Germanium-containing dust as an intermediate by-product in the process of zinc hydrometallurgy , which often contains a large number of heavy metal substances. Due to the constraints of economic benefits and process technology, green and efficient treatment of germanium-containing dust is always a great challenge. In this work, XRD , ICP-OES, XPS , SEM and other characterization methods were used to analyze the existing state and quantity of main substances in germanium-containing dust. It was found that the occurrence state of germanium was closely related to sphalerite . At the same time, longer reaction time would lead to continuous hydrolysis of silicate, which would eventually affect the recovery of zinc, germanium and lead and the fixation of toxic substances. Therefore, the ultrasonic enhanced ammonium persulfate oxidation process was proposed to control the waste of resources and environmental pollution caused by the accumulation of germanium-containing dust. The final results showed that more than 95% of zinc and 89% of germanium were efficiently recovered, and heavy metals such as arsenic and cadmium were fixed in the liquid, and then concentrated in the purification and impurity removal stage. The residue after reaction is high-grade lead sulfate residue, which can be returned to the lead smelting system for recycling. In summary, the ultrasonic-enhanced ammonium persulfate process eventually makes all substances in germanium-containing dust harmless and resource treatment.
Si Shen,Lihui Gao,Shulei Li,Yanhong Liu,Hongyang Mao,Keyi Xu
Natural germanium (Ge)-containing minerals usually have low Ge concentrations, which poses many challenges for Ge enrichment and recovery. Therefore, it is imperative to explore efficient processes for Ge recovery from secondary resources. In this study, an alginate-based adsorbent (HCNTs-SA) with excellent adsorption performance for Ge was synthesized by optimal preparation conditions (2 % ( w / v ) sodium alginate (SA) concentration, a 1:15 mg HCNTs /mg SA hydroxylated carbon nanotubes (HCNTs) dosage, and 0.075 mol/L calcium chloride (CaCl 2 ) concentration). The adsorbent had a spherical shape with a layered void structure and improved swelling property (increased by 1200 %). The adsorption process of Ge by HCNTs-SA followed pseudo-second order kinetics and Langmuir adsorption isotherm, which indicated that the primary adsorption behavior was monolayer chemisorption with a maximum theoretical capacity of 151.44 mg/g at pH = 11 and 1.00 g/L adsorbent dosage, exceeding both pure alginate gels and previously reported materials. Meanwhile, HCNTs-SA exhibited high selectivity for Ge. In the Ge/Si binary system, the selectivity coefficients of Ge for HCNTs-SA were all greater than 1.00, indicating its exceptional affinity for GeO(OH) 3 − as compared to SiO 3 2− . According to FTIR, XPS analysis and DFT calculations, the primary adsorption mechanisms of Ge by HCNTs-SA were revealed as complexation and hydrogen bonding, with hydroxyl and carboxyl groups identified as key adsorption sites. This work demonstrates that HCNTs-SA is a promising adsorbent for selective Ge recovery from alkaline solutions.
The efficient recovery of germanium from complex secondary resources is a significant challenge in resource sustainability. In this study, a tartaric acid-functionalized nitrogen-doped hydrochar (NPB-TA) was synthesized for selective germanium (Ge) capture from aqueous solutions containing other metal ions. Adsorption experiments demonstrated that NPB-TA can be used in germanium solutions of varying pH and concentration, achieving a saturated adsorption capacity of 112.23 mg/g at pH = 3. The adsorption process was found to be in accordance with the Langmuir isotherm and pseudo-second-order kinetic models, indicating monolayer adsorption and chemisorption as the dominant mechanisms. Moreover, NPB-TA exhibited superior selectivity toward Ge (IV) even in binary systems with competing ions. Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Density functional theory calculations were applied to elucidate the adsorption mechanism. The mechanism involves synergistic coordination between Ge (IV) and surface-bound -OH/-COOH groups, with amino groups facilitating the formation of stable chelating rings containing C-O-Ge/C-N-Ge bonds. This study demonstrates that tartaric acid-modified N-doped biosorbent has potential for the selective recovery of germanium from aqueous solution.
危险品化学品经营许可证（带存储）