Juan Carlos Asensi

Procedure for checking and fitting experimental liquid-liquid equilibrium data

An objective method was developed to check and fit liquid-liquid equilibrium data obtained experimentally. The analytical concentrations are changed slightly within the interval given by the uncertainties of the determinations in order to satisfy the material balances. The method consists of a minimisation with constraints of a proposed objective function.

Liquid-liquid-solid equilibria for the ternary systems water-lithium chloride-1-propanol or 2-propanol at 25 °C

Liquid-liquid-solid equilibria for the ternary systems water-lithium chloride-1-propanol and water-lithium chloride-2-propanol at 25 °C have been measured experimentally. The equilibrium diagrams determined show differences between the two systems. In the system with 1-propanol, the solid phase of the liquid-liquid-solid region is monohydrated salt. However in the system with 2-propanol it is anhydrous salt.

Modeling eutrophication kinetics in reservoir microcosms

Abstract This study addresses the question of how a general seasonal eutrophication model, WASP5, can handle daily phytoplankton and nutrient dynamics in perturbed microcosms for 1- to 2-week periods of time. It is intended to explore both the interpretative and the predictive capabilities of conventional kinetic formulations. The general method adopted in this study is to first apply EUTRO5, a component of WASP5, to a well-behaved microcosm, calibrating the parameter values and reformulating equations if necessary. Next, the calibrated model is subjected to testing in other microcosm experiments, with altered parameter values if necessary. Model performance is further explored through sensitivity analyses to try to “explain” the observed kinetics in the experiments, and a two-way ANOVA is finally applied to the simulated vs observed evolution curves of the three main variables, i.e. chlorophyll a, soluble-P and ammonia-N in all experiments and microcosms studied.

Quaternary liquid-liquid equilibrium: water-acetic acid-2-butanone-cyclohexane at 25°C

Abstract Mutual solubility and tie line data at 25°C, and atmospheric pressure are presented for the quaternary system wateracetic acid-2-butanonecyclohexane. The system contains two pairs of partly miscible compounds with very different solubilities which produce a solubility surface with a large hump and tie lines which do not lie on tie line planes. The UNIQUAC equation is used to correlate the liquid-liquid equilibrium data.