Abstract
The crystallization of gypsum from supersaturated solutions in dependence on the molar [Ca2+] : [SO42−] ratio 0,26 : 0,15 and 0,35 : 0,15 in the presence of the sodium carboxymethylcellulose (CMC, with the degree of polym- erization of 1000 units) and NaCl was investigated at 25C. The efficiency of inhibition was estimated from measure- ments of change in Ca2+ concentration during the precipitation process. It was found that increasing the calcium ions content in solution compared to sulfate ions results in decrease in the induction period of crystallization. At a polymer concentration of 1,0 g/L and sodium chloride concentration of 0,7 mol/l the induction period of gypsum crystallisation in a supersaturation of the calcium sulfate solution with the molar rate of [Ca2+] : [SO42−] of 0,35 : 0,15 increases from several minutes to one hour. Further increasing the sodium chloride concentration up to 2,0mol/l did not result in change in the induction period of crystallization. This enables the preparation of supersaturated calcium chloride solu- tions using brines for the sealing of porous rocks, cracks, and joints of soil formations.The results of the phase analysis confirmed that salt precipitates in the form of gypsum.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Вестник Пермского университета. Серия «Химия» = Bulletin of Perm University. CHEMISTRY
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
