METHOD OF DETERMINING CONTENT OF SALTS IN MEDICINAL-TABLE MINERAL WATER Russian patent published in 2017 - IPC G01N5/04 

FIELD: chemistry.

SUBSTANCE: invention relates to analytical chemistry of medicinal-table mineral water and can be used for rapid determination of concentration of salts therein, determining falsification. Method of determining content of salts in medicinal-table mineral water is characterised by measuring mass of non-volatile compounds in water after solvent removal and volatile compounds is carried out on mass-sensitive resonator of volume-acoustic waves with base frequency 8–10 MHz and silver electrodes with diameter not less than 5 mm on a quartz plate, placed in a frequency meter so that electrodes are arranged horizontally. Method then includes measuring initial oscillation frequency of resonator F₀ (MHz), fixing in portable holder, on upper electrode applying with a micro-syringe 1 mcl of analysed water sample without suspensions and drying droplet of solution in a drying chamber at temperature 95 °C for 15 minutes. Further, resonator is cooled for 5 minutes in a drying oven, installing, while holding legs, in a frequency meter and measuring repeatedly oscillation frequency F_c (MHz). Then change in oscillation frequency of quartz plate before application of water and after drying is calculated: ΔF=F₀-F_c (MHz) and content of salts in water (g/l) by equation , where 39,800 is a coefficient (g⋅MHz/l). After each analysis mechanical cleaning is carried out, removal of salts using a cotton applicator, wetted in distilled water and heating of cleaned resonator, making a conclusion on compliance of analysed water on mineralisation, which for medicinal table water ranges from 1 to 10 g/l.

EFFECT: technical result is development of a method which enables to determine content of salts in medicinal-table mineral water, intensify process of analysis, reducing electrical costs, establish falsification or compliance with GOST.

1 cl, 2 dwg