XPS光谱表明，HAP-CS复合物吸附CR导致在P 2P，Ca2P和O 1s峰上更高的能量转变，从346.7，132.9和530.5 eV转变到347.1，133.2和530.7 eV(Fig.9)。因此，它可能表明，HAP-CS复合物和CR染料之间可能的相互作用，相互作用位点应该是Ca和PO
2+
3-4和
OH。
-
结合XPS和FT-IR的结果可以推断出应该存在于HAP-CS复合物中的Ca和CR染料中的-NH2基团。此外，染料吸附后HAP-CS复合物表面的Ca/P比率从1.35上升到1.48（由XPS和ICP-OES分析），这也印证了PO
3-PO42+
确实涉及在吸附过程中，可能是因为HAP-CS复合物中的
3-之
3-4和
CR染料中的-SO间的离子转换[38]。在关于OH相互作用位
-
点，应归因于复合物的-OH和CR染料-NH2之间的氢键。
从上述讨论中可以得出这样的结论，除了静电相互作用，HAp-CR复合物吸附CR染料可能的吸附机理应该包括表面络合作用，离子交换和氢键。
4。结论
综上所述，，根据制备的把Hap包埋到CS中是一种很有前途的去除CR的吸附剂。通过共沉淀方法合成HAP-CS复合物。CR的重量含量为50％的HAP-CS复合物表现出对CR的最高的吸附能力（769mgg）。动力学和等温线的研究表明，伪二阶模型和Langmuir模型能很好地描述吸附行为。热力学研究表明，HAP-CS复合物对CR的吸附是一个自发的过程。FT-IR和XPS分析表明，除静电作用外，表面络合作用，离子交换和氢键也可能参与HAP-CS复合物对CR的吸附。HAP-CS复合物是一种对CR有效的，低成本的吸附剂，预计在染料污染的水净化方面将有一个光明的未来。
致谢
这项工作是由中国四川省基础研究发展计划和中国国家科学基金会（21145002）提供资金支持（2011JY0016）。作者还感谢四川大学分析测试中心的侯先登教授给他提供了宝贵的评论和积极的讨论。
附录A.补充材料
与本文相关的补充数据，在网上的版本可以发现，http://dx.doi.org/10.1016/j.cej.2012.09.100
-1
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