A complex approach to the extraction of gallium from a carbon concentrate (CC), a waste product of the aluminum industry, was considered. Ashing of CC made it possible to remove the main component - carbon and obtain ash, which is an oxide mineral-like compound, from which gallium was leached with solutions of inorganic acids and their mixtures. The maximum degree of leaching (98%) of gallium was achieved with 6 M HCl for ash after ashing the CC at 600 degrees C. It was shown that Purolite anion exchangers with highly basic tertiary and quaternary ammonium base groups recovered gallium(III) from 2 to 10 M HCl, where the sorption equilibrium was attained after 60 min. The maximum extraction was observed from 6 M HCl. Under optimal conditions, the maximum sorption capacities for gallium(III) were achieved for Purolite A300 (2.7 mmol g(-1)) and Purolite A500 (2.2 mmol g(-1)) sorbents. Gallium(III) was quantitatively (99%) eluted from the sorbents with distilled water. Sorption of gallium(III) and its subsequent desorption with water made it possible to separate it from the predominant amounts of transition metal ions: Fe(III), Ni(II), Co(II), Zn(II), V(V) and other cations: Al3+, Ca2+, Mg2+, Na+ and K+. The addition of sodium hydroxide to the concentration of 200 g L-1 resulted in the cementation of gallium on aluminum gallama (liquid gallium-aluminum alloy).

Министерство науки и высшего образования Российской Федерации Российская академия наук Научный совет по неорганической химии РАН Научный совет по аналитической химии РАН Научный совет по химической технологии РАН Российское химическое общество имени Д.И

A simple and available method for on-line preparation of the adsorbent and solid phase extraction procedure for multi-element determination by inductively coupled plasma mass spectrometry (ICP-MS) has been proposed. The adsorbent (Al2O3-PB-AC) was synthesised by sequential impregnation of Al2O3 with Polybrene (PB) and Alizarin Complexone (AC). Cd(II), Cr(III), Ni(II), Pb(II) and Zn(II) were quantitatively recovered using Al2O3-PB-AC from aqueous solutions at pH 6.5 and at a flow rate of 1.0 mL min(-1). All the elements can easily be eluted by 3.0 mL 0.5 M HNO3. A mini-column packed with 0.100 g Al2O3-PB-AC retained all elements quantitatively from up to 50 mL multi-element solution with an enrichment factor of 16.7. The relative standard deviation for five replicate determinations was 3.5%, 7.3%, 6.2%, 7.4% and 4.7% for Cd(II), Cr(III), Ni(II), Pb(II) and Zn(II), respectively, for determination of 5 mu g L-1 level. The developed method was applied for SPE-ICP-MS determination of Cd, Cr, Ni, Pb, Zn in snow and river waters.

Functionalized adsorbents with poly-(4,9-dioxododecane-1,12-guanidine) (SiO2-PDDG) and mercaptophenyl groups (MPhS) were used for the separation of Se(VI) and Se(IV) for the first time. Fixation of PDDG was characterized by capillary electrophoresis and TGA/DSC. The quantitative extraction of Se(VI) proceeded due to anion exchange at pH 3-7. The adsorption capacity of SiO2-PDDG for Se(VI) was 28 μmol g-1. Silicas with mercaptophenyl groups were used for the extraction of Se(IV) from solutions in the range of 2 M HCl - pH 6.5. The adsorption capacity of MPhS was 35 μmol g-1. A system of columns containing synthesized adsorbents was proposed for the separation of Se(VI) and Se(IV) and their subsequent determination by ICP-MS. Optimal parameters of adsorption include a flow rate of 1 mL min-1, pH of 5, and sample volume of 200 mL. Se(IV) was desorbed with 5 mL of 0.25 M 2,3-dimercapto-1-propanesulphonic acid and Se(VI) with 5 mL of 1 M HNO3. The preconcentration factor was 40. The limits of detection (3s) were 0.75 and 1.25 ng L-1 for Se(VI) and Se(IV), respectively. The proposed method (SPE-ICPMS) was used to determine selenium species in natural water and certified reference materials. The separation was carried out directly at the sampling site.

The effect of heat treatment conditions (temperature and time of isothermal holding, temperature of the start of cooling and cooling conditions) of a melt containing 50 mol.% Bi2O3 and 50 mol.% SiO2 on the phase composition and macro- and microstructure of solidification products was studied. The temperatures and ranges of macroscopic phase separation of the melt were determined. Using physicochemical methods (powder X-ray diffraction, optical and scanning electron microscopy, and atomic absorption analysis), it was established that depending on the melt cooling conditions, solidification gives crystals of metastable bismuth silicate Bi2SiO5, or a mixture of crystalline phases and glass, or glass. The crucial influence of the holding temperature and time and the melt cooling rate on the crystallization of metastable Bi2SiO5 and formation of crystals of stable phases was demonstrated.

