Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University, Nanchang 330063, China.
School of Engineering and Built Environment, Griffith University, Nathan, QLD 4111, Australia.
Molecules. 2021 Dec 22;27(1):54. doi: 10.3390/molecules27010054.
The removal of boron (B) from water by co-precipitation with hydroxyapatite (HAP) has been extensively studied due to its low cost, ease of use and high efficiency. However, there is no explicit mechanism to express how resolved B was trapped by HAP. Thus, in this work, the process of removing B from water was studied using a low-cost calcium (Ca) precipitation agent derived from used waste oyster shells. The results showed that the removal rate of B in the simulated wastewater by calcined oyster shell (COS) in the presence of phosphorus (P) is up to more than 90%, as opposed to virtually no removal without phosphate. For B removal, the treated water needs to be an alkaline solution with a high pH above 12, where B is removed as [CaB(OH)] but is not molecular. Finally, the synergistic mechanism of co-precipitation between HAP and dissolved B, occlusion co-precipitation, was explained in detail. The proposed method discovered the relationship between Ca, P and B, and was aimed at removing B without secondary pollution through co-precipitation.
由于成本低、使用方便、效率高，水合羟基磷灰石（HAP）共沉淀法去除硼（B）已得到广泛研究。然而，目前还没有明确的机制来表达被 HAP 捕获的硼（B）是如何被固定的。因此，在这项工作中，使用来源于废弃牡蛎壳的低成本钙（Ca）沉淀剂研究了从水中去除 B 的过程。结果表明，在有磷（P）存在的情况下，煅烧牡蛎壳（COS）在模拟废水中对 B 的去除率高达 90%以上，而没有磷酸盐的情况下几乎没有去除。对于 B 的去除，处理后的水需要是碱性溶液，pH 值高于 12，其中 B 作为[CaB(OH)]被去除，但不是分子态。最后，详细解释了 HAP 和溶解的 B 之间共沉淀的协同机制，包裹共沉淀。该方法发现了 Ca、P 和 B 之间的关系，旨在通过共沉淀去除 B，而不会造成二次污染。
