Engineering Industrial Catalysts: A Personal Journey

Jan­u­ary 2019
Dr. Car­mo Pereira
DuPont Clean Tech­nolo­gies

Abstract: Indus­tri­al reac­tors enable chem­i­cal trans­for­ma­tions that may upgrade the qual­i­ty of the feed, pro­duce chem­i­cals, and/or reduce process pol­lu­tants. The cat­a­lysts in these reac­tors are engi­neered to obtain the required (steady state) through­put of prod­uct over a cer­tain time. In addi­tion to through­put, there are addi­tion­al com­mer­cial­iza­tion con­straints that involve cost, uptime, emis­sions, and project tim­ing. The prop­er design of the cat­a­lyst and reac­tor often is key to the suc­cess­ful deploy­ment of the process.
In addi­tion to iden­ti­fy­ing the active site and the reac­tion mech­a­nism, addi­tion­al appli­ca­tion devel­op­ment work is required to com­mer­cial­ize a cat­a­lyst. The active site must func­tion with­in a range of oper­at­ing con­di­tions and in the pres­ence of impu­ri­ties that may impact activ­i­ty and selec­tiv­i­ty. Reac­tor pres­sure drop con­straints can dic­tate the size and struc­ture of the cat­a­lyst. The avail­abil­i­ty of active sites in a pel­let is max­i­mized by opti­miz­ing its size, shape and pore struc­ture to min­i­mize heat and mass trans­port lim­i­ta­tions. The num­ber of active sites in a cat­a­lyst may dra­mat­i­cal­ly decrease with time due to poi­son­ing, mask­ing, sin­ter­ing, or pore block­age. An under­stand­ing of the deac­ti­va­tion mech­a­nism under oper­at­ing con­di­tions pro­vides a basis for the reac­tor oper­at­ing strat­e­gy and for siz­ing reac­tors that have a war­rant­ed life. A process flow­sheet con­tain­ing a use­ful reac­tor mod­el may be sub­se­quent­ly val­ue-engi­neered to cost-effec­tive­ly meet the pro­cess­ing objec­tive.
This talk will present sev­er­al vignettes from the author’s expe­ri­ence where chem­i­cal reac­tion engi­neer­ing method­olo­gies were used to engi­neer indus­tri­al cat­a­lysts used in petro­chem­i­cal, chem­i­cal, and envi­ron­men­tal appli­ca­tions.