Kapa ʻia ka poepoe pālolo porous i nā pōpō kānana. Hana ʻia ia e 20-30% mau pores i loko o nā kinipōpō ceramic. No laila hiki ke hoʻohana ʻia ʻaʻole wale no ke kākoʻo ʻana a me ka uhi ʻana i ka catalyst, akā no ka kānana ʻana a me ka hoʻopau ʻana i nā haumia o ka palaoa, gelatin, asphalting, metala kaumaha a me nā hao hao o lalo o 25um. Inā hoʻonohonoho ʻia ka poepoe porous ma ka piko o kahi reactor, ʻaʻole e hoʻopau ʻia nā impurities i ka hana mua i hiki ke hoʻolaha ʻia i nā pores i loko o nā pōpō, ma laila e pale ai i ka catalist a hoʻolōʻihi i ke kaʻina hana o ka ʻōnaehana. E like me nā ʻokoʻa i loaʻa i nā mea like ʻole, hiki i ka mea hoʻohana ke koho i ka huahana e ko lākou nui, nā pores a me ka porosity, a i ʻole inā pono, e hoʻohui i ka molybdenum, nickel a me cobalt a i ʻole nā mea hana ʻē aʻe e pale ai i ka catalyst mai ka coking a me ka lāʻau make.