7 research outputs found
Studies on equilibrium of anthranilic acid in aqueous solutions and in two-phase systems: Aromatic solvent鈥搘ater
Utilization of Galvanic Sewage Sludge to Produce Alkali-Activated Materials
The development of civilization is causing an increase in the amount of industrial wastes, especially hazardous wastes. Among the methods of utilisation of this type of waste, the methods of stabilisation and solidification deserve attention, which enable the transformation of hazardous waste and the heavy metals it contains into an environmentally safe form, that is, immobilised. This paper proposes a method to stabilize and solidify galvanic sludge using geopolymerization reactions. The surface morphology was studied, and the chemical composition was analyzed using the SEM-EDS method. The presence of characteristic functional groups on the surface of the galvanic sludge and the geopolymer obtained on its basis was determined by FTIR spectroscopic analysis. Moreover, we evaluated of the recovery of selected heavy metals were performed on the basis of leaching tests. It was found that, as a consequence of geopolymerization of galvanic sludge, this hazardous waste is transformed in such a way that the heavy metals it contains, which occur in the form of soluble compounds are immobilised. In relation to the metals analyzed, reduction in solubility were obtained at a practical level of 100% for Zn and Mn, for the remaining metals, respectively, 94% for Cu and in the range of 40 to 90% for Pb. Analysis of the FTIR spectra showed that the ions of the metals studied were permanently immobilised in the aluminosilicate structure of the geopolymers obtained. This shows, that galvanic sewage sludge, as hazardous waste, is chemically transformed into inert waste that may be deposited in landfills
EFFICIENCY OF LEACHING TESTS IN THE CONTEXT OF THE INFLUENCE OF THE FLY ASH ON THE ENVIRONMENT
The leachability of heavy metals (Cu, Pb and Zn) from the coal fly ash samples was studied. The investigations executed using three leachability tests (USEPA, TCLP, ASTM). The effect of different parameters was determined (the diameter of ash grains, the kind of leaching solutions, pH of leaching solutions, the volume ratio of leaching solutions to the mass of ash samples, and the leaching time) on the leachability of the heavy metals from fly ash samples. Moreover, the influence of pH and changes in the redox potential of the leaching solutions as well as the presence of organic compounds that could potentially form complexes with metals and solubility changes of metals. The concentration of the metals studied (Cu, Pb and Zn) in all obtained solutions was determined by FAAS method. On the basis of the research investigations, optimal leachability conditions for Cu, Pb and Zn from fly ash in this study have been determined. We have also found that pH of the leaching solution, and the presence of organic compounds which have a potential capacity of complexion the metals are the important factors in determining the solubility of Cu, Pb and Zn
Por贸wnanie w艂a艣ciwo艣ci geopolimer贸w na bazie lotnego popio艂u ze spalania w臋gla i biomasy
Geopolymers are a new class of materials that can be synthesized using natural minerals, and waste
materials. Among these substrates, the use of fly ash is desirable as it involves the conversion of a copious waste material into a useful product. The aim of the research was geopolymers synthesis from coal fly ash and biomass
ash. Concentrated sodium hydroxide and sodium silicate solutions were used as activators in geopolymerisation
reaction. The results show that both coal fly ash and biomass ash can be utilized as source materials for the
production of geopolymers. The surface morphology and chemical composition analysis were examined for the
obtained geopolymers and ashes from coal and biomass combustion by SEM-EDS methods. It was found almost
total disappearance of spherical forms of grains and reduction the porosity of structure for geopolymer based on
fly ash from coal combustion. While the structure of the geopolymer based ash from biomass combustion is more
porous. The UV-VIS-NIR spectra were performed on the coal fly ash, biomass ash and geopolymers. They showed
that the obtained geopolymers possess optical and photocatalytic properties. The similarity of the geopolymer
