A new type of multistage structure hydrotalcite material: To promote the absorption of chemicals in wet leather processing

A novel ZnZr‐MOF‐LDH was designed and synthesized with Zr‐MOF as template, and subsequently, it was applied to leather tanning. Zr‐MOF and ZnZr‐MOF‐LDH were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), and nitrogen adsorption instrument. The results of SEM and TEM shown that when the mass ratio of Zr‐MOF to zinc nitrate was 1:2, the size of ZnZr‐MOF‐LDH was about 100 nm with surface has obvious convex polyhedral multilevel structure. The FT‐IR and XPS results showed that the ZnZr‐MOF‐LDH with good crystal structure was prepared. The Brunauer–Emmett–Teller (BET) results showed that the specific surface area and pore volume of ZnZr‐MOF‐LDH were higher than those of ZnZr‐LDH. The application results shown that compared with 2% chrome tanning agent tanning, the shrinkage temperature of leather treated by ZnZr‐MOF‐LDH combined with 2% chrome tanning agent tanning was increased from 73.1°C to 92.1°C and the thickening rate was increased from 38.71% to 56.98%. The subsequent wet processing was carried out which showed that adding ZnZr‐MOF‐LDH considered to be a good way to enhance the absorption rate of dyestuff and fatliquor, resulting in an ecological process and more economical. The absorption of chemicals during wet processing of leather improves the properties of green leather and reduces environmental pollution.