Graduate School of Environmental Studies, Tohoku University, Aramaki, Aoba-ku, Sendai, Japan.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2012;47(5):711-7. doi: 10.1080/10934529.2012.660080.
Mg-Al oxide obtained by calcination of NO(3)(-)-intercalated Mg-Al layered double hydroxide (NO(3)•Mg-Al LDH) was used to treat H(2)SO(4), acting as both a neutralizer of the acid and a fixative for SO(4)(2-). The fraction of SO(4)(2-) removed increased with time and with increasing Mg-Al oxide quantity and temperature. The rate of SO(4)(2-) removal followed first-order kinetics with apparent rate constants of 2.0 × 10(-3), 4.4 × 10(-3), and 5.3 × 10(-2) min(-1) at 10, 30, and 60°C, respectively. The apparent activation energy was 52.1 kJ mol(-1), confirming that the SO(4)(2-) removal by Mg-Al oxide proceeded under chemical reaction control. Furthermore, the adsorption isotherm of SO(4)(2-) by Mg-Al oxide obeyed the Langmuir equation. The maximum adsorption amount was 2.0 mmol g(-1), or 4.0 meq g(-1), indicating that Mg-Al oxide has a large capacity for uptake of SO(4)(2-) from H(2)SO(4).
用硝酸根插层镁铝水滑石（NO₃⁻·Mg-Al LDH）经煅烧得到的 Mg-Al 氧化物，可用于处理 H₂SO₄，它既能中和酸，又能固定 SO₄²⁻。SO₄²⁻的去除率随时间、Mg-Al 氧化物用量和温度的增加而增加。SO₄²⁻的去除速率遵循一级动力学，在 10、30 和 60°C 时的表观速率常数分别为 2.0×10⁻³、4.4×10⁻³和 5.3×10⁻² min⁻¹。表观活化能为 52.1 kJ mol⁻¹，证实 SO₄²⁻的去除是由 Mg-Al 氧化物的化学反应控制的。此外，Mg-Al 氧化物对 SO₄²⁻的吸附等温线符合朗缪尔方程。最大吸附量为 2.0 mmol g⁻¹，或 4.0 meq g⁻¹，表明 Mg-Al 氧化物对 H₂SO₄ 中 SO₄²⁻的吸附容量很大。
