Premium
Low‐temperature conversion of spent adsorbent to iodine sodalite by a mechanochemical route
Author(s) -
Hirabayashi D.,
Tanada Y.,
Sugiyama T.,
Enokida Y.,
Sawada K.
Publication year - 2012
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.12756
Subject(s) - sodalite , zeolite , leaching (pedology) , ball mill , iodine , sodium aluminate , materials science , adsorption , chemical engineering , crystallization , nuclear chemistry , chemistry , mineralogy , inorganic chemistry , metallurgy , catalysis , aluminium , organic chemistry , environmental science , soil science , engineering , soil water
Abstract The focus on a ball milling induced conversion as a possible synthesis route of iodine sodalite (Na 8 Al 6 Si 6 O 24 I 2 ) from zeolite‐based iodine adsorbents in order to treat a radioactive iodine filter for the off‐gas cleaning during nuclear facilities is presented. A mixture of silver iodide and zeolite 13X as a simulated adsorbent was mechanochemically milled using a laboratory‐scale planetary ball mill. The obtained powders were characterized by X‐ray diffraction to determine the effect of milling time on the conversion of the iodine sodalite. The crystal grain size and the lattice strain of the grounded phases were evaluated. After the ball milling, the milled samples were hydrothermally crystallized to form a sodalite phase with a sodium hydroxide solution for 48 h in an autoclave maintained at 150 ° C. The iodine sodalite was successfully obtained after hydrothermal crystallization. A leaching test was carried out for the assessment of the order of iodine leachability and chemical durability under reducing conditions. The leaching amount was found to be low on the orders of 10 −4 ∼10 −5 mol dm −3 in sodium thiosulfate solution. © 2011 American Institute of Chemical Engineers AIChE J, 58: 2441–2447, 2012