The Influence of Biofilm on the Effectiveness of Ion Exchange Process

Abstract

The ion exchange of ammonia in a synthetic zeolite has been investigated in the presence of Biofilm of nitrifying bacteria. The Biofilm has been cultivated on the zeolite carrier under different hydrodynamic conditions in a plug flow reactor and in a fluidized bed reactor. Samples of the carrier covered by Biofilm have been withdrawn from the reactors and packed into a miniature ion exchange column that has been used to analyze the ion exchange characteristics, i.e., to determine ion exchange equilibria and the mass transport kinetics. For this purpose, the breakthrough curves have been registered at different ammonia loadings and different concentrations of sodium bicarbonate in the solution. To analyze the mass transport mechanism and quantify kinetic coefficients, we have exploited a linear driving force model (i.e., the LDF model) and the generalized model. The ion exchange and mass transfer characteristics of the Biofilm-covered carrier have been compared to those of the virgin zeolite. The effect of Biofilm on the mass transfer kinetics and ion exchange capacity was found to be induced by swelling properties of zeolite.

Coupling Ion Exchange and Biosorption for Copper(II) Removal From Wastewaters

“…The data obtained were approximated by a linear dependence which was exploited to evaluate values of the mass transport coefficients. The contribution of the pore diffusion to the overall mass transport mechanism was evaluated to be negligible compared to that of the surface diffusion (details of this procedure can be found elsewhere 39 ).…”

“…The linear driving force model (LDF) consists of two following equations normalε t ∂ C i ∂ t + ( 1 − normalε t ) ∂ q i ∂ t = normalε e D L ∂ 2 C i ∂ x 2 − u ∂ C i ∂ x ∂ q i ∂ t = k m , i false( q i ACS:no-reduce * − q i false) where C [mol/L] is the concentration in the mobile phase; q , q * [mol/L solid ] are the solid phase concentration and the equilibrium solid phase concentration, respectively; x [m], t [s] are the axial and time coordinates, respectively; u [m/s] is the superficial velocity; D L [m 2 /s] is the dispersion coefficient; ε t , ε e [-] are the total and external, porosity, respectively, k m [1/s] is the overall mass transport coefficient, which lumps the contribution of the internal and external mass transport resistances. For nonlinear isotherms and self-sharpening fronts k m can be expressed as − 1 k …”

Optimization of Quantitative Analysis of Biofilm Cell from Pipe Materials

“…Detaching the biofilm from the surface of the tested installation material is the most complicated step in the entire process. For this purpose, the following physical methods can be used, i.e., sonication of materials with a formed biofilm [10,33,40], removing the biofilm with a sterile cotton swab, scraper or knife [6,34,39,[41][42][43], shaking with the use of glass beads [16] or centrifuged [44]. However, there are still many doubts as to which of the mentioned methods most effectively separates biofilm from the porous structure of materials.…”

Evaluation of Immobilization of Selected Peat-Isolated Yeast Strains of the Species Candida albicans and Candida subhashii on the Surface of Artificial Support Materials Used for Biotrickling Filtration

“…Cultivation of the microorganisms occurs both in interstitial spaces as well as in micropores, the size of which allows penetration of the cells of microorganisms forming so-called sites protected from the impact of adverse shearing forces due to water flow. The biofilter's packing material can play the role of not only a support material for biological film development but also an adsorbent, an ion exchanger, a nutrient medium and a substance buffering the biochemical reaction environment [22]. Apart from the effectiveness of microorganism colonization, the price should also be taken into account while selecting the biofilter's packing.…”