Volume 37 (2006): Issue 2 (December 2006)

Clinoptilolite from Dylągówka (Poland) with an external cation exchange capacity (ECEC) of 16 meq/100 g determined by adsorption of alkylammonium ions was treated with hexadecyltrimethylammonium (C16) and dioctadecyldimethylammonium (2C18) bromides in amounts equivalent to 1.0 and 1.5 ECEC. The products were characterized using IR spectroscopy and C and N determinations. The sorption of chromate on the modified mineral was measured spectrophotometrically as a function of pH, concentration of Cr(VI) or the proportion of the sorbent to solution. The amount of chromate removed from the solution continuously decreased with increasing pH in the range 1.3-10. At pH 2.6-3.1, the maximum adsorption of Cr(VI) by the organo-zeolites (103 and 124 mmol/kg) was observed for the samples modified using a 1.5 ECEC surfactant concentration. Considerably lower adsorption values (37 and 46 mmol/kg) were obtained with sorbents prepared using a 1.0 ECEC concentration of the alkylammonium ions.

An extensive hydrothermal polymetallic mineralization with a well developed oxidation zone rich in secondary minerals occurs in dolostones several hundred meters from the Karkonosze granite at Rędziny. Using XRD and FTIR methods, mineral phases representing transitional members of the olivenite-adamite solid solution have been identified. Electron microprobe analyses reveal the most common varieties to be zincian olivenite and cuprous adamite with compositions ranging from (Cu_1.17Zn_0.83)(AsO₄)(OH) to (Zn_1.38Cu_0.62)(AsO₄)(OH). The two minerals are subordinate in the weathering zone which can be characterized as having been a zone of low Cu²⁺ and Zn²⁺ activity and with mineralizing solutions of increased pH. A high Ca²⁺ concentration due to the ubiquitous presence of carbonate rocks resulted in the expansion of the stability field of another arsenate, conichalcite (or Zn-bearing conichalcite), which is a common mineral there.

The molecular character of organic matter in Triassic clays on the NW border of the Holy Cross Mts was determined in apolar, aromatic and polar fractions of extractable organic matter (OM) using GC-MS analysis. The contribution of terrestrial higher plants to the kerogene is revealed by the dominant presence of odd long-chain n-alkanes and by the occurrence of retene. Benzophenone, fluorenone, cyclopenta(def)phenanthrenone, antracenone and benzanthrone were among the compounds identified in polar fractions of the soluble organic matter. These commonly originate during strong oxidation of sedimentary organic matter. The aromatic fraction is characterised by the presence of phenyl derivatives (PhPAC) such as phenylnaphthalenes, terphenyls, phenyldibenzofurans and phenylphenanthrenes that are also products of the abiotic oxidation of organic matter. The oxidation processes that occurred during sedimentation and during early diagenesis resulted in a very significant decrease in the organic matter content in the clays. This decrease considerably influences their technological properties.

The presence of clausthalite in the area of old mining works near Dziećmorowice in the Sowie Mts (SW Poland) is reported here for the first time. The identification of the clausthalite is based on macro- and microscopic observations, reflectance measurements, chemical analyses and X-ray diffraction data. The clausthalite, together with uraninite, forms veinlets in a breccia comprising <50% calc-silicate rock fragments. Different polishing hardnesses suggest some variation in the mineral structure of individual clausthalite grains. Chemical spot analyses do not reveal elements other than Pb and Se though calculated unit-cell parameters may suggest minor substitution of S for Se.

Celestite containing very low amounts of barium occurs in weathering reaction zones developed on the Pińczów limestone exposed to the polluted atmosphere of Cracow. The mineral occurs both in limestone pore spaces filled with gypsum and in black gypsum crust. The Pińczów limestone contains ca 500 ppm strontium which was released during the reaction with atmospheric pollutants. The nucleation and growth of celestite, requiring significant concentration of components in evaporating solutions, is associated with gypsum crystallization.