caa a22 4500 388021101 CHVBK 20180307124924.0 cr unu---uuuuu 161130e199801 xx s 000 0 eng 10.1557/JMR.1998.0003 doi S0884291400042400 pii (NATIONALLICENCE)cambridge-10.1557/JMR.1998.0003 Characterization of a new Ca-Cd hydroxide hydrothermally synthesized and its implications for cement isolation of Cd [Elektronische Daten] Mixtures of CaO-CdO (1 : 1) were hydrothermally treated in a pressure reactor at 200 °C and 200 psi of pressure during a period of 16 h. The evolution of the reaction was followed by x-ray diffraction (XRD), infrared spectroscopy (IR), and thermogravimetric (TG and DTG) analysis. Also, the composition of the filtered solutions was analyzed to determine the mechanism of the reaction as well as the thermodynamic solubility constant of the new compound formed. The results show that CaO and CdO react, giving rise to a new CaCd(OH)4 hydroxide whose thermodynamic solubility constant, 1.5 ± 0.4 × 10−11 M2, is six orders of magnitude lower than those of both Ca(OH) 2 and β-Cd(OH) 2. This low solubility constant justifies the Cd2+ concentration measured in the pore solution of cement matrices used to immobilize cadmium containing wastes. The mechanism of the reaction proposed is via dissolution of both Ca(OH) 2 and β-Cd(OH)2, Ca2+ and being the predominant species in solution. Copyright © Materials Research Society 1998 Gñni S. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain Macías A. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain Madrid J. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain Díez J. M. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain Journal of Materials Research Cambridge University Press 13/1(1998-01), 16-21 0884-2914 13:1<16 1998 13 JMR https://doi.org/10.1557/JMR.1998.0003 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1557/JMR.1998.0003 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gñni S. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain NATIONALLICENCE 700 1- Macías A. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain NATIONALLICENCE 700 1- Madrid J. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain NATIONALLICENCE 700 1- Díez J. M. Institute of Construction Science Eduardo Torroja CSIC, c) Serrano Galvache s/n, 28033 Madrid, Spain NATIONALLICENCE 773 0- Journal of Materials Research Cambridge University Press 13/1(1998-01), 16-21 0884-2914 13:1<16 1998 13 JMR CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge