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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">zldm</journal-id><journal-title-group><journal-title xml:lang="ru">Заводская лаборатория. Диагностика материалов</journal-title><trans-title-group xml:lang="en"><trans-title>Industrial laboratory. Diagnostics of materials</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1028-6861</issn><issn pub-type="epub">2588-0187</issn><publisher><publisher-name>ООО «Издательство «ТЕСТ-ЗЛ»</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.26896/1028-6861-2019-85-6-5-10</article-id><article-id custom-type="elpub" pub-id-type="custom">zldm-1001</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>АНАЛИЗ ВЕЩЕСТВА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>SUBSTANCES ANALYSIS</subject></subj-group></article-categories><title-group><article-title>METAL-ORGANIC COMPLEXES IN ENVIRONMENTAL SOLID SAMPLES: ON THE SELECTIVITY OF PYROPHOSPHATE EXTRACTION</article-title><trans-title-group xml:lang="en"><trans-title>METAL-ORGANIC COMPLEXES IN ENVIRONMENTAL SOLID SAMPLES: ON THE SELECTIVITY OF PYROPHOSPHATE EXTRACTION</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Fedotov</surname><given-names>P. S.</given-names></name><name name-style="western" xml:lang="en"><surname>Fedotov</surname><given-names>P. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>4 Leninsky prospect, 119049, Moscow</p></bio><bio xml:lang="en"><p>4 Leninsky prospect, 119049, Moscow</p></bio><email xlink:type="simple">fedotov_ps@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Dzhenloda</surname><given-names>R. Kh.</given-names></name><name name-style="western" xml:lang="en"><surname>Dzhenloda</surname><given-names>R. Kh.</given-names></name></name-alternatives><bio xml:lang="ru"><p>4 Leninsky prospect, 119049, Moscow; 19 Kosygin st., 119991, Moscow</p></bio><bio xml:lang="en"><p>4 Leninsky prospect, 119049, Moscow; 19 Kosygin st., 119991, Moscow</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Drozdov</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Drozdov</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Lomonosov Moscow State University, Faculty of Chemistry</p></bio><bio xml:lang="en"><p>1 bld. 3 Leninskye Gory, 119991, Moscow</p></bio><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Karandashev</surname><given-names>V. K.</given-names></name><name name-style="western" xml:lang="en"><surname>Karandashev</surname><given-names>V. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>4 Leninsky prospect, 119049, Moscow; 6 Akademika Ossipyana st., 142432, Chernogolovka, Moscow region</p></bio><bio xml:lang="en"><p>4 Leninsky prospect, 119049, Moscow;  6 Akademika Ossipyana st., 142432, Chernogolovka, Moscow region</p></bio><xref ref-type="aff" rid="aff-4"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>National University of Science and Technology “MISiS”</institution><country>Россия</country></aff><aff xml:lang="en"><institution>National University of Science and Technology “MISiS”</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>National University of Science and Technology “MISiS”; Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences</institution><country>Россия</country></aff><aff xml:lang="en"><institution>National University of Science and Technology “MISiS”;  Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Lomonosov Moscow State University, Faculty of Chemistry</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Lomonosov Moscow State University, Faculty of Chemistry</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru"><institution>National University of Science and Technology “MISiS”; The Institute of Microelectronics Technology and High Purity Materials, Russian Academy of Sciences</institution><country>Россия</country></aff><aff xml:lang="en"><institution>National University of Science and Technology “MISiS”; The Institute of Microelectronics Technology and High Purity Materials, Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2019</year></pub-date><pub-date pub-type="epub"><day>09</day><month>07</month><year>2019</year></pub-date><volume>85</volume><issue>6</issue><fpage>5</fpage><lpage>10</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Fedotov P.S., Dzhenloda R.K., Drozdov А.А., Karandashev V.K., 2019</copyright-statement><copyright-year>2019</copyright-year><copyright-holder xml:lang="ru">Fedotov P.S., Dzhenloda R.K., Drozdov А.А., Karandashev V.K.</copyright-holder><copyright-holder xml:lang="en">Fedotov P.S., Dzhenloda R.K., Drozdov A.A., Karandashev V.K.