Affinity chromatography or affinity adsorption is an effective isolation or purification operation based on biospecific interaction, that is, biological recognition. Operations for preparative purposes have recently been utilized as a potential means of downstream processing in bioproduct manufacturing processes. For affinity chromatography and biospecific adsorption, adsorption systems of a mobile phase and a stationary adsorbent phase, the theories of mass transport between phases, the operation steps of adsorption and elution, and practical application in bio-industries are described. Other biospecific separations such as affinity partition and affinity precipitation are also described.
Multistage relaxation methods are proposed for solving nonideal multicomponent distillation problems involving multiple feeds and side-cut streams. In the present work, two-stage and three-stage relaxation algorithms are developed from a single-stage relaxation algorithm with simultaneous correction of liquid composition and temperature. From a feasibility study using numerical examples, the two-stage relaxation method is recommended since the effect of the formulation complexity on the improvement of convergence is higher than that of the three-stage method.
An experimental investigation of the adsorption properties of metal ions onto gel was carried out by using hydrolyzed polyacrylamide gel and copper sulphate, ferrous ammonium sulphate and ferrous sulphate solutions. Considering that carboxyl groups in the gel bond with the metal ions according to their electric charge number, the adsorption properties were examined on the basis of dissociation equilibriums from monocarboxyl to dicarboxyl acid. From theoretical analyses, empirical equations that give the amount of metal ions adsorbed on the gel were obtained. For the adsorption equilibrium of copper and ferrous ions, the amount of ions adsorbed within the gel can be calculated well from the initial and equilibrium concentrations of the metal ions in aqueous phase, the concentrations of hydrogen ions, the weight of the gel and the volume of solution used.
Experiments were performed to investigate the gas–liquid interfacial area and the liquid-phase mass transfer coefficient of a two-phase dispersion on sieve plates with hole diameters of 4–12 mm and with free areas of 5.5–50.4% without downcomer. Operation was carried out at high gas velocities using cobalt-catalyzed oxidation of aqueous sodium sulfite solution with air. The two-phase dispersion showed froth regime and transition regime, which is called partially developed spray regimes/mixed froth regimes, depending on the gas velocities. The gas–liquid interfacial area of the two-phase dispersion in the froth regime is influenced by the free area of the plate, whereas no effect of free area is found in the transition regime. The correlations of interfacial area for each regime are given on the basis of the correlation obtained by Zuiderweg under a gas–liquid cross-current condition. Empirical equations for the Sherwood number based on liquid depth are obtained. Using the results of the interfacial area and the mass transfer coefficient, the mass transfer volumetric coefficient can be predicted.
For CZ crystal growth of an oxide (Al2O5), finite element analyses of the thermal stress field in the crystal are carried out, and the effect of interface shape on the maximum shear stress in the crystal is investigated. When the crystal rotation rate increases, with other operating conditions unchanged, the melt/crystal interface changes its shape from convex to concave toward the melt at the critical Reynolds number (Res*). When Res < Res*, the maximum value of the thermal stress on the interface is insensible to Res and its radial profile is an inversed W-shape. When Res exceeds Res*, however, thermal stress on the interface increases very rapidly and its radial profile becomes W-shaped.
The emulsion polymerization of styrene in a continuous-loop tubular reactor (CLTR) is studied as functions of the soap concentration and temperature. The soap concentrations of sodium lauryl sulfate (SLS) ranged from 3.73 to 24.24 g/l-water, and reaction temperatures ranged from 50 to 70°C are examined. The effects of temperature and soap concentration on the conversion, average diameter of particles, number concentration of particles and average molecular weight are discussed. It is found that instability of monomer conversion and the number concentration of particles during the polymerization are the overshoot but not oscillation or multiple steady states. The phenomenon of monomer conversion is eliminated by adjusting the soap concentration. The reaction mechanism of the polymerization in the case of low soap concentration (3.73 g SLS/l-water) is different from that with a soap concentration higher than 12.40 g SLS/l-water.
