A counter-current catalyst regenerator with at least two stages of counter-current contact along with a regenerator riser is proposed. Each stage may comprise a permeable barrier that allows upward passage of oxygen-containing gas and downward passage of coked catalyst into each stage, but inhibits upward movement of catalyst to mitigate back mixing and approximate true counter-current contact and efficient combustion of coke from catalyst. The regenerator riser may provide a passage to transport the catalyst and may serve as a secondary stage for coke combustion to provide the regenerated catalyst.

A counter-current catalyst regenerator with at least two stages of counter-current contact along with a regenerator riser is proposed. Each stage may comprise a permeable barrier that allows upward passage of oxygen-containing gas and downward passage of coked catalyst into each stage, but inhibits upward movement of catalyst to mitigate back mixing and approximate true counter-current contact and efficient combustion of coke from catalyst. The regenerator riser may provide a passage to transport the catalyst and may serve as a secondary stage for coke combustion to provide the regenerated catalyst.

The invention provides a process for the production of hydrogen, comprising catalytically decomposing a concentrated aqueous solution of potassium formate in a reaction vessel to form bicarbonate slurry and hydrogen, discharging the hydrogen from said reaction vessel, and treating a mixture comprising the bicarbonate slurry and the catalyst with an oxidizer, thereby regenerating the catalyst. Pd/C catalysts useful in the process are also described.

The invention provides a process for the production of hydrogen, comprising catalytically decomposing a concentrated aqueous solution of potassium formate in a reaction vessel to form bicarbonate slurry and hydrogen, discharging the hydrogen from said reaction vessel, and treating a mixture comprising the bicarbonate slurry and the catalyst with an oxidizer, thereby regenerating the catalyst. Pd/C catalysts useful in the process are also described.

The present disclosure provides systems and methods for regenerating a hydrogenation catalyst with reduced water consumption and/or shortened overall regeneration time. The method can include contacting a fouled hydrogenation catalyst with a first flushing medium comprising water and a gaseous phase comprising oxygen and optionally a second flushing medium comprising water and a gaseous phase comprising at least 90% nitrogen by volume. The method can further include treating the effluents of the flushing mediums by ion exchange resin to remove impurities in the effluents.

The present disclosure provides systems and methods for regenerating a hydrogenation catalyst with reduced water consumption and/or shortened overall regeneration time. The method can include contacting a fouled hydrogenation catalyst with a first flushing medium comprising water and a gaseous phase comprising oxygen and optionally a second flushing medium comprising water and a gaseous phase comprising at least 90% nitrogen by volume. The method can further include treating the effluents of the flushing mediums by ion exchange resin to remove impurities in the effluents.

A process for at least partially reactivating the catalytic activity of at least a partially deactivated catalyst following a reaction cycle, the catalyst having been used in a catalytic reaction process for hydrogenating an aromatic epoxide to produce a hydrogenated aliphatic epoxide; said process including contacting the at least partially deactivated catalyst with an oxygen-containing source at a temperature of less than about 100 C. and in the presence of a reactivation solvent for a pre-determined period of time sufficient to at least partially re-oxidize and reactivate the catalyst for further use; and a catalytic reaction process for hydrogenating an aromatic epoxide to produce a hydrogenated aliphatic epoxide including the above reactivating process step; and optionally including a step for washing the deactivated catalyst with a solvent prior to re-oxidizing the deactivated catalyst.

A process for at least partially reactivating the catalytic activity of at least a partially deactivated catalyst following a reaction cycle, the catalyst having been used in a catalytic reaction process for hydrogenating an aromatic epoxide to produce a hydrogenated aliphatic epoxide; said process including contacting the at least partially deactivated catalyst with an oxygen-containing source at a temperature of less than about 100 C. and in the presence of a reactivation solvent for a pre-determined period of time sufficient to at least partially re-oxidize and reactivate the catalyst for further use; and a catalytic reaction process for hydrogenating an aromatic epoxide to produce a hydrogenated aliphatic epoxide including the above reactivating process step; and optionally including a step for washing the deactivated catalyst with a solvent prior to re-oxidizing the deactivated catalyst.

A counter-current catalyst regenerator with at least two stages of counter-current contact along with a regenerator riser is proposed. Each stage may comprise a permeable barrier that allows upward passage of oxygen-containing gas and downward passage of coked catalyst into each stage, but inhibits upward movement of catalyst to mitigate back mixing and approximate true counter-current contact and efficient combustion of coke from catalyst. The regenerator riser may provide a passage to transport the catalyst and may serve as a secondary stage for coke combustion to provide the regenerated catalyst.

A counter-current catalyst regenerator with at least two stages of counter-current contact along with a regenerator riser is proposed. Each stage may comprise a permeable barrier that allows upward passage of oxygen-containing gas and downward passage of coked catalyst into each stage, but inhibits upward movement of catalyst to mitigate back mixing and approximate true counter-current contact and efficient combustion of coke from catalyst. The regenerator riser may provide a passage to transport the catalyst and may serve as a secondary stage for coke combustion to provide the regenerated catalyst.