Effect of MGO additive on preventing leakage of Cr(VI)
by Jin-Chun Chai; Takanori Hino; Satoshi Shimoda; Shuilong Shen
International Journal of Environment and Waste Management (IJEWM), Vol. 15, No. 1, 2015

Abstract: The effect of a new additive, oxide magnesium (MgO), on preventing or reducing the leakage of Cr(VI) from a fly ash (coal ash) has been investigated by batch contact and column percolation tests. The test results indirectly indicate that the MgO additive has an obvious effect on reducing Cr(VI) to Cr(III), which is less environmentally hazardous. However, the process of reducing Cr(VI) to Cr(III) may be reversible because adding H₂SO₄ or CaH₂O₂ into the balanced solid-liquid mixture for partially simulating possible environmental change increased Cr(VI) concentration in the liquid phase. Adding 10% to 30% of Ariake clay into the fly ash not only further reduced Cr(VI) concentration, but also reduced total Cr concentration. Hence, Cr(III) ions may be absorbed by the clay minerals. For the conditions investigated, the column percolation test resulted in higher initial Cr(VI) concentration in the liquid phase than that of the batch contact test. Further, the results of the column percolation test using the samples with different curing time (up to three weeks) indicate that with MgO additive, curing the sample does not have an obvious effect on Cr(VI) concentration.

Online publication date: Sat, 09-May-2015

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

 
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Environment and Waste Management (IJEWM):
Login with your Inderscience username and password:

Username:        Password:          Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com