1. Hydrocracking is the process of converting high molecular weight Hydrocarbons items (VGO, Vacuum/atmospheric residues, etc.) into more valuable lighter petroleum products like LPG, gasoline, Kerosene, and diesel. While hydrotreating is the process of removing impurities like Sulfur, Nitrogen, Oxygen, metals, chloride, etc. from the petroleum products like gasoline, kerosene, and diesel.
2. Hydrocracking is used for conversion of HC into products while hydrotreating is used for feeds or final product treatment.
3. Hydrocracking requires severe operating conditions while hydrotreating use mild conditions.
4. Hydrocracking uses both treating and cracking functions of petroleum feed while hydrotreating uses only the treating of hydrocarbon.
For more details view the blogs
1. Hydrotreating Process in Oil Refinery
2. Hydrocracking Process in Oil Refinery