TY - JOUR
T1 - Rapid Ti(III) reduction of perchlorate in the presence of β-alanine
T2 - Kinetics, pH effect, complex formation, and β-alanine effect
AU - Wang, Chao
AU - Huang, Zhengdao
AU - Lippincott, Lee
AU - Meng, Xiaoguang
PY - 2010/3/15
Y1 - 2010/3/15
N2 - Ti(III) reduction of perchlorate might be a useful method for the treatment of highly perchlorate-contaminated water. Though the reaction rate was usually low, we observed that β-alanine (HOOCCH2CH2NH2) could significantly promote the reaction. A complete (>99.9%) perchlorate removal was obtained in a solution containing [ClO4-] = 1.0 mM, [Ti(III)] = 40 mM, and [β-alanine] = 120 mM after 2.5 h of reaction under 50 °C. The effects of both pH and complex formation on the reaction were then studied. The results showed that without β-alanine the optimal pH was 2.3. When pH increased from 1.6 to 2.3, the reduction rate increased remarkably. In the pH range >2.3, however, the reduction was significantly inhibited, attributed to the formation of Ti(III) precipitate. The presence of β-alanine at a molar ratio of [β-alanine]:[Ti(III)] = 3:1 significantly increased the reduction rate of perchlorate even at near neutral pH. This is because β-alanine formed complexes with Ti(III), which greatly improved the total soluble [Ti(III)] in the pH range between 3.5 and 6. The findings may lead to the development of rapid treatment methods for intermittent and small stream of highly perchlorate-contaminated water, which are resulted from the manufacturing, storage, handling, use and/or disposal of large quantities of perchlorate salts.
AB - Ti(III) reduction of perchlorate might be a useful method for the treatment of highly perchlorate-contaminated water. Though the reaction rate was usually low, we observed that β-alanine (HOOCCH2CH2NH2) could significantly promote the reaction. A complete (>99.9%) perchlorate removal was obtained in a solution containing [ClO4-] = 1.0 mM, [Ti(III)] = 40 mM, and [β-alanine] = 120 mM after 2.5 h of reaction under 50 °C. The effects of both pH and complex formation on the reaction were then studied. The results showed that without β-alanine the optimal pH was 2.3. When pH increased from 1.6 to 2.3, the reduction rate increased remarkably. In the pH range >2.3, however, the reduction was significantly inhibited, attributed to the formation of Ti(III) precipitate. The presence of β-alanine at a molar ratio of [β-alanine]:[Ti(III)] = 3:1 significantly increased the reduction rate of perchlorate even at near neutral pH. This is because β-alanine formed complexes with Ti(III), which greatly improved the total soluble [Ti(III)] in the pH range between 3.5 and 6. The findings may lead to the development of rapid treatment methods for intermittent and small stream of highly perchlorate-contaminated water, which are resulted from the manufacturing, storage, handling, use and/or disposal of large quantities of perchlorate salts.
KW - Complexation
KW - Perchlorate
KW - Ti(III)
KW - β-Alanine
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UR - http://www.scopus.com/inward/citedby.url?scp=72149089860&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2009.09.143
DO - 10.1016/j.jhazmat.2009.09.143
M3 - Article
C2 - 19864064
AN - SCOPUS:72149089860
SN - 0304-3894
VL - 175
SP - 159
EP - 164
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
IS - 1-3
ER -