Rate laws continued inhibition

When a solid metal is attacked by oxygen gas, the product of the reaction is the metal oxide which, if it is not volatile, builds up as a surface layer on the metal. The oxide layer may be protective or non-protective. A non-protective layer does not inhibit the continued access of oxygen to the unchanged metal the rate of growth of such an oxide layer is independent of its thickness X and the law of growth is AX/At =. On integration this gives the linear law... 

The dynamic model presented herein builds on that reported previously (I) by incorporating the interactions between volatile acids, pH, alkalinity, gas production rate, and gas composition. The model is developed from material balances on the biological, liquid, and gas phases of a continuous-flow, complete mixing reactor. Appropriate relationships such as yield constants, an inhibition function, Henry s law, charge balances, and ionization equilibria are used to express the interactions between variables. The inputs and outputs for the reactor and the reactions considered are illustrated in Figure 2. 

The rate expression for Fiseher-Tropseh (FT) synthesis has been obtained using a 25 wt.% C0/AI2O3 eatalyst in a 1 liter continuously stirred tank reactor (CSTR) operated at 493K, 1.99 MPa (19.7 atm), H2/CO feed ratios of 1.0-2.4 with varying space velocities to produce 14-63% CO eonversion. Adjusting the ratios of inert gas and added water permitted the impact of added water to be made at the same total flow rate and H2 and CO partial pressures. The addition of water at low levels during FT sjmthesis did not impact CO conversion but at higher levels it decreased CO conversion relative to the same conditions without water addition. The catalytic activity recovered after water addition was terminated. The temporary reversible decline in CO conversion when water was added may be due to the kinetic effect of water by inhibition of CO and/or H2 adsorption. The data of this study are fitted fairly well by a simple power law expression of the form ... 

But due to flotation (bubble-film extraction), the products of bacterial metabolism and the products of bacterial degradation together with other water contaminants are ranoved continuously from recirculation flow through the bubble-film extractor. As a result, another positive feedback is realized in filtration-flotation system. The essence of this effect lies in the inhibition of vital functions of bacteria with increasing microbial metabolite concentration according to the law of chemical kinetics. And in accordance with the same law, bacterial activity is increased as the products of bacterial metabolism are removed from treated water [20]. Thus, we are able to add one more component, namely, AK, to the magnitude (/fj + AK2). The component AK represents the increase in biofiltration efficiency due to bacterial inhibitors removed by means of bubble-film extraction. In such a way, the resulting rate constant of the process takes the form ( fi + AK2 + AKi). 

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