Amino-immobilized (poly(4,9-dioxadodecane-1,12-guanidine, polydiallyldimethylammonium, hexadimethrin bromide, polyhexamethylene guanidine) silicas were proposed for chromium speciation for the first time. Adsorbents surface was characterized by TGA-DSC, FT-IR, CHN, XRD and SEM analysis. Polyamines were strongly fixed on the silica surface and were not washed off with solutions of 3M HNO3 and 20 g L-1 NaCl. Amino-immobilized silica quantitatively removed (R >= 99%) Cr(VI) from solutions at pH 4-7. Cr(III) was not recovered in this pH range, which makes it possible to separate Cr(VI) from Cr(III). The separation factor (K-Cr(VI)/Cr(III)) was >= 1.10(4). Silica-based adsorbents layer-by-layer immobilized with polyamines and 2-(1,8-dihydroxy-3,6-disulfo2-naphthylazo)benzenearsonic acid were proposed for quantitative removal of Cr(III) from aqueous solutions with pH 4-6 at 90 degrees C. A system of sequentially connected columns filled with selective adsorbents was used to separate the chromium species in stream at pH=5 and a flow rate of 1 mL min(-1). Chromium was determined after its elution with 5 mL of 2 M HNO3 at a flow rate of 1 mL min(-1) using ICP-OES or ICP-MS. The pre concentration factors for Cr(VI) and Cr(III) was 60. A two-column system was used for chromium speciation in technological solutions. The efficiency of chromium speciation was confirmed by state standard procedure.

A simple and highly efficient method for the determination of highly toxic arsenic species using non-covalently aminated silica is proposed. The polyamines including poly(hexamethyleneguanidine), poly(4,9-dioxadodecane-1,12-guanidine), hexadimethrine, and poly(diallyldimethylammonium) were tested as silica modifiers. The prepared adsorbents allow effective preconcentration of anionic species of arsenic from aqueous solutions. It was found that As(V) can be quantitatively extracted from solutions at pH 4.5-7.0 by the anion exchange mechanism in less than 5 min, while neutral at this pH As(III) was not adsorbed at these conditions. A reaction with 2,3-dimercapto-1-propanesulphonic acid, which resulted in the formation of the negatively charged complex of As(III) with adsorbents was used for its quantitative extraction from solutions with a pH of 3.5-6.5. A system of two cartridges filled with poly(diallyldimethylammonium) modified silica and the on-line reaction of As(III) with 2,3-dimercapto-1-propanesulphonic acid proceeding between the cartridges was used for separate preconcentration and determination of As(V) and As(III) at pH 5. The proposed method was used for four-year monitoring of natural water pollution by arsenic in the area of residence of the indigenous peoples of Tyva Republic (Russia).

Novel silica-based adsorption materials layer-by-layer modified with polyhexamethylene guanidine and Arsenazo I or Arsenazo III have been proposed for solid-phase extraction of rare earth elements (REE). Silica, modified with Arsenazo I, quantitatively extracted REE at pH 5.5 - 7.0, and silica, modified with Arsenazo III, at pH 2.0-6.0 with distribution coefficients of 2.9 center dot 10(3)-4.6 center dot 10(4) cm(3) g(-1). The adsorption capacity for REE was 1.25-2.85 mg g(-1). Silica, layer-by-layer modified with polyhexamethylene guanidine and Arsenazo III, was used for removal of REE from solutions after digestion of lignites and ashes after their burning.

Silica gel chemically modified with dithiocarbamate groups (DTCS) was used for separation and preconcentration of precious metals and their subsequent determination in geological samples and their processing products by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry. DTCS was characterized by TGA/DSC, FT-IR, and CHNS-analysis. DTCS quantitatively extracted Au3+, Pd2+, Pt2+, Pt4+ at 20 degrees C from 0.5 to 4.0 M HCl media and Rh3+, Ir4+, Ru4+, and Os4+ at 95 degrees C in the presence of 0.025 M SnCl2. Two-column procedure was proposed to separate precious metals from matrix components and to separate kinetically inert precious metals from kinetically labile ones.

Biosilica-based adsorbents prepared from rice husk, sequentially modified with polymeric polyamines and carboxyarsenazo were proposed for the preconcentration of 13 lanthanides, La, Sc, and Y. It is shown that the proposed adsorbent quantitatively extracted rare earth elements (REEs) from solutions with pH 3.5-6.5. Carrying out adsorption at pH 3.5-4.5 allows the quantitative separation of rare earth elements from accompanying ions of non-ferrous, alkaline and alkaline-earth metals. A procedure for solid-phase extraction followed by mass spectrometric determination (SPE-ICP-MS) of REEs has been developed, which includes passing of 100 mL of the analyzed solution (pH 4) through a column with the adsorbent at a flow rate of 1 mL min-1, elution of REEs with 5 mL 1 M HNO3 (a preconcentration factor of 20) and subsequent determination of elements in the eluate by inductively coupled plasma mass spectrometry (ICP-MS). The accuracy of the results was confirmed by the recovery test of spiked samples and by analysis of a Certified Reference Material. The limit of detection was 0.04-10.9 ng L-1. The procedure was used for determination of REEs in lignites from Krasnoyarsk Krai (Russia) and fumarole sediment from Kudryavy volcano of the Greater Kuril Chain (Sakhalin Oblast, Russia).

2-Mercapto-5-benzimidazolesulfonic acid (MBI), also noncovalently bound to a silica surface, is proposed as a reagent for the low-temperature luminescence determination of Cu(I), Ag(I), Au(I), and Pt(II). Luminescence excitation and luminescence spectra of metal complexes with MBI in solutions and on the adsorbent surface represent broad unstructured bands in the regions 250–400 and 450–700 nm, respectively. The developed procedures for the luminescence and sorption–luminescence determination of Cu, Ag, Au, and Pt with limits of detection at a level of 0.001–0.01 μg on 0.1 g of adsorbent are tested in the determination of metals in natural and industrial samples.

For the extraction-fluorimetric determination of nanogram amounts of codeine in human urine the use of the fluorescence of the toluene extract of the codeine ionic associate with eosin was proposed. The formed ionic associate was characterized by the intensive fluorescence with a maximum of 550 nm. It was shown that the fluorescence intensity of the codeine ion associate with eosin in toluene was 10 times higher than the intensity of its luminescence in carbon tetrachloride, and 3 times higher than its intensity in chloroform. The optimal conditions for the formation of the fluorescent ion associate of the positively charged codeine ion with a negatively charged form of eosin were determined. The maximum fluorescence intensity of the ion associate was observed during the toluene extraction from the aqueous solutions with pH of 6 - 8 and the eosin concentration in the range of 1·10 -5 -1·10 -3 mol·L -1 . The fluorescence intensity of the extract was maintained at the initial level for 24 hours. The extraction-fluorometric procedure for determining the nanogram amounts of codeine in human urine was developed. The limit of detection of codeine, calculated by 3s-criterion, was equal to 6 ng·ml -1 . The calibration curve linearity was maintained in the range of 30 – 320 ng·ml -1 . The procedure for the determination of codeine in real expert samples of urine was tested. The relative standard deviation did not exceed 0.08. The obtained results for the extraction-fluorimetric determination of codeine in human urine allowed recommending the developed procedure for its use in the solutions of certain tasks in the practice of the institutions of the corresponding profile. Keywords: Сodeine, determination, human urine, extraction, fluorescence (Russian) DOI: http://dx.doi.org/10.15826/analitika.2017.21.4.006 S.I. Metelitsa 1 , E.V. Kireeva 1 , V.V. Nemikhin 2 , S.V. Kachin 1 , V.N. Losev 1 , S.A. Sagalakov 1 1 Siberian Federal University, Svobodnyi pr., 79, Krasnoyarsk, 660041, Russian Federation 2 Krasnoyarsk Regional Bureau of Forensic Medical Examination, Mira pr., 35, Krasnoyarsk, 660049, Russian Federation

For the extraction-fluorimetric determination of nanogram amounts of codeine in human urine the use of the fluorescence of the toluene extract of the codeine ionic associate with eosin was proposed. The formed ionic associate was characterized by the intensive fluorescence with a maximum of 550 nm. It was shown that the fluorescence intensity of the codeine ion associate with eosin in toluene was 10 times higher than the intensity of its luminescence in carbon tetrachloride, and 3 times higher than its intensity in chloroform. The optimal conditions for the formation of the fluorescent ion associate of the positively charged codeine ion with a negatively charged form of eosin were determined. The maximum fluorescence intensity of the ion associate was observed during the toluene extraction from the aqueous solutions with pH of 6 - 8 and the eosin concentration in the range of 1·10 -5 -1·10 -3 mol·L -1 . The fluorescence intensity of the extract was maintained at the initial level for 24 hours. The extraction-fluorometric procedure for determining the nanogram amounts of codeine in human urine was developed. The limit of detection of codeine, calculated by 3s-criterion, was equal to 6 ng·ml -1 . The calibration curve linearity was maintained in the range of 30 – 320 ng·ml -1 . The procedure for the determination of codeine in real expert samples of urine was tested. The relative standard deviation did not exceed 0.08. The obtained results for the extraction-fluorimetric determination of codeine in human urine allowed recommending the developed procedure for its use in the solutions of certain tasks in the practice of the institutions of the corresponding profile. Keywords: Сodeine, determination, human urine, extraction, fluorescence (Russian) DOI: http://dx.doi.org/10.15826/analitika.2017.21.4.006 S.I. Metelitsa 1 , E.V. Kireeva 1 , V.V. Nemikhin 2 , S.V. Kachin 1 , V.N. Losev 1 , S.A. Sagalakov 1 1 Siberian Federal University, Svobodnyi pr., 79, Krasnoyarsk, 660041, Russian Federation 2 Krasnoyarsk Regional Bureau of Forensic Medical Examination, Mira pr., 35, Krasnoyarsk, 660049, Russian Federation

