Synthesis of ultramarine pigments from Na-A zeolite derived from kaolin waste from the Amazon

Ultramarine pigments were synthesized successfully from Na-A zeolite derived from kaolin waste. Na-A zeolite encapsulates the sulfur species formed and which act as chromophores, which circumvents their oxidation and the subsequent liberation of high levels of toxic gases during the reaction. Different Na-A zeolite matrices with various grain sizes (fine to coarse) were mixed with sulfur and sodium carbonate in various proportions to study the influence of these variables on the pigments’ colours and hues. After calcination at 500°C for 5 h, the products were characterized by X-ray diffraction, X-ray fluorescence and Raman spectroscopy and were classified by the Munsell system (colour and hue). Products with colour ranging from blue to green with various hues were obtained. Both colour and hue were affected by the amount of additives and by the particle size.

Colouristic criteria of S-matrix of the precarpathians brownish-podzolic gleyed soils

The scientific literature dedicated to the analysis of peculiarities of the soils colouring and interconnection the genetic horizons colour as well as separate morphological elements with their properties have been analyzed. The identification of colour of genetic horizons in 20 profiles of brownish-podzolic gleyed soils of Ukrainian and Polish Precarpathians has been conducted. The colour of investigated genetic horizons and separate morphological elements was determined according to both national and international systems. The analysis of the appropriateness of national approaches rejecting and usage of the Munsell scale as a primary method for determining the soil samples colour has been carried out. The results of the survey of the respondents with different professional training ascertained that visual determination of colour range within morphological description of the soil is completely subjective. The correctness of procedure depends on the experience of soil scientists and colour homogeneity of the soil sample. Using of the Munsell scale reduces the errors in the determination by 70–80 %, which allows recommending the very approach as the principal one for the field descriptions. Change of the investigated soils colour depending on the level of humidity has been established. The peculiarity of soil mass colour range depending on the aggregation and fractions size has been found out. Based on the colouristic analysis it has been confirmed that chemical and mineralogical composition is the main factor of heterogeneity of the investigated soils horizons colour. It has been found out that heterogeneity of the colour range, and the appearing of bleached zones (as the result of iron removing) and fine dust on the surface of the aggregations is associated with gleying processes, impulse redox regime and metamorfization of soil mass. It has been established that interdependence between the complex of statistical and fractal parameters, which indicates the relative optical heterogeneity of architectonics of the investigated soils ultra thin cuts which are characterized by optical heterogeneity on the macro-level. The processes of morphogenesis of self-similar elements of their architectonics cause the asymmetry and fluctuations of relative data and increasing of the half-width of the autocorrelation functions of orientation tomograms. Red and green shades are shown to be the basic components of the sample colour. Red ones are determined by red colour pigments, and the combination of red and green shades provides the formation of yellow tones. The possibility of data conversion from the Munsell system into the CIE-L*a*b* system with minor deviations has been shown. 2,5Y5 / 4 in Munsell system corresponds to the following data in the CIE-L*a*b* system: L* = 41,23; a* = 5,59; b* = 20,06 (manual calculation) and L* = 41,22, a* = 4,97, b* = 19,44 (automatic transfer using the computer program Munsell Conversion 4.01).