Molecular NO(2) induced K(2)Ti(2)O(5)-K(2)Ti(6)O(13) structure switching in the dry gas phase: lattice potassium reactivity.

A very interesting structure switching phenomenon between K(2)Ti(2)O(5) and K(2)Ti(6)O(13) caused by gas phase molecular NO(2) adsorption and desorption at 500-600 degrees C is revealed, during which NO(2) is adsorbed on the lattice K(+) ion sites to form KNO(3) and the loss of K causes the remainder to regroup into nano-sized K(2)Ti(6)O(13), with a lower K/Ti value.

[Treatment of landfill leachate using sequential anaerobic/aerobic moving-bed biofilm reactor].

A sequential anaerobic-aerobic moving-bed biofilm reactor (MBBR) was employed to treat landfill leachate produced from disposal of municipal solid waste. The affecting operation conditions were investigated, and the affecting mechanism was also analyzed. The results showed that the HRT and organic loading rate (OLR) could greatly influence the treat efficiency.