network and the zeolite framework in relation to ion exchange and accommodation of metal ions open questions
on possibilities for the application of geopolymer materials as amorphous analogues of zeolite. The FT-IR spectra
analyses were used on the geopolymers before and after metals sorption. It was found that geopolymer based on
ash from biomass combustion has better sorption properties compared to geopolymer based on ash from coal
combustion.Geopolimery s膮 now膮 klas膮 materia艂贸w, kt贸re mog膮 by膰 syntetyzowane z u偶yciem naturalnych minera艂贸w i materia艂贸w odpadowych. W艣r贸d tych substrat贸w, u偶ycie popio艂u lotnego jest po偶膮dane poniewa偶 wi膮偶e si臋 z mo偶liwo艣ci膮 konwersji materia艂u odpadowego w u偶yteczny produkt. Celem bada艅 by艂a synteza geopolimer贸w z lotnego popio艂u w臋glowego oraz z popio艂u z biomasy. Jako aktywatory reakcji geopolimeryzacji by艂y stosowane st臋偶ony wodorotlenek sodu i roztw贸r krzemianu sodu. Rezultaty pokazuj膮, 偶e zar贸wno lotny popi贸艂 w臋glowy i popi贸艂 z biomasy mog膮 by膰 wykorzystane jako 藕r贸d艂o materia艂贸w do produkcji geopolimer贸w. Badania morfologii powierzchni i analiz臋 sk艂adu chemicznego dla otrzymanych geopolimer贸w i popio艂贸w ze spalania w臋gla i biomasy wykonano metod膮 SEM-EDS. Stwierdzono prawie ca艂kowity zanik form kulistych ziaren i zmniejszenie porowato艣ci struktury dla geopolimeru na bazie popio艂u lotnego ze spalania w臋gla. W przypadku geopolimeru na bazie popio艂u ze spalania biomasy wyst臋puje struktura bardziej porowata. Widma UV-VIS zosta艂y wykonane dla lotnego popio艂u w臋glowego, popio艂u z biomasy oraz geopolimer贸w. Pokazuj膮 one, 偶e otrzymane geopolimery wykazuj膮 w艂a艣ciwo艣ci optyczne i fotokatalityczne. Podobie艅stwo sieci geopolimeru i struktury zeolitu w zwi膮zku z wymian膮 jonow膮 i akomodacj膮 jon贸w metali otwiera pytania dotycz膮ce mo偶liwo艣ci zastosowania materia艂贸w geopolimerowych, jako bezpostaciowych analog贸w zeolitu. Widma FT-IR zosta艂y wykonane dla geopolimer贸w przed i po sorpcji metali. Stwierdzono, 偶e geopolimer na bazie popio艂u z biomasy ma lepsze w艂a艣ciwo艣ci sorpcyjne w por贸wnaniu do geopolimeru na bazie popio艂u lotnego ze spalania w臋gla
EVALUATION OF THE CONTENT OF SELECTED HEAVY METALS IN SAMPLES OF POLISH HONEYS
This paper presents the result of the determination of the total content of聽Cu, Pb and Zn聽by the method of atomic absorption spectrometry with atomization in an air-acetylene flame in Polish honeys samples. The research material was a honeydew, monofloral honey and buckwheat honey. For the mineralization of samples, the following solutions were applied:聽1) HNO3(conc), 2) HNO3(conc) and H2O2(conc)聽in the volume ratio equal to 4:1 and 3:1. On the basis of the results and recommended food standards the percentage of the recommended dietary allowances (RDA) in connection with the consumption of 100 g of product were estimated. To verify the results validation of analytical method used was carried out. It was included defining the following validation parameters values: the limit of detection and quantification; linearity and measurement range; repeatability and accuracy of the results. The contamination of the analyzed honeys by Pb is higher than the acceptable level of contamination of this element. The highest contents of Cu and Zn were characterized by monofloral honeys
Mobile fractions in dustfall and possible migration of metals to soil / Badania mobilnych frakcji metali w opadzie py艂owym i mo偶liwo艣膰 migracji metali do gleby
Poddano badaniom sta艂y opad atmosferyczny nad miastem Rzeszowem. Badano intensywno艣膰 opadu py艂owego (okresy kwartalne w latach 2011-2012) i jego w艂a艣ciwo艣ci fizykochemiczne (charakter kwasowo-zasad owy, rozpuszczalno艣膰 i roz- puszczalno艣膰 sekwencyjn膮, mobilno艣膰 frakcji). Intensywno艣膰 op^idu py艂owego by艂a zmienna: od 25 do 83 g nf2 na kwarta艂 i zale偶a艂a od pory roku. Stw ierdzono dominuj膮cy charakter kwasowy opadu z wyj膮tkiem okres贸w wiosenno-letnich oraz znacz膮cy udzia艂 frakcji rozpuszczalnej (18-31,5%) w opadzie (pH 7). Analizowano zawarto艣ci metali w opadzie i stwierdzono, 偶e wyst臋powa艂y w ilo艣ciach powy偶ej 1%: Fe, K, Ca, Na, w zakresie 0,1-1%: Mg, Zn, Na, Ca, Mn, Ni, Co, Cr oraz poni偶ej 0,1%: Cu, Bi, Cr, Mn, Ni. Stwierdzono, 偶e sta艂y opad mo偶e by膰 istotnym 藕r贸d艂em metali migruj膮cych w zr贸偶nicowanym stopniu (od 0,18% do 80% ich ca艂ko- witej zawarto艣ci w opadzie) do gleby