Recovery and Resource Utilization of Spent Hydrogenation Catalysts: A Review
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Summary
This summary is machine-generated.Recycling spent hydrogenation catalysts is crucial for environmental safety and the circular economy. This study reviews methods for efficient metal recovery and high-value utilization, offering strategies for industrialization.
Area Of Science
- Catalysis
- Environmental Science
- Materials Science
Background
- Escalating use of hydrogenation catalysts in petroleum refining generates hazardous spent catalysts.
- Spent catalysts pose environmental and health risks, necessitating efficient recovery and recycling.
- Circular economy principles emphasize the recovery of valuable metals from waste streams.
Purpose Of The Study
- To review and evaluate pretreatment, leaching, separation, purification, and utilization strategies for spent hydrogenation catalysts.
- To identify advantages and disadvantages of various recovery methods.
- To propose strategies for the industrialization of spent catalyst recycling.
Main Methods
- Review of solvent extraction for pretreatment and separation/purification.
- Evaluation of roasting-leaching for enhanced metal leaching.
- Analysis of regeneration and reuse processes for high-value utilization.
Main Results
- Solvent extraction is effective for oil removal in pretreatment and offers selective, mild separation.
- Roasting-leaching achieves higher metal leaching rates.
- Regeneration and reuse offer economic and environmental benefits over metallurgical methods, though technology requires further development.
Conclusions
- Efficient recycling of spent hydrogenation catalysts is vital for sustainable practices.
- Solvent extraction and roasting-leaching show promise for pretreatment and metal recovery.
- Further technological advancement is needed for mature industrialization of spent catalyst recycling.
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