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1

Zasoby uranu w Polsce – możliwości pozyskiwania uranu ze źródeł niekonwencjonalnych

100%

Kiegiel K. , Zakrzewska-Kołtuniewicz G.

Postępy Techniki Jądrowej

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2018

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tom z. 2

17--22

PL

W artykule omówiono niekonwencjonalne zasoby uranu w Polsce oraz przedyskutowano możliwość ich eksploatacji. Polska posiada jedynie złoża ubogich rud uranu. Najbardziej perspektywiczne zasoby to ordowickie łupki dictyonemowe o koncentracji uranu w zakresie 75-250 ppm oraz piaskowce syneklizy perybałtyckiej, gdzie koncentracja tego pierwiastka dochodzi miejscami nawet 1,5%. Uran może być również odzyskiwany z odpadów przemysłowych różnego pochodzenia, m. in. z przemysłu miedziowego i produkcji nawozów fosforowych.

EN

The article presents the unconventional resources of uranium in Poland and discusses the possibility of their exploitation. In Poland there are only low-grade uranium ores. The most perspective resources of uranium are the Ordovician dictyonema shale with uranium concentrations in the 75-250 ppm range and the sandstones of Peribaltic Syneclise, where the concentration of this element reaches locally up to 1.5%. Uranium can also be recovered from industrial waste of various origins, inter alia, waste from the copper industry and from the production of phosphate fertilizers.

2

Highly Diastereoselective Addition of Grignard Reagents to N-Glyoxyloyl-(2R0-bornane-10,2-sultam-Comparative Studies

80%

Raszplewicz K. , Sikorska L. , Kiegiel K. , Jurczak J.

Polish Journal of Chemistry

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2002

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tom Vol. 76 / nr 11

1595-1600

EN

N-Glyoxyloyl-(2R)-bornane-10,2-sultam (3), readily prepared from (2R)-bornane-10,2- sultam (1), was used in the Grignard reaction with methylmagnesium bromide (4a), phenylmagnesium chloride (4b), benzylmagnesium chloride (4c), allylmagnesium chloride (4d), and vinylmagnesium bromide (4e). Reactions of 3 with Grignard reagents 4a-d led to the desired adducts 5 with predominance of the (14S)-diastereoisomer. The reaction of 3 with vinylmagnesium bromide (4e) failed to give the adduct of type 5. Stereochemical models for the reactions studied are proposed.

3

Diastereoselective Addition of Grignard Reagents to Chiral alfa-Ketoimides Derived from Oppolzer's Sultam

70%

Raszplewicz K. , Sikorska L. , Kiegiel K. , Bałakier T. , Jurczak J.

Polish Journal of Chemistry

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2005

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tom Vol. 79 / nr 12

1901-1907

EN

Additions of various Grignard reagents to N-pyruvoyl- (3) and N-phenylglyoxyloyl- (2R)-bornane-10,2-sultam (4) under thermal and Lewis-acid catalytic conditions are studied. High diastereoselectivity was observed in these reactions, and in the case of vinylmagnesium bromide additions to -ketoimide 4 a change of direction of asymmetric induction was found.

4

Extraction of uranium from low - grade Polish ores : dictyonemic shales and sandstones

51%

Frąckiewicz K. , Kiegiel K. , Herdzik-Koniecko I. , Chajduk E. , Zakrzewska-Trznadel G. , Wołkowicz S. , Chwastowska J. , Bartosiewicz I.

Nukleonika

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2012

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tom Vol. 57, No. 4

451-459

EN

Leaching studies were performed to develop a suitable method for extraction of uranium from domestic uranium ores: dictyonemic shales and sandstones. The extracting procedure was composed of successive separation steps: crushing and grinding, acid or alkaline leaching, solid-liquid separation, and inductively coupled plasma mass spectrometry (ICP-MS) analyses of post-leaching solutions. The influence of such process parameters as temperature, pressure, particle size of solid material, kind of leaching solution and its concentration, on the recovery efficiency of uranium and accompanying metals were tested. The efficiency of uranium leaching with sulphuric acid solution achieved 81%. Satisfactory results were obtained for the alkaline leaching process. It was found that uranium can be selectively extracted by the alkaline leaching solution. Almost complete extraction of uranium from sandstones was achieved when a mixture of sodium carbonate and sodium hydroxide, with hydrogen peroxide as a leaching solution was used.

5

Dictyonema black shale and Triassic sandstones as potential sources of uranium

51%

Kiegiel K. , Zakrzewska-Kołtuniewicz G. , Gajda D. , Miśkiewicz A. , Abramowska A. , Biełuszka P. , Danko B. , Chajduk E. , Wołkowicz S.

Nukleonika

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2015

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tom Vol. 60, No. 3, part 2

515--522

EN

The main objective of the present study was an assessment of the possibility of uranium recovery from domestic resources in Poland. In the fi rst stage uranium was leached from the ground uranium ore by using acidic (sulfuric acid or hydrochloric acid) or alkaline (carbonate) solutions. The leaching efficiencies of uranium were dependent on the type of ore and it reached 81% for Dictyonemic shales and almost 100% for sandstones. The novel leaching routes, with the application of the helical membrane contactor equipped with rotating part were tested. The obtained postleaching solutions were concentrated and purifi ed using solvent extraction or ion exchange chromatography. New methods of solvent extraction, as well as hybrid processes for separation and purifi cation of the product, were studied. Extraction with the use of membrane capillary contactors that has many advantages above conventional methods was also proposed as an alternative purification method. The fi nal product U3O8 could be obtained by the precipitation of ‘yellow cake’, followed by calcination step. The results of precipitation of ammonium diuranate and uranium peroxide from diluted uranium solution were presented.