Potentiometric method for determination of hydraulic activity of quartzcontaining powders
Автор: Frolova M.A., Lesovik V.S., Morozova M.V., Orekhova T.N.
Журнал: Nanotechnologies in Construction: A Scientific Internet-Journal @nanobuild-en
Рубрика: Manufacturing technology for building materials and products
Статья в выпуске: 1 Vol.17, 2025 года.
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Introduction. An important aspect of concrete mixture preparation technology is the exploration of methods to effectively utilize the properties of aggregates (fillers) in hardening multi-component systems. The most common binder composition is a mixture of a binder system with crushed quartz-containing polymineral sand. It is known that micro silica is classified as an active mineral additive (filler), the properties of which are characterized by the amount of Ca2+ ions absorbed from a saturated lime solution. Literature sources describe two types of analytical methods for determining pozzolanic activity. The first type that trace the change in the content of Ca(OH)2 over time during the pozzolanic reaction. The second type that aim to determine the physical and mechanical characteristics of the material under study. These characteristics reflect its ability to bind free calcium oxide into stable hydrate compounds. Previously applicability of the potentiometric method of analysis using an ion-selective electrode with pCa-function was demonstrated for the assessment of pozzolanic activity of highly dispersed materials. It should be noted to note that this electrochemical method of analysis which is functionally related to the concentration of the determined component in the tested solution, is very efficient in terms of expressiveness and labour intensity. The objective of the research is to validate the method for micro silica systems obtained by mechanical grinding of raw materials of polymineral sands from different deposits. The experiments were conducted using sands from the Arkhangelsk region deposits. The quartz sand (QS) was chosen as a reference object to establish the nature of change in the functional relationship of the measured potential of the electrode system from the volume of added Ca(OH)2 solution. Methods and Materials. The polymineral sand of the Krasnoflotsky-West deposit is categorised as alluvialmarine modern Quaternary sediments (am IV). The sand of the Kholmogorskoye deposit is quartz-feldspathic sand, which belongs to alluvial modern Quaternary sediments (a IV). The mineralogical composition of polymineral sands was determined by means of the semi-quantitative method, utilising the binocular microscope MBS-1. Fine sand powders were obtained by dry mechanical grinding in a Retsch PM100 planetary. The specific surface area of the obtained fine powders was measured by the Kozeny-Karman gas permeability method on a PSKh-10a apparatus. The potentiometric analysis was conducted using an apparatus comprising an electrode pair, consisting of a measuring electrode with pCa-function and a reference electrode connected to an Expert-001-3.0.1 ionometer. The reaction system was stirred using a magnetic stirrer. In order to ascertain the sorption capacity of silica-containing raw materials, a lime solution with a concentration and a suspension of fine sand powders were prepared in advance. Concurrently, the EMF (potential) of the system was measured, with constant stirring. The concentration of calcium ions, Cact, was then calculated based on the previously established calibration dependence, using the potential values (mV) obtained. In order to determine the activity of fine mineral powders of silica, the dependence between the values of the given concentration of calcium ions in lime solution when adding a certain volume of lime to the suspension of the studied sands and the concentration values obtained by potentiometric measurements was plotted. Results and Discussion. The obtained powders of quartz-containing polymineral sands, which had been finely dispersed, had the following specific surface values: quartz sand – 1020±31 m2/kg, Krasnoflotsky West – 465±14 m2/kg and Kholmogorskoye – 450±14 m2/kg. The given data on the specific surface of powders of natural origin allow for a comparative analysis of experimental potentiometric measurements. Concurrently, the dependence of the measured potential on the concentration of calcium ions in the solution for quartz sand suspension can be utilised as a reference, given the significantly high specific surface of the powder, thereby resulting in a more pronounced dependence E = f(Vadd). Relationship obtained the dependence of the measured potential of the electrode system on the volume of added Ca(OH)2 solution in a suspension of quartz sand (as a reference sample) and distilled water (as an idle experiment) shows that the nature of the change in the functional relationship of the analysed two samples (QS and H2O) is different. Concurrently, it can be observed that the incorporation of a lime solution into water (in accordance with the anticipated outcome) results in a nearly constant augmentation in the measured potential values, the magnitude of which is proportional to –lgCCa. Change of potential of electrode pair in suspension of quartz sand powder has character different from that mentioned above for water.
Polymineral quartz sand, pozzolanic activity, calcium oxide, calcium hydroxide concentration, sorption capacity
Короткий адрес: https://sciup.org/142243355
IDR: 142243355 | DOI: 10.15828/2075-8545-2025-17-1-32-41
Список литературы Potentiometric method for determination of hydraulic activity of quartzcontaining powders
- Lesovik V.S. Construction materials. Present and future. Bulletin of MGSU. 2017;12(1): 9-16.
- Lesovik V.S., Shakhova L.D., Kucherov D.E. Classification of active mineral additives for composite binders, taking into account the genesis. Vestnik BSTU named after V.G. Shukhov. 2012;(3):10-15.
- Cepurītis R., Wigum B.J., Garboczi E.J., Mørtsell E., Jacobsen S. Filler from crushed aggregate for concrete: Pore structure, specific surface, particle shape and size distribution. Cement & Concrete Composites. 2014;54: 2-16. 2. https://doi.org/ 10.1016/j.cemconcomp.2014.03.010
- Donatello M., Tyrer C.R., Cheeseman. Comparison of test methods to assess pozzolanic activity. Cement and Concrete Composites. 2010; 32(2):121-127.
- Pontes J., Santos Silva A., Faria P. Evaluation of Pozzolanic Reactivity of Artificial Pozzolans. Tech Publications, Switzerland, Materials Science Forum. 2013;433-438.
- Potapova E.N., Manushina A.S., Zyryanov M.S., Urbanov A.V. Methods for determining pozzolanic activity of mineral additives. Construction materials, equipment, technologies of the XXI century. 2017; 7-8: 29–33.
- Strokova V.V., Nelyubova V.V., Khmara N.O., Bukovtsova A.I., Denisova Yu.V. Expanded pearlite sand as an effective additive to astringent. Building materials. 2022;6:61-66.
- Sokolova Yu.V., Ayzenshtadt A.M., Frolova M.A., Shinkaruk A.A., Makhova T.A. Potentiometric method for estimating pozzolanic activity of highly dispersed materials. Nanotechnology in construction. 2023;15(4):349–358.
- Natural raw materials for construction purposes in the North Arctic region. Mineral resource base of the Arkhangelsk region. Ed. A.M. Ayzenshtadt, A.L. Nevzorova, V.S. Lesovik. Arkhangelsk. C(A)FU. 2011;148.
- Atlas of the Arkhangelsk Region. Scientific and Editorial Mapping Part of the GUGK. Moscow. 1976;72.
- Shamanina A.V., Kononova V.M., Danilov V.E., Frolova M.A., Ayzenshtadt A.M. Aspects of determining the surface activity of dispersed systems based on mineral powders. Materials Science. 2021;7:30-36.
- Summary of physicochemical values. Edition tenth, rev. and add. Ed. A.A. Ravdel and A.M. Ponomareva. St. Petersburg: “Ivan Fedorov”. 2003; 240.
- Syutova E.A., Dzhigola L.A. Study of kinetic regularities of solid-phase concentration of calcium ions by natural sorbents. Sorption and chromatographic processes. 2020;20(1):64–78.