Sodium 2,3-dimercapto-1-propanesulfonate (unithiol) which forms complexes with copper(I), silver(I) and gold(I) with intense luminescence at 77 K was used for low-temperature luminescent determination of copper, silver and gold. Sorbent obtained by consecutively modification of silica with polyhexamethylene guanidine and unithiol quantitatively extracts copper(II), silver(I) and gold(III) in the pH range of 1-8. The luminescence-excitation and luminescence-emission spectra of copper(I), silver(I) and gold (I) complexes with unithiol, including the last bounded to the silica surface, are located in the range 200-350 nm and 500-700 nm, respectively. The methods of luminescent determination in solutions and sorption-luminescent determination of copper, silver and gold were developed. Sorption preconcentration and subsequent luminescent determination of components in the solid sorbent phase allow to reduce their limits of detection tenfold. Luminescent determination in solutions and sorption-luminescent determination techniques were used to determine copper in natural and technogenic waters and gold in gold-containing flotation concentrate.

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Silica gel, sequentially modified with polyhexamethylene guanidine and 8-oxyquinoline-5-sulfonic acid, extracts more then 99% of aluminium(III) from aqueous solutions with pH 4-6. The equilibration time is 5 min. Surface complexes of aluminium(III) with 8-oxyquinoline-5-sulfonic acid have yellow-green luminescence (lambda(max)= 485 HM) under UV irradiation (lambda(max)= 354 HM). This effect was applied in developing of procedure of sorption-luminescent determination of aluminium. Limit of detection was 0.02 mu g of Al(III) on 0.1 g of the sorbent. The calibration function was linear to 2 mu g of Al(III) per 0.1 g of the sorbent. The determination of aluminium is not effected by 10(2)-10(3)-fold amounts of Ca(II), Mg(II), Sr(II), Cd(II), 10-fold amounts of Fe(III) (in the presence of 0.01% of ascorbic acid), equal amounts of Cu(II), Zn(II), Co(Il), and saline content up to 1 g l(-1) (NaCl or Na2SO4). The procedure was used to determine aluminium(III) concentration in drinking and mineral water.

Silica gel chemically modified with 1,3,4-thiadiazol-2-thiol groups recovered 99% of the copper(II) from solutions of pH 4–6; the adsorption equilibrium was attained in no more than 5 minutes. During irradiation with ultraviolet light, a yellow-orange luminescence (λmax = 575 nm) of surface copper complexes appeared in the phase of adsorbent cooled to 77 K; it was used as an analytical signal in the procedure for the low-temperature adsorption-luminescence determination of copper concentration. The detection limit was 0.3 μ g/0.1 g adsorbent. The calibration graph was linear up to 50 μg/0.1 g adsorbent. The determination of copper concentration is not affected by 10000-fold amounts of Zn(II), Cd(II), Mn(II), Co(II), Ca(II), Mg(II), and Al(III) and 300-fold amounts of Fe(III). The procedure was used to determine copper concentration in natural and technogenic waters.

Силикагель, химически модифицированный 1,3,4-тиадиазол-2-тиольными группами, извлекает 99% меди(II) из растворов с рН 4–6 с временем установления сорбционного равновесия, не превышающим 5 мин. При облучении ультрафиолетовым светом охлажденного до 77 К сорбента в его фазе возникает желто-оранжевая люминесценция ( max = 575 нм) поверхностных комплексов меди, использованная в качестве аналитического сигнала при разработке методики ее низкотемпературного сорбционно-люминесцентного определения. Предел обнаружения составляет 0.3 мкг/0.1 г сорбента. Линейность градуировочного графика сохраняется до 50 мкг/0,1г сорбента. Определению меди не мешают 104-кратные количества Zn(II), Cd(II), Mn(II), Co(II), Ca(II), Mg(II), Al(III), 300-кратные – Fe(III). Методика использована при определении меди в природных и техногенных водах.