Showing papers in "Chemical Engineering Science in 1988"

TL;DR: In this paper, the kinetics of low-pressure methanol synthesis, starting from CO, CO2 and hydrogen over a commercial Cu-Zn-Al catalyst, were studied in a spinning basket reactor at p = 15-50 bar and T = 210-245°C.

TL;DR: In this paper, the operating conditions needed to inhibit carbon deposition and nickel carbide formation as well as study the possible solid-state reactions within the catalysts in reforming methane with CO2.

TL;DR: In this paper, the rate of absorption of CO 2 into aqueous solutions of KOH, NaOH and LiOH containing neutral electrolytes (carbonates, chlorides, bromides, nitrates and sulphates) have been performed using the laminar-jet technique.

TL;DR: In this article, the influence of small amounts of impurities (amines) on the measured mass transfer rates of CO2 and primary and secondary alkanolamines (DEA and DIPA) was investigated.

TL;DR: In this article, the problem of determining whether there exist rate constants for a deficiency one network such that the corresponding isothermal mass action differential equations admit multiple positive steady states is considered.

TL;DR: In this paper, an energy balance over an air-lifts loop is used to obtain a theoretical equation for the prediction of liquid circulation velocity in those devices and the resulting equation is shown to satisfactorily describe most of the available liquid circulation data (13 different air-lift reactors) for a large range of reactor operating scales (0.06-1.06 m3 liquid volumes) including measurements on two pilot scale vessels.

TL;DR: In this paper, the reaction between CO2 and tertiary alkanolamines (MDEA, DMMEA, TREA) has been studied in aqueous solutions at various temperatures.

TL;DR: In this paper, a simple and efficient method for solving the population balance equation in crystallization in the most general case: unsteady state, size dependant growth rate, agglomeration or breakage of crystals.

TL;DR: A simple method for predicting the formation of gas hydrates is described in this paper, where the influence of inhibitors like alcohols, glycols or salts on the hydrate formation is accounted for by a very flexible and robust program based on the method.

TL;DR: In this paper, a thermodynamic treatment is developed wherein the surface concentration of ionic surfactants is distinguished from their surface excess concentration by the contribution from the electrical double layer.

TL;DR: In this article, a set of transformed composition variables is introduced to simplify the design equations for single-feed, multicomponent reactive distillation columns, and a general method of calculating minimum reflux ratios for reactive distilled columns is presented.

TL;DR: In this paper, the influence of the operating parameters upon the shape of the temperature profiles in the stationary state als as well as the stability of the ignited state are studied by model calculations.

TL;DR: In this paper, the equations describing simple distillation of homogeneous reactive mixtures are derived, and residue curve maps are computed for ideal and non-ideal systems, showing that by allowing the components of a liquid mixture to react, we can either create or eliminate distillation boundaries.

TL;DR: In this article, it was shown that under certain conditions partially wetted surfaces yield practically the same drying rate as entirely wetted ones, and that less than 1% of the surface needed to be activated in order to give the same reaction rate such as an entirely activated one.

TL;DR: In this article, a new criterion for parametric sensitivity or thermal runaway is proposed in the context of thermal explosions, which can also be readily utilized for chemical reactors, and it is based on the rigorous concept of normalized sensitivity.

TL;DR: In this paper, the intrinsic rate equations for steam-methane reforming (RF) and shift (SF) reaction were determined by the calculation of mass and heat balances considering interphase and intraphase diffusions using a numerical solution of the non-linear two-point boundary value problem.

TL;DR: In this paper, the Young-Laplace equation does not predict the known instability of collars forming lenses, but a simple approximation that does is proposed, which gives a critical film thickness of 0.12 R T * which demarks the transition between films that evolve into stable collars and those that break up to form lenses.

TL;DR: In this article, the conditions for formation of reactive-azeotropes in constant-volatility systems are derived, and it is shown that reactive amazotropes can occur only when the volatilities of the reactants are either all higher or all lower than those of the products.

TL;DR: In this article, the hydrodynamical characteristics of the flow induced by a six flat blades disk turbine were determined by laser Doppler anemometry using two cylindrical tanks, geometrically similar, with a flat bottom and four vertical baffles.

TL;DR: In this paper, a realistic study of the LV-control of a high-purity distillation column is presented, where linear controllers designed based on a linearized model of the plant are found to yield acceptable performance also when there is model mismatch.

TL;DR: In this article, the authors proposed a method of predicting the kinematic viscosity of a liquid-phase mixture from the known viscosities of the pure components based on Eyring's theory.

TL;DR: In this article, the Darcy-scale phenomenological coefficients governing the macroscopic transport of a reactive solute within a spatially periodic model of a porous medium are studied analytically for the case where the solute undergoes a generally inhomogeneous first-order irreversible chemical reaction in the interstitial fluid region and/or on the surfaces of the bed particles.

TL;DR: In this paper, the authors studied the transverse heat transfer characteristics of a fully developed forced convective flow in a variable-porosity packed bed bounded between parallel plates, separated at a distance 2 H * and heated asymmetrically.

TL;DR: In this paper, the authors described a theoretical and experimental study of the mechanisms by which plunging jets entrain air followed other workers, it is proposed that the mechanism of air entrainment undergoes a qualitative change as the jet impact velocity (U i ) is increased.

TL;DR: In this article, the influence of mass transfer for two liquid-phase hydrogenation reactions has been studied in a monolithic catalyst reactor and the enhanced mass transfer between phases was due to very high interfacial surface area in combination with a short diffusion length.

TL;DR: In this article, an analysis of the particle trajectories (flows) provides a rational way to create chaotic (or good) mixing, and the authors suggest new experiments for discriminating between possible mechanisms and routes to complex or turbulent behavior.

TL;DR: In this paper, the applicability of the ideal adsorbed solution (IAS) theory was tested for multicomponent adsorption equilibria of organic components from aqueous solutions on activated carbons.

TL;DR: In this article, the authors outline how risk assessment can be performed by extending Chemical Engineering Principles to the study of potential runaway reactions, where processes with intrinsically low risks can be designed based on predictions of their response to failure modes.

TL;DR: In this paper, the kinetics of the three-phase methanol synthesis, starting from carbon monoxide, carbon dioxide and hydrogen over a commercial Cu-Zn-Al catalyst suspended in squalane as the slurry liquid, were studied in a well-mixed, agitated slurry reactor at p = 15 − 40 bar and T = 210 − 260 °C.

TL;DR: In this paper, the reduction and subsequent sulfidation of single cylindrical pellets of ZnFe2O4 have been studied in a microbalance reactor and the time-conversion results during sulfidation are consistent with the unreacted core model assuming the global kinetics are controlled by mass transfer and pore diffusion.