A mean-field kinetic model was developed to describe a diffusion-controlled bulk cross-linking photopolymerization. This model incorporates all the physical transport limitations that directly or indirectly affect polymerization parameters and rate constants in such reactions. Events such as the continuous decrease in initiator efficiency and the presence of a temporary excess free volume were ...

Biodegradation of phenol in the presence of glucose as a supplementary substrate was investigated with mixed microbial consortium isolated from waste effluent of coke-steel factory. Batch experiments were carried out at room temperature and pH value of 7. Initial phenol and glucose concentrations were in the range of 25-1000 mg/l and 500-3000 mg/l, respectively. In a dual substrates system the ...

Monoaromatic hydrocarbons such as benzene have been found in sludge created by oil production facilities and industries. Benzene is considered as a carcinogenic substrate and biodegradation, primarily under aerobic conditions, is an important environmental process for water and soil associated benzene remediation. Aerococcus sp. strain BPD-6 isolated from petroleum hydrocarbon contaminated oily...

The degradation of wine distillery wastewaters by aerobic biological treatment has been investigated in a batch reactor. The evolution of the chemical oxygen demand, biomass and total contents of polyphenolic and aromatic compounds was followed through each experiment. According to the Contois model, a kinetic expression for the substrate utilization rate is derived, and its biokinetic constant...

A theoretical model of a surface electrode reaction coupled with a preceding chemical reaction (surface CE electrode mechanism) is theoretically studied under conditions of square-wave voltammetry. The position and the shape of the theoretical voltammograms are function of the redox kinetic parameter k 1⁄4 ks f where ks is the standard electron exchange rate constant and f is the frequency of t...

Biological N2 fixation is achieved under ambient conditions by enzymatic catalysis. The enzyme nitrogenase has been studied extensively, but the N2 chemical reduction step is, by far, not rate limiting and hard to examine. A new method was developed that allows studying the reduction transition state within the enzyme's complex kinetic cascade by means of the 15N kinetic isotope effect on the r...

The purpose of this work was to study the effect of initial pH and yeast Saccharomyces Cerevisiae on biogas production from tofu wastewater (TW). The initial pH was varied in ranging of 5 – 9 in substrate without yeast (T5-T9) and with yeast (TY5-TY9). The results showed that optimum initial pH was 8. The maximum biogas was resulted in T8 (275 mL) and TY8 (421 mL). Yeast addition increased tota...

the aim of this paper is to study the kinetic study carbonylation of methanol using of the homogeneous rhodium catalyst and ch3i as the promoter in acid media based on monsanto process. the reaction was carried out in liquid media in the constant pressures 20,28 and 40 atm. and temperatures 170 to185oc, espect to the  initial  reactant concentrations and co pressure.  it was identified that the...

the olefins polymerization process in a slurry reactor is discussed. the reaction rate dynamics was analyzed and the contributions of feed flow, gas-liquid mass transfer, polymerization reaction, and catalyst deactivation were estimated. the propylene solubility in a solvent mixture “heptane” was calculated using soave-redlich-kwong equation of state. these data were then approximated by henry-...