The intercalation of kaolinite through the insertion of ions or molecules amongst the structural aluminosilicate layers is a vital process in numerous clay-based applications and products. Layer neutrality and hydrogen bonding limits direct intercalation into kaolinite, other than for small molecules. Synthesizing zirconia-intercalated kaolinite is not a straightforward matter. To overcome this barrier, raw Egyptian kaolin (UnK) or its acid-activated product (HK) was sonicated and impregnated in aqueous ZrOCl₂·8H₂O solution followed by thermal treatment at various temperatures (100, 200, 300, and 500°C). The intercalation process was confirmed using various spectroscopic and analytical techniques. The direct intercalation of ZrO₂ into the kaolinite layers was observed even through a mild thermal treatment (100, 200, and 300°C). The mechanism of intercalation was suggested to occur by binding ZrO₂ to the Si/AlO groups with a preference for the acid-activated HK, causing variable enlargements of the basal spacing and producing very perturbed layers. Interestingly, the surface area increased by 250% as a result of zirconia intercalation. Scanning electron microscopy (SEM) images showed a remarkable improvement in the stacking order of the kaolinite particles. The impact of ZrO₂ intercalation into kaolinite also enhanced its adsorption efficiency for Pb²⁺, Cu²⁺, and Cd²⁺ ions. Preliminary investigations showed that the zirconia-intercalated HK demonstrated a removal efficiency, which is three times greater than that of pristine HK. The adsorption tendency toward Pb²⁺ ions was greater than those of Cu²⁺ and Cd²⁺ and followed the order: Pb²⁺ >> Cu²⁺ > Cd²⁺. The study suggests that the chemical modification of kaolin by zirconia via a direct intercalation technique, which greatly improves its functionality as demonstrated by the selective sorption of heavy metal ions, is worthy of further study.

通过在结构铝硅酸盐层之间插入离子或分子来插入高岭石是许多基于粘土的应用和产品的重要过程。除小分子外，层中性和氢键限制了直接嵌入高岭石中。合成氧化锆插层高岭石并不是一件简单的事情。为了克服这一障碍，将埃及高岭土 (UnK) 或其酸活化产品 (HK) 超声处理并浸渍在 ZrOCl ₂ ·8H ₂ O 水溶液中，然后在不同温度（100、200、300 和 500° C）。使用各种光谱和分析技术证实了嵌入过程。ZrO ₂的直接嵌入即使通过温和的热处理（100、200 和 300°C），也可以观察到高岭石层中的渗碳现象。嵌入的机制被认为是通过将 ZrO ₂结合到 Si/AlO 基团而发生的，优先选择酸活化的 HK，导致基础间距的可变扩大并产生非常扰动的层。有趣的是，由于氧化锆嵌入，表面积增加了 250%。扫描电子显微镜 (SEM) 图像显示高岭石颗粒的堆积顺序显着改善。ZrO ₂嵌入高岭石的影响也提高了其对 Pb ²⁺、Cu ²⁺和 Cd ^{2+ 的}吸附效率离子。初步调查表明，插入氧化锆的 HK 表现出去除效率，是原始 HK 的三倍。对Pb ²⁺离子的吸附趋势大于Cu ²⁺和Cd ^{2+ ，}并遵循以下顺序：Pb ²⁺ >> Cu ²⁺ > Cd ²⁺。该研究表明，氧化锆通过直接嵌入技术对高岭土进行化学改性，如重金属离子的选择性吸附所证明的那样，大大提高了其功能，值得进一步研究。