ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Cryometric Analysis of the Phase Diagrams  of Pseudobinary Systems of the System CaO • Si0₂ (CS)-2CaO • Al₂0₃ • Si0₂ (C₂AS)-CaO - Al₂0₃ - 2Si0₂ (CAS₂) 2. Results of the Analysis.

M. Eliášová, O. Žigo, and I. Proks

Institute of Inorganic Chemistry, Slovak Academy of Sciences, CS-842 36 Bratislava

Abstract: Using the cryometric analysis described in [1], we determined a mean value of the sum of number of moles of products ∑_i¹v(P_i(M))_l that were formed when a unit substance amount of ''formula'' admixture M was dissolved in solvent N under the condition of infinitely dilute solutions L(M in N), formed out of components of the system CS-C₂AS-CAS₂. The value ∑_i¹v(P_i(M))_l  is independent of ions Ca²⁺ present in all investigated melts. For solutions L(CS in C₂AS or in CAS₂) the value of∑_i¹v(P_i(CS))_l is-an-element-of [0.02; 0.06). Hence admixture CS contains polymeric ions of probable mean composition (SiO₃)_n^2n- (n >> 2). For solutions L( C₂AS or CAS₂ in CS) ∑_i¹v(P_i(M))_l is-an-element-of [1.1; 1.5]. When C₂AS or CAS₂ is added to the melt CS, a formal dissociation of one ''formula'' particle occurs and ''foreign'' particles are formed (n > 1). Approximately we can assume that both types of particle may occur in the melts C₂AS and CAS₂: a) polymeric ions formed out of n (n is probably a small integer - 2, 3, 4) ''formula'' particles C₂AS or CAS₂; b) ions Al³⁺ that are released from the ''formula'' particles at the formal polymerization reaction. For the mutual solutions C₂AS and CAS₂ it is apparent from the values ∑_i¹v(P_i(C₂AS))_l is-an-element-of [0.3; 0.4] and ∑_i¹v(P_i(CAS₂))_l is-an-element-of [0.1; 0.3] that mutually different polymeric ions of effective molar mass M_eff almost-equal-to (2.5-10)M_form(M) (M_form(M) is the ''formula'' molar mass of M) occur in the melts C₂AS and CAS₂. Number of types of the polyanions in the melts C₂AS and CAS₂, respectively, can be > 1. Ions Al³⁺ occur in the melts C₂AS and CAS₂ as well.

Full paper in Portable Document Format: 473a169.pdf

Chemical Papers 47 (3) 169–174 (1993)