraulic retention time (HRT) was studied and results show that the stable and peak hydrogen production rate of 1.48 L/L ∗ d and hydrogen yield of 8.7 mL H2/g volatile solid added were attained when the reactor was operated at HRT 2 days (d) ...

Anaerobic digestion of source-separated municipal organic waste is considered feasible in Denmark. The limited hydraulic retention in the biogas reactor (typically 15 d) does not allow full degradation of the organic waste. Storage of anaerobically digested municipal organic waste can therefore be a source of methane (CH4) emission that may contribute significantly to the potential global warmi...

This article presents the research results on production and performance of palladium-only catalytic converters. Monolith is used as the catalyst carrier and gamma alumina as the substrate. Dipping method is used for monolith washcoating. Palladium as the active metal is impregnated on gamma alumina using wet impregnation to produce catalyst samples. The effects of factors such as percent solid...

In the present study, a heterogeneous and homogeneous gas flow dispersion model for simulation and optimization of a large-scale catalytic slurry reactor for the direct synthesis of dimethyl ether (DME) from synthesis gas (syngas) and CO2, using a churn-turbulent regime was developed. In the heterogeneous flow model, the gas phase was distributed into two bubble phases including small and large...