Alteration of lead silicate glasses due to leaching in heated acid solutions

Quantitative studies on the dissolution of Pb in an acid solution were conducted to understand the etching mechanism in PbO-SiO2-B2O3 glasses. In this study, the etching was done on bulk glasses of a PbO-SiO2-B2O3 system with a HNO3 solution at 40°C, and the surface structure of the glasses and ion dissolution behavior were analyzed using X-ray photoelectron spectroscopy (XPS), Raman spectrophotometer, and inductive coupled plasma spectrometry, respectively. The results showed that Pb (1.5-5.5 %) and B (0.8-3 %) ions are the major components etched. Small amounts of Si, Al, Ti, and Zr were detected in the etching solution. The analysis of O1s in the XPS peaks showed that the ratio of non-bridging oxygen (NBO) to bridging oxygen (BO) changed from 1:2.7 to 1:0.6 after leaching with the HNO3 solution. The Si-O-Pb and Si-O-Si bindings on the glass surface appeared to be a silicon-rich region where Si-O binding occurs after etching.

show abstract

“…2 and 3; this correlation was also observed in a previous work [10]. The reason can be attributed to the surface cracks obtained by etching.…”

Section: Resultssupporting

confidence: 86%

Etching behavior of Pb ion from PbO-B2O3-SiO2 glasses in HNO3 solution

Kim¹,

Hwang

Lee

et al. 2009

Met. Mater. Int.

View full text Add to dashboard Cite

show abstract

“…Figure 3 shows the changes in recovery rates of lead, aluminum, and Silica leached from the activated samples with variations of the rotational speed of the milling operation. Lead recovery was the key point in this research, and the chemical reaction (eq 1) of funnel glass in acid solution can be used to represent the lead dissolution (Bonnet et al, 2003). pathway, where the silica recovery rate remained low with all the samples, irrespective of the milling operation.…”

Section: Resultsmentioning

confidence: 99%

“…Silica forms the network structure of the glass and is very difficult to extract (Scholze, 1982;Bonnet et al, 2003). The recovery rate for silica was essentially 0% at 30…”

Section: Influence Of Leaching Temperaturementioning

confidence: 99%

Lead recovery from cathode ray tube funnel glass with mechanical activation

Yuan

Zhang

et al. 2012

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

In the disposal of electronic waste, cathode ray tube (CRT) funnel glass remains an urgent environmental problem because of its high lead content. This research developed mechanical activation as a pretreatment process, and it proved to be an effective method for extracting lead from CRT funnel glass. The effects of mechanical activation on the structural changes of CRT funnel glass were investigated using X-ray diffraction (XRD), particle size analysis, specific surface area (SSA), and a scanning electron microscope (SEM). Nitric acid leaching behaviors of the activated CRT funnel glass were studied by varying several parameters: leaching time, liquid-to-solid ratio, acid concentration, and heating temperature, as well as various conditions of activation. The lead recovery rate was observed to increase rapidly, particularly with increases in activation time and leaching temperature, but to vary relatively less under other experimental parameters. Under the optimal leaching conditions, the lead recovery rate for funnel glass activated for 2 hr at the rotational speed of 500 rpm (by ball mill) reached 92.5%, compared with 1.2% from the unactivated sample.Implications: CRT funnel glass containing lead has become a serious environmental problem facing the whole world. In order to dispose of CRT funnel glass, some technologies have been developed. However, these technologies are associated with higher operation and maintenance costs. In this study, mechanical activation was introduced to change the physicochemical properties of CRT funnel glass, which can transform the glass into an easily dissolved one. Under atmospheric pressure leaching conditions, good recovery rate for lead can be achieved and the residue has wide uses. The process can be applied to treat other leaded glass or leadcontaining wastes.

show abstract

“…All these products are expected to be of high quality and resistant to various types of corrosion without loss of utility properties. Therefore glazes must to some extent withstand the contact with water, acid or alkali media and other aggressive environments [8][9]. Chemical resistance of glassy coatings is a significant parameter of the utility of many ceramic products.…”

Section: Introductionmentioning

confidence: 99%

Characterization of the Interaction Between Glazes and Ceramic Bodies

Kavanová¹

2017

Ceramics - Silikaty

View full text Add to dashboard Cite

Alteration of lead silicate glasses due to leaching in heated acid solutions

Cited by 48 publications

References 8 publications

Etching behavior of Pb ion from PbO-B2O3-SiO2 glasses in HNO3 solution

Etching behavior of Pb ion from PbO-B2O3-SiO2 glasses in HNO3 solution

Lead recovery from cathode ray tube funnel glass with mechanical activation

Characterization of the Interaction Between Glazes and Ceramic Bodies

Contact Info

Product

Resources

About