Mullite–cordierite ceramic saggar is a necessary consumable material used in the synthesis process of LiCoO₂ that is easily eroded during application. In our study, we systematically investigated the characteristics and surface corrosion behavior of waste saggar samples. We divided the cross sections of waste saggar into the attached layer, hardened layer, permeability layer, and matrix layer. Then, we examined the high-temperature solid-state reactions between saggar powder and lithium carbonate or cobalt oxide to identify erosion reactants correlating with an increase in the number of recycled saggars. The results of time-of-flight secondary ion mass spectrometric analysis (TOF-SIMS) prove that the maximum erosion penetration of lithium can reach 2 mm. However, our morphology and elemental distribution analysis results show that the erosion penetration of cobalt was only 200 μm. When enough lithium carbonate reacted, lithium aluminate and lithium silicate were the main phases. Our X-ray computed tomography (X-ray CT) analysis results show that the change in phase volume before and after the reaction, including the generation of oxygen and carbon dioxide gas, led to the internal crack expansion of the material–saggar interface. Our results can contribute to improving saggar and upgrading waste saggar utilization technology.

ZSM-5 zeolite is a kind of high-value-added porous aluminosilicate zeolite. The use of the coal gasification slag utilization process by-product desilication liquid as a silicon raw material to replace the current raw materials such as water glass will help reduce production costs and achieve high-value utilization of solid waste. ZSM-5 zeolites for volatile organic compounds (VOCs) adsorption were prepared by a one-step hydrothermal method using the desilication solution prepared from coal gasification slag as the main silicon source and sodium source. The effects of crystallization reaction time, the crystallization temperature, the Na₂O/SiO₂ molar ratio, and the SiO₂/Al₂O₃ molar ratio on the relative crystallinity and the specific surface area of the ZSM-5 zeolite were investigated and optimized. The optical reaction conditions were as follows: a crystallization time of 12 h, a crystallization temperature of 170 °C, a Na₂O/SiO₂ molar ratio of 0.2, and a SiO₂/Al₂O₃ molar ratio of 200. The optimal ZSM-5 zeolite synthesized is hexagonal, with regular grains, a relative crystallinity of 101.48%, a specific surface area of 337.48 m²·g⁻¹, and a pore volume of 0.190 cm³·g⁻¹. And the optimal ZSM-5 zeolite was composed of SiO₂ content of 97.52 wt%, Al₂O₃ content of 1.58 wt%, Na₂O content of 0.33 wt%, and SiO₂/Al₂O₃ molar ratio of 104.93. Na₂O/SiO₂ molar ratio is 0.0033. The results of static adsorption experiments show that the static adsorption capacities of ZSM-5 zeolite for p-xylene, benzene, toluene, and butyl acetate were 118.85, 69.98, 68.74, and 95.85 mg·g⁻¹, respectively, which can effectively adsorb VOCs. The synthetic process of the ZSM-5 zeolite is a simple preparation process and short in synthesis time. The results of this study not only help to realize the high-value utilization of silicon components in solid waste, but also provide an economical and effective way to synthesize VOCs adsorption materials.

Scrapped saggars, used for the calcination of the cathode materials of lithium-ion batteries, contain large amounts of nickel, cobalt and manganese compounds, which have high economic value and significance to the ecological environment if recycled. This paper uses the life cycle assessment method to evaluate the environmental impact of the recycling process, compares its impact intensity with that of the direct disposal of Ni-Co-containing saggars and the production of corresponding products with alternative processes, and then compares the impact of each process. Sensitivity analysis of each material input and output item is carried out to find whether the input or output item that has a greater impact on the environment. The results show the following: (1) the environmental impact of the recovery of Ni-Co-containing saggars is much lower than that of equivalent products produced by alternative production methods, and the weighted person equivalent is only 14.5% of the alternative process; (2) from the perspective of processes, the crystallization and leaching processes demonstrate the greatest impact; and (3) among all input and output items, the sulfuric acid input in the reduction and leaching process, the potassium carbonate and steam input in the crystallization process, the potassium carbonate and potassium hydroxide input in the cascade separation process, and the ammonia input in the purification process are the items with the greatest environmental impact, accounting for 86.05% of the overall environmental impact sensitivity and becoming the focus of future process improvement.

High-alumina fly ash may potentially be a valuable source of Ga with a concentration of Ga at 80 mg/kg. Direct adsorption and enrichment of Ga from sulfuric acid leach liquor of high-alumina fly ash is developed in this study. The H-type chelating resin with two carboxy groups exhibited the best adsorption capacity for Ga. The maximum adsorption capacity for Ga was 55 mg/g resin with an adsorption time of 24 h, an initial Ga concentration of 500 mg/L, an adsorption temperature of 55 °C, and an initial acid concentration of 0.1 mol/L. The adsorption process of Ga was in good fit with the Langmuir isotherm and pseudo-second-order reaction kinetics model. The chemical adsorption rate was controlled by an internal diffusion mechanism. The resin had a high selectivity for Ga³⁺ with a K_d over 3600 compared with Fe²⁺, Al³⁺, K⁺, Ca²⁺, and Mg²⁺. The adsorption mechanism was found to be the ion exchange reaction between Ga and H of carboxy and hydroxyl groups. The concentration of Ga in sulfuric acid leach liquor from high-alumina fly ash achieved enrichment from 200 mg/L to 2 g/L. It is an attractive medium for large-scale Ga extraction from high-alumina fly ash.