Cat litter and preparation method thereof

The invention relates to cat litter which is of a multi-layer core-shell structure and comprises an inner core, an inner shell and a filling shell. The inner core comprises the following raw materials in parts by weight: 10-15 parts of diatomite, 30-45 parts of volcanic rock, 3-6 parts of a bacteriostatic agent and 10-15 parts of a first adhesive; the inner shell comprises the following raw materials in parts by weight: 15-20 parts of wood chips, 3-6 parts of a second adhesive, 20-25 parts of bamboo fibers and 6-10 parts of activated aluminum oxide powder; the filling shell comprises the following raw materials in parts by weight: 5-10 parts of white carbon black, 3-5 parts of a foaming agent, 1-3 parts of natural perfume, 10-15 parts of montmorillonite powder, 10-20 parts of pea fiber and 15-25 parts of puffed corn flour; the filling shell is of a porous structure, the porous structure is filled with a color developing mixing agent, and the filling shell is coated with a water-soluble film. Through the arran