Siliceous Zeolite-supported Palladium Catalysts for Methane Oxidation

Meeting Program — January 2018

Jing Lu
Jing Lu
Staff Sci­en­tist at Clean Air Divi­sion
John­son Matthey Inc.

 

Abstract — Cat­alyt­ic oxi­da­tion of methane in the pres­ence of excess of oxy­gen is of great inter­est as a prac­ti­cal tech­nol­o­gy to reduce methane emis­sions from com­pressed nat­ur­al gas vehi­cles, engines, and tur­bines. Typ­i­cal com­mer­cial methane oxi­da­tion cat­a­lysts are alu­mi­na-sup­port­ed pal­la­di­um cat­a­lysts. When oper­at­ed at low tem­per­a­tures, these cat­a­lysts exhib­it rapid deac­ti­va­tions on stream due to water inhi­bi­tion. In addi­tion, these Pd-cat­a­lysts are sen­si­tive to sul­fur poi­son­ing, even with the pres­ence of a trace amount (≤ 1 ppm) of SO2 in the feed. Among oth­er oxide mate­ri­als, zeo­lites were also inves­ti­gat­ed as a poten­tial sup­port for pal­la­di­um – such as the effects of frame­works and exchange or impreg­na­tion meth­ods – but no sig­nif­i­cant ben­e­fits were dis­cov­ered in the past com­par­ing to con­ven­tion­al alu­mi­na-based cat­a­lysts. Here, we demon­strate the appli­ca­tion of siliceous zeo­lites (i.e. SiO2-to-Al2O3 ratio (SAR) >1200) as Pd-sup­port, the result­ing cat­a­lysts exhib­it sig­nif­i­cant­ly improved activ­i­ty and on-stream dura­bil­i­ty at low tem­per­a­tures, and are able to be regen­er­at­ed from sul­fur poi­son­ing under real­is­tic oper­at­ing con­di­tions.

Biog­ra­phy — Jing Lu received his B.S. degree in Chem­i­cal Engi­neer­ing from Uni­ver­si­ty of Cal­i­for­nia, San­ta Bar­bara. He joined John­son Matthey in 2013 after earn­ing a Ph.D. from Uni­ver­si­ty of Cal­i­for­nia, Davis where he worked with Prof. Bruce Gates. Jing is cur­rent­ly a Staff Sci­en­tist lead­ing the devel­op­ments of selec­tive cat­alyt­ic reduc­tion, ammo­nia slip con­trol and methane oxi­da­tion cat­a­lysts for diesel and nat­ur­al gas aftertreat­ment. He is an inven­tor of sev­er­al patents and author of 19 jour­nal arti­cles.