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.zldm.ru/jour/article/view/1001">https://www.zldm.ru/jour/article/view/1001</self-uri><abstract><p>Sequential extraction procedures (SEP) have been widely used for the fractionation of trace elements in soils according to their physicochemical mobility and bioaccessibility. Potassium/sodium pyrophosphate in alkaline medium may be considered as the most appropriate extracting reagent for the recovery of amorphous metal-organic complexes, which play a very important role in biological, physical, and chemical processes in soil. However, the selectivity of pyrophosphate has been poorly studied. In the present work the ability of pyrophosphate to attack mineral inorganic phases of environmental solids was assessed using dynamic extraction, which allows one to minimize artifacts and mimic natural conditions. Samples of gabbro and granite containing nearly no organic compounds were taken as example. The eluents applied addressed exchangeable, specifically sorbed, bound to Mn oxides, and bound to metal-organic complexes fractions extractable by 0.05 M Ca(NO3)2, 0.43 M CH3COOH, 0.1 M NH2OH · HCl, and 0.1 M K4P2O7 at pH 11, respectively. As expected, pyrophosphate extraction leads to a partial dissolution of elements bound to inorganic compounds. The recovery of aluminum, iron, manganese, and rare earth elements by pyrophosphate is up to 4% of their total concentrations in samples. The results were discussed on the basis of coordination chemistry of pyrophosphate complexes. In general, pyrophosphate extraction could be further regarded to be sufficiently selective for the dissolution of metal-organic complexes while using SEP in environmental analysis, soil science, and biogeochemistry. Nevertheless, in the interpretation of the fractionation results, a partial dissolution of mineral inorganic phases should be taken into consideration, especially for soils with low content of organic compounds.</p></abstract><trans-abstract xml:lang="en"><p>Sequential extraction procedures (SEP) have been widely used for the fractionation of trace elements in soils according to their physicochemical mobility and bioaccessibility. Potassium/sodium pyrophosphate in alkaline medium may be considered as the most appropriate extracting reagent for the recovery of amorphous metal-organic complexes, which play a very important role in biological, physical, and chemical processes in soil. However, the selectivity of pyrophosphate has been poorly studied. In the present work the ability of pyrophosphate to attack mineral inorganic phases of environmental solids was assessed using dynamic extraction, which allows one to minimize artifacts and mimic natural conditions. Samples of gabbro and granite containing nearly no organic compounds were taken as example. The eluents applied addressed exchangeable, specifically sorbed, bound to Mn oxides, and bound to metal-organic complexes fractions extractable by 0.05 M Ca(NO3)2, 0.43 M CH3COOH, 0.1 M NH2OH · HCl, and 0.1 M K4P2O7 at pH 11, respectively. As expected, pyrophosphate extraction leads to a partial dissolution of elements bound to inorganic compounds. The recovery of aluminum, iron, manganese, and rare earth elements by pyrophosphate is up to 4% of their total concentrations in samples. The results were discussed on the basis of coordination chemistry of pyrophosphate complexes. In general, pyrophosphate extraction could be further regarded to be sufficiently selective for the dissolution of metal-organic complexes while using SEP in environmental analysis, soil science, and biogeochemistry. Nevertheless, in the interpretation of the fractionation results, a partial dissolution of mineral inorganic phases should be taken into consideration, especially for soils with low content of organic compounds.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>fractionation analysis</kwd><kwd>soils</kwd><kwd>metals</kwd><kwd>dynamic extraction</kwd><kwd>metal-organic complexes</kwd><kwd>pyrophosphate</kwd></kwd-group><kwd-group xml:lang="en"><kwd>fractionation analysis</kwd><kwd>soils</kwd><kwd>metals</kwd><kwd>dynamic extraction</kwd><kwd>metal-organic complexes</kwd><kwd>pyrophosphate</kwd></kwd-group><funding-group><funding-statement xml:lang="en">The authors would like to acknowledge the financial support from the Russian Science Foundation (project No. 16-13-10417).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Ure A. M. and Davidson C. M. 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