Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6308657 | Chemosphere | 2014 | 6 Pages |
Abstract
Chemical oxo-precipitation (COP), which combines treatment with an oxidant and precipitation using metal salts, was developed for treating boron-containing water under milder conditions (room temperature, pH 10) than those of conventional coagulation processes. The concentration of boron compounds was 1000Â mg-BÂ Lâ1. They included boric acid (H3BO3) and perborate (NaBO3). Precipitation using calcium chloride eliminated 80% of the boron from the perborate solution, but was unable to treat boric acid. COP uses hydrogen peroxide (H2O2) to pretreat boric acid, substantially increasing the removal of boron from boric acid solution by chemical precipitation from less than 5% to 80%. Furthermore, of alkaline earth metals, barium ions are the most efficient precipitant, and can increase the 80% boron removal to 98.5% at [H2O2]/[B] and [Ba]/[B] molar ratios of 2 and 1, respectively. The residual boron in the end water of COP contained 15Â ppm-B: this value cannot be achieved using conventional coagulation processes.
Related Topics
Life Sciences
Environmental Science
Environmental Chemistry
Authors
Yu-Jen Shih, Chia-Hsun Liu, Wei-Cheng Lan, Yao-Hui Huang,