... old pore-forming material-- refined naphthalene, our product has uniform pores, and it is odorless, non-polