Purification and conversion processes for asphaltene-containing feedstocks

A process comprising:

• contacting a hydrocarbon feedstock with an effective amount of sodium metal and an effective amount of exogenous capping agent at a temperature of 250-500° C., to produce a mixture of sodium salts and a converted feedstock, wherein
• the hydrocarbon feedstock comprises hydrocarbons with a sulfur content of at least 0.5 wt % and an asphaltene content of from 2 wt % to 40 wt %;
• the sulfur content comprises asphaltenic sulfur and non-asphaltenic sulfur;
• the converted feedstock comprises hydrocarbon oil with a sulfur content less than that in the hydrocarbon feedstock and an asphaltene content less than that in the hydrocarbon feedstock;
• and
• the proportion of asphaltenic sulfur to non-asphaltenic sulfur in the converted feedstock is lower than in the hydrocarbon feedstock.

A process comprising:

• contacting a residual feedstock, the residual feedstock comprising hydrocarbons with a sulfur content of at least 0.5 wt % and an asphaltene content of from 2 wt % to 40 wt %;
• with
• a less than stoichiometric amount of sodium metal to the sulfur content of the residual feedstock, and
• an effective amount of exogenous capping agent at a temperature of 250-500° C., to produce a mixture of sodium salts and a converted feedstock, wherein
• the stoichiometric amount of sodium metal to sulfur content is the theoretical amount of sodium metal required to convert all sulfur content in the residual feedstock to sodium sulfide;
• the converted feedstock comprises a hydrocarbon oil with a sulfur content less than that in the residual feedstock and an asphaltene content less than that in the residual feedstock.

A process comprising:

• pretreating a hydrocarbon feedstock comprising impurities to provide a purified feedstock and a residual feedstock, wherein
• the purified feedstock comprises a lower concentration of impurities than the hydrocarbon feedstock before pretreatment, and
• the residual feedstock comprises a higher concentration of impurities than in the purified feedstock;
• contacting the residual feedstock with an effective amount of sodium metal and an effective amount of exogenous capping agent at a temperature of 250-500° C., to produce a mixture of sodium salts and a converted feedstock, wherein
• the residual feedstock comprises hydrocarbons with a sulfur content of at least 0.5 wt % and an asphaltene content of from 2 wt % to 40 wt %;
• the converted feedstock comprises a converted hydrocarbon oil with a sulfur content less than that in the residual feedstock and an asphaltene content less than that in the residual feedstock;
• and
• at least a portion of the converted hydrocarbon oil derives from asphaltenes in the residual feedstock.