THERMODYNAMIC AND TRANSPORT PROPERTIES OF H-S GASES INCLUDING SULPHUR DIHYDRIDE: H2S.

This paper is devoted to the investigation of the thermodynamic and transport properties of gaseous sulphur dihydride (H2S).
Among toxic wastes, resulting from oil to fuel conversion, sulphur dihydride represents large quantities and its conversion to hydrogen and sulphur can be performed by various techniques among which thermal plasmas look very promising. The final objective is to meet the legal requirements for their conversion and the approach of any reactor implies to study the different aspects of the problem: thermodynamic and kinetic calculations to understand the chemical reactions and find the best technology of the reactor allowing a sufficiently long residence time to achieve the most efficient conversion, transport properties to optimise the reactor losses.
The composition, thermodynamic and transport properties at atmospheric pressure up to 20000 K, were calculated using the data bank and computer code ADEP. For composition calculations the code is derived from the White and Dantzig method which allows particularly to study, with an excellent relative precision, the formation of minor species.
The transport properties of hydrogen/sulphur system were calculated according to the Chapman-Enskog theory with the following approximations: third for electrical conductivity and for electron translational thermal conductivity, second for heavy species translational thermal conductivity, internal thermal conductivity and viscosity, and first for reactional thermal conductivity.
Hydrogen/sulphur systems are characterized by very high specific enthalpy: 23.3 MJ/kg at 5000 K for H2S, and high viscosity roughly: 0.2^*10⁻³ kg/m/s at 5000 K for H2S, and a rather high mean thermal conductivity: 4 J/(m.s.K) et 10000 K.