Simultaneous determination of iron and titanium in silicate rocks by using diantipyrinylmethane with dual-wavelength spectrophotometry

Simple and rapid spectrophotometric determination of trace titanium (IV) enriched by nanometer size zirconium dioxide in natural water

“…Table 3 presents the elution data (%) for Ti(IV) with different kinds and concentration of the eluent. As could be seen, 5 mL of 11.3 mol L −1 HF solution was an appropriate eluent for the determination of titanium by the spectrophotometry with 4 mL DAPM solution (as chromogenic agent) and 1 mL ascorbic acid solution (as masking agent), because (a) the condition constant K Ti-F of [TiF 6 ] 2− in 1.13 mol L −1 HF media (log K Ti-F = 11.57 ± 0.02) was high [29], so titanium could be eluted as [TiF 6 ] 2− by HF solution, and its elution data was 98.2%, (b) ZrO 2 could be dissolved by HF solution, becoming as [ZrF 6 ] 2− , (c) the condition constant of titanium and DAPM was higher than K Ti-F , fluoride ion as the ligand of titanium could be replaced by DAPM, and (d) the determination could not be interfered by the coexistence of high concentrations of zirconium [30] and fluoride [31].…”

Preparation of Water Hardness Colorimetric Card with Calcium Ion as Index

“…Therefore, accurately determining the concentration of calcium ions in water is of great significance for protecting human health and assessing the quality of drinking water [1] . The methods for analyzing calcium ion concentration include instrumental analysis methods and chemical analysis methods [2][3][4][5] , all of which require relatively professional operation requirements and large instrument equipment. For example, chemical analysis methods can accurately determine the content of calcium ions in water through titration analysis and gravimetric analysis but require strict and standardized experimental operations; instrumental analysis methods such as fluorescence spectroscopy and atomic absorption spectroscopy need expensive equipment, making it inconvenient to promote their use among the general public.…”