Synthesis of Hydronium-Potassium Jarosites: The Effect of pH and Aging Time on Their Structural, Morphological, and Electrical Properties

Abstract

Structural and morphological properties of hydronium-potassium jarosite microstructures were investigated in this work, and their electrical properties were evaluated. All the microstructures were synthesized at a very low temperature of 70 °C with a reduced reaction time of 3 h. An increase in the pH from 0.8 to 2.1 decreased the particle sizes from 3 µm to 200 nm and an increase in the aging time from zero, three, and seven days resulted in semispherical, spherical, and euhedral jarosite structures, respectively. The Rietveld analysis also confirmed that the amount of hydronium substitution by potassium in the cationic site increased with an increase in pH. The percentages of hydronium jarosite (JH)/potassium jarosite (JK) for pH values of 0.8, 1.1, and 2.1 were 77.72/22.29%, 82.44/17.56%, and 89.98/10.02%, respectively. Microstructures obtained in this work were tested as alternative anode materials and the voltage measured using these electrodes made with hydronium-potassium jarosite microstructures and graphite ranged from 0.89 to 1.36 V. The results obtained in this work show that with reduced particle size and euhedral morphology obtained, modified jarosite microstructures can be used as anode materials for improving the lifetime of lithium-ion batteries.

Doped Potassium Jarosite: Synthesis, Characterization and Evaluation as Biomaterial for Its Application in Bone Tissue Engineering

“…The jarosite-type compounds, represented by MFe 3 (SO 4 ) 2 (OH) 6 where M can be Na, K, Rb, Ag or NH 4 , have had a wide application in metallurgical and mineralogical processes [1][2][3][4][5]. Figure 1 shows a natural jarosite crystal [6] contrasted with the crystals obtained using the synthesis conditions similar to those shown in this paper [7]. They are often associated with acid-mine drainage, weathering of sulfide ore deposits, hydrothermal alterations, oxidation of pyrite or weathering in acid soils [8].…”

“…Therefore, this work demonstrates improvements in the synthesis method of the doped potassium jarosite, such as a low operating temperature (70 °C), doping with calcium, short synthesis time (3 h) and changes in pH. Therefore, this modified method [7] makes the synthesis of these kind of compounds economical and environmentally friendly. In this manner, the addition of other elements into the jarosite structure and the A natural crystal of jarosite-type compound [6], and (B).…”

“…In this manner, the addition of other elements into the jarosite structure and the A natural crystal of jarosite-type compound [6], and (B). Crystals of potassium jarosite obtained with the synthetic method described in this work [7].…”

“…The potassium jarosite with formula KFe 3 (SO 4 ) 2 (OH) 6 and whose mineral name is simply jarosite [1,12], has been employed in the zinc industry process to precipitate nondesired iron and other elements to facilitate the filtering stage [7,13]. Additionally, the recovery of valuable metals from jarosite residues has been addressed [14][15][16].…”

Raw data of silver extraction from sodium-silver jarosite using three different lixiviants in alkaline medium

“…The sodium-silver jarosite sample was previously synthetized and fully characterized in a previous work [1] ; details for the synthesis can be found in references [ 2 , 3 ]. The solid sample was sieved using Tyler sieves in the range −325/+400 mesh for the leaching experiments.…”