Vicente Gomis

Application of factor analysis to the hydrogeochemical study of a coastal aquifer

Abstract The use of numerical values for the chemical components of waters from an aquifer as input data for factor analysis is shown to be sometimes more convenient than the use of the logarithms of these figures. Factor analysis was applied to the hydrogeochemical study of a coastal aquifer located in Javea, Alicante (Spain). A set of factors was found which explained the source of the ions in the water and even certain chemical processes which accompany the intrusion of seawater, such as the strong adsorption of K on clay minerals.

Liquid-liquid-solid equilibria for the ternary systems water-sodium chloride or potassium chloride-1-propanol or 2-propanol

Abstract Gomis V., Ruiz F., De Vera G., Lopez E. and Saquete M.D., 1994. Liquid-liquid-solid equilibria for the ternary systems water-sodium chloride or potassium chloride-1-propanol or 2-propanol. Fluid Phase Equilibria, 98:141-147. Liquid-liquid-solid equilibria for the ternary systems water-sodium chloride-1-propanol, water-potassium chloride-1-propanol, water-sodium chloride-2-propanol and water-potassium chloride-2-propanol have been measured at 25°C. The salt effect on the water miscible organic compound is greater with NaCl than with KC1, and greater on the 1-propanol than on the 2-propanol.

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.

Application of a model for simulating transport of reactive multispecies components to the study of the hydrochemistry of salt water intrusions

A model for simulating transport of reactive multispecies components has been applied to simulate the chemical changes occurring during salt water intrusion in a confined aquifer. One-dimensional reactive flow in permeable media is simulated by means of a numerical method which assumes local thermodynamic equilibrium. The method uses a set of partial differential equations, based on the conservation of mass, applied to each one of the chemical elements of the system (instead of applying them to the chemical species). In this way, the solution of the problem is simpler since the term which takes into account the addition or loss of mass by reaction is eliminated. The differential equations have been solved together with the proposed equilibrium equations, and the material and charge balances between the different chemical species and elements. The model has been applied to predict and analyze the laboratory experimental data of C.A.J. Appelo and coworkers which had not been represented exactly using existing models. The model presented predicts and explains these experimental data perfectly.

Liquid–liquid–solid equilibria for ternary systems water + lithium chloride + pentanols

The authors wish to thank the Ministerio de Ciencia y Tecnologia (Spain) for the financial aid with of Project BQU2000-0212.

Physico-chemical characterization and leaching of tannery wastes

The toxicity of tannery wastes was examined and discussed using several analytical methods and tests: X-ray fluorescence (XRF), Scanning electron microscopy X-ray spectrometer dispersive energy microanalysis (SEM-EDX); gas chromatog raphy + mass spectrometry (GC-MS); acid nitric digestion; EP toxicity test; inductively coupled plasma atomic emission spectrometry (ICP-AES); biotoxicity tests with Photobacte rium phosphoreum, Daphnia magna and Sprague-Dawley (rats); and other conventional tests. A comparison between the ele ments detected by X-ray fluorescence, scanning electron microscopy + X-ray spectrometer dispersive energy microanalysis and inductively coupled plasma atomic emis sion spectrometry after nitric acid digestion was carried out. A valoration of toxicity, considering the elements and com pounds detected and the biotoxicity tests was done for each type of waste. Twenty-four samples of semi-processed leather trimmings and shavings, crust or finished chrome-tanned leather trim scraps and sludges from settling in the effluent streams were analyzed.

Liquid-liquid-solid equilibria for ternary systems of water + potassium chloride + pentanols

The authors wish to thank the DGICYT (Spain) for the financial aid for the Project PB96-0338. N. Barnes acknowledges a grant from “Agencia Espanola de Cooperacion Internacional”, Programa de Cooperacion Interuniversitaria/AL.E (1999).

The influence of temperature on the liquid-liquid-solid equilibrium of the ternary system water-potassium chloride-2-propanol

Abstract The lowest temperature at which waterKCl2-propanol mixtures cannot be split has been determined as 25.3°C. Seven diagrams of liquid-liquid-solid equilibria for the ternary system waterpotassium chloride-2-propanol around this temperature have been measured and the transition between their two different shapes has been studied.

Quaternary liquid—liquid equilibrium: water—ethanol—2-ethylhexanol—decalin at 25°C. Unusual shape of the solubility surface

Abstract Mutual solubility and tie line data at 25°C are presented for the quaternary system water—ethanol—2-ethylhexanol—decalin. The experimental results show unusual features such as a large hump in the solubility surface. This unusual behaviour can be associated with quaternary systems containing two pairs of partly-miscible compounds with very different solubilities.