Influence of iron ion additions on the thermal decomposition of basic zinc carbonate

Abstract

Thermal decomposition of pure basic zinc carbonate (BZC) and doped or mixed with iron ions were studied using TG, DTA and kinetics of isothermal decomposition. The TG and DTA investigations revealed that, the presence of iron ions retards the decomposition processes of (BZC). Also, the retardation effect increases on increasing of iron concentration up to 50 at.%. The curves of isothermal decomposition show the usual sigmoidal character. The decomposition velocity eontsant (K) values are plotted vs. liT according to Arrhenius equation gave a plot of good straight lines with activation energies of 43.7, 48.2, 53.2 and 57.1 kJ mo1-1 for pure (BZC) and incorporated with 1, 10, 30 and 50 at.% Fe 2+ respectively. The products of the thermal decomposition of pure BZC and mixed with iron ions are characterized using X-ray diffraction, IR spectroscopy, surface area determination and the surface porosity. These investigations showed that iron ions are effectively incorporated into zinc oxide lattice in the range of 30-50 at.%, which gave a ZnFe204 spinel.Mixed oxides, especially binary system, have been employed sucessfuUy in many industrial catalytic processes [1,2]. The combination of two transition metal oxides may affect their stoiehiometry and their surface, electrical, catalytic and thermal properties [3][4][5]. It was observed that the presence of foreign ion in the host lattice of solids markedly influences the reaction rate of solid-phase reaction [6]. This fact has been attributed to the change in the defect structure of reacting substances [7,8]. On addition it was found that [9,10], the active sites as well as the electronic structure of the semiconductor surface are changed in the presence of foreign cations.

Characterization of Zinc Carbonate Basic as a Source of Zinc in a Rodent Study Investigating the Effects of Dietary Deficiency or Excess

“…However, the observed weight loss was 23.3% (0.43% relative standard deviation), suggesting that nonvolatile impurities may be present in the test lot. In addition, the temperature of maximum weight loss (approximately 270 °C) in our investigation was slightly greater than that observed in similar studies (Said et al 1990), thus supporting the presence of non-volatile impurities. When these data are taken collectively with XRD observations, ZnO is a plausible minor component of the test lot of zinc carbonate basic.…”

“…These compounds have a variety of industrial applications and have been used as drilling fluid additives (Cameron 2005), used in respirators (Okutani et al. 1993, Zhang, Fortier, and Dahn 2004), and as synthetic precursors for reactive metal oxide fine particles (Said et al 1990, Koga and Tanaka 2005) for use in solar cells, cosmetic products, gas sensors, paints, pigments, and a variety of other products (Kanari et al 2004, Feng et al 2005, Cao et al 2009, Du, Liu, and Chen 2009, Zhang et al 2009, Anžlovar et al 2015).…”

Effect of Additives on Decomposition of Sodium Carbonate: Precombustion CO2 Capture Sorbent Regeneration

“…The initial decomposition product was identified as Na 2 SiO 3 , irrespective of the mixing ratio of Na 2 CO 3 /SiO 2 . Said et al studied the influence of iron additions on the thermal decomposition of zinc carbonate . They observed that the presence of iron retarded the decomposition.…”

Thermal analysis

“…Nitrates receive a lot a attention (99,100). Typical of the work on carbonates is the study showing the dependence of decomposition upon the pressure of C02 for Ag2C03 (101) and the influence of ionic additions to the decomposition of ZnC03 (102). In molten potassium pyrosulfate, the reactions of six metal nitrates were investigated by thermal analysis (103).…”