Patent ID: 9322793
Filing Date: 2016-04-26
CPC Classification: B01J,C07C,C10G,G01N

Claim Text:
1. A method for determining when to replace a guard bed material used to remove a catalyst poison from a feed based on a temperature change in an aromatic alkylation process, said method comprising the steps of: (a) providing a guard bed comprising a guard bed material, said guard bed having an inlet and a downstream outlet; (b) placing at least three guard bed temperature measuring devices proximate said guard bed, wherein a first guard bed temperature measuring device is located proximate said inlet to said guard bed, a third guard bed temperature measuring device is located downstream of said outlet of said guard bed, and one or more second guard bed temperature measuring devices are located downstream of said inlet of said guard bed and upstream of said outlet of said guard bed; (c) monitoring at least one temperature of said guard bed with each of said at least three guard bed temperature measuring devices; (d) supplying a benzene feed to said guard bed and at least intermittently supplying an alkylating agent feed to said guard bed from at least 1 hour up to 24 hours or more and then interrupted for periods of 10 to 15 days or more, wherein said feed comprises a catalyst poison; (e) contacting said feeds with said guard bed material under suitable guard bed treatment conditions to remove at least a portion of said catalyst poison from said feed and to form a treated feed, wherein said contacting produces an exothermic reaction and an increase in said guard bed temperature; (f) determining a first guard bed delta as the absolute value of the difference between said guard bed temperature at said first guard bed temperature measuring device and said guard bed temperature at said third guard bed temperature measuring device; (g) determining a second guard bed delta as the absolute value of the difference between said guard bed temperature at said first guard bed temperature measuring device and said guard bed temperature at said second guard bed temperature measuring device; and (h) replacing said guard bed material when the ratio of said second guard bed delta to said first guard bed delta is less than 1.