A kinetics study of biological phosphorus release/uptake in biomass under anaerobic/aerobic (A/O) condition was made in a laboratory sequential batch reactor (SBR) system. The ratios of P/BOD and TN/BOD of influent feed solution for increasing the intracellular phosphorus must be greater than about 0.01 and 0.13 in this system. Phosphorus uptake was correlated to the uptake of K+ and Mg2+ as ΔK/ΔP = 0.28, ΔMg/ΔP = 0.36 by molar ratios. The rate of phosphorus release for endogeneous respiration of the biomass under anaerobic condition can be described by using a Monod-type equation with respect to phosphorus content in the biomass, and the values of the rate constant, Krp, and the saturation constant, Kkp, are 1.1 × 10–3 h–1 and 1.4 × 10–3 kg/kg respectively. The rate of luxurious phosphorus uptake at the aerobic stage can be expressed by a first-order kinetic equation based on Pxm–Px with the rate constant, Ku, is 0.017 h–1.
A three-phase fluidized bed bioreactor was employed for a biological treatment process of phenolic wastewater. The characteristics of simultaneous utilization of oxygen and substrate (phenol) in the bioreactor were evaluated. In the experiments, activated carbon BAC and CB ball were utilized as media. Air was used for aeration. The model discussed in this paper includes the following steps: (1) Gas–liquid mass transfer of oxygen (2) Liquid–biofilm interfacial mass transfer of oxygen and substrate (3) Intrabiofilm mass transfer and simultaneous biological reaction of oxygen and substrate Two cases, biological substrate removal as rate-determining step and oxygen absorption as rate-defermining step, were evaluated. Within the range of experimental conditions studied, biooxidation of phenol was simply evaluated by treating substrate utilization as zero-order reaction. The experimental results of phenol removal were well explained by an equation based on the assumption of oxygen absorption as the rate-determining step. It was found that biological reaction did not act as the rate-determining step in the case of superficial air velocity up to 1.0 cm/s. The volumetric phenol removal rate becomes more than 8 kg-phenol/(m3-bed·d) by increase of oxygen supply in the three-phase fluidized bed bioreactor.
The extraction of rare-earth nitrates was studied, using tri-n-octylmethylammonium nitrate in xylene as an extractant and ammonium nitrate as a salting-out agent. The capability of this extractant decreases continuously with atomic number apart from a slight increase from Gd to Tb. An extraction scheme occurring for all elements is presented. In this it is assumed that extraction occurs via reaction with monomer, R, of the extractant and the successive stage-wise formation of two extracts, Ln(NO3)3·5R and (Ln(NO3)3)2·5R. The fraction of 1:5 complex is very close to 1 at low loadings, whilst for all elements the fraction of 2:5 complex increases with increased loading. The formation of 1:5 complex is most favored with La and less favored with elements of higher atomic number. The inherent limitation of this extraction system for separation into individual elements is also discussed.
Measurements were made of the effect of interaction between two drops on the simultaneous evaporation of two coaxially arranged water and hexane drops for RePA = 64–230, Sc = 0.59–1.57, DB/DA = 0.54–1.58, L/DA = 0.98–11.04 and BM = 0.02–0.64. The observed diffusion fluxes for water drops were compared with the previous numerical solutions. A systematic deviation from the previous numerical solution under low mass flux conditions was observed for hexane drops. New correlations for the diffusion fluxes of two adjacent drops were proposed by considering the effect of the interaction between two drops, of high mass flux and of variable properties.
Extraction rates of palladium(II) with 2-hydroxy-5-nonyl acetophenone oxime were measured by use of a Lewis-type cell to elucidate the extraction mechanism. It was found that the rate of complex formation both at the interface and in the aqueous phase was determined by the 1:1 complex formation between trihalo complex of palladium, PdX3(H2O)– and the neutral species of β-hydroxyoxime, HR. The extraction rate of the bromo complex of palladium was faster than that of the chloro complex. The rate constants for the complex formation obtained from the extraction rate were compatible with those obtained in an 80 wt% ethanol–water mixture.
Inhaled submicron particles readily penetrate into alveolar regions of the human lung, where the behavior of these particles is largely influenced by mixing between inhaled air and residual air. In the present work, an experimental technique to study mixing and deposition of Brownian particles in an expanding/contracting balloon as a model alveolus was developed by employing a “wash-out” experimental technique. Further, applying a simple number balance equation of particles, the mixing volume and deposition coefficient during a breath were obtained. It was found that (i) there exists a critical value in the duration of balloon expansion/contraction over which Brownian diffusion of aerosol enhances mixing between aerosol and clean air, and the critical duration of balloon expansion/contraction is longer for a larger expansion/contraction volume of the balloon; and (ii) at the same expansion/contraction volume of the balloon, the deposition coefficient per breath is larger for a larger expansion/contraction volume.
For the isothermal desorption of film, the diffusion equation for a slab based on the dissolved solid coordinate is soled numerically with various types of concentration dependence of the diffusion coefficient. Based on the assumption of concentration distribution similarity, the relations between desorption rate and integral average diffusion cuefficient are derived as functions of the ratios of average concentration to center concentration for both the penetration period and the regular regime, regardless of the type of concentration dependence of the diffusion coefficient. By means of these relations, Methods of calculating the diffusion coefficient as a function of solvent concentration are presented for both the initial rate in the penetration period and the rate in the regular regime, which covers the whole concentration range included in the desorption data. The method is usable within an error of 10% in the range of 0.5 < (the ratio of average concentration to center concentration) < 0.9, which covers a variety of concentration dependences of the diffusion coefficient.
A stochastic model to explain the mixing of solid particles in a horizontal agitated vessel with paddle-blades on double parallel axes was proposed. It was first found that the particles are mainly mixed not in the particle beds, but in the spacious part above the beds. On the basis of the experimental findings, the axial mixing process was modeled by using the transient probability of the particles, which was derived from the measured probability of the axial velocity. Predictions by the stochastic model were in good agreement with measurements of particle concentration in the dispersion experiments of Tenda et al.10)
Flow behavior of downflow bubble columns with gas entrainment by a liquid jet operating at high throughputs was investigated in an air–water system. With increasing liquid throughput above the churn-turbulent flow regime, stable downward bubbling flow without bubble coalescence was again obtained. Gas holdup and gas entrainment rate under bubbling downflow conditions were measured and their dependencies on operational conditions were clarified empirically. Experimental equations were proposed to estimate gas holdup and gas entrainment rate. Performance of gas supply was evaluated in terms of energy efficiency and compared with that of other gas-liquid aerators. The evaluation showed that the gas-entraining capacity of this apparatus is sufficient and that its energy efficiency for gas supply is high.
Isobaric vapor–liquid equilibria for binary mixtures of methyl propanoate with ethanol and propan-1-ol are obtained by using a small-capacity recirculating still at 114.66 and 127.99 kPa. In the thermodynamic treatment of the data, the vapor phase is considered nonideal and all systems show positive deviations of ideality. Predictions carried out by using group contribution methods UNIFAC and ASOG are in good agreement with the experimental results, with errors less than 7% in all cases.
Ion exchange resin tablets (7 mm diameter × 7 mm length) were molded from ion exchange resin beads and polyethylene powder in a furnace. 700 ml of the tablets was packed in a Pyrex glass tube of 36 mm diameter as a reaction zone and an Oldershaw column of 30 plates and 32 mm in diameter was employed as the recovery zone of the column. A mixture of methyl acetate and methanol (75:25 by weight) was fed to the bottom of the reaction zone at a rate of 89 g/h and water was fed to the top of the column at a rate of 89 g/h. When all the condensed top vapor was recycled at a rate of 254 g/h, the concentration of methyl acetate in the resulting reaction mixture discharged from the bottom was practically negligible. The reactive distillation column can be incorporated into the process of hydrolysis of methyl acetate for recovery of acetic acid and methyl alcohol. The advantages of the new process are the elimination of two columns in the conventional process and reduction of the heat requirement of the total process. The decrease in heat requirement is estimated to be about 50% that of the conventional process.
The effect of the anionic surfactant sodium dioleylsulfosuccinate on the extraction rate of copper with E-2-hydroxy-5-nonylbenzophenoneoxime in n-heptane was studied. The extraction rate of copper was remarkably enhanced by the addition of the anionic surfactant under appropriate conditions and it was found that the electrostatic interaction between copper and the anionic surfactant and the binding between the extractant and surfactant in the interfacial zone played an important role in the extraction kinetics of copper with the extractant. An extraction mechanism of copper with E-2-hydroxy-5-nonylbenzophenoneoxime in the presence of the surfactant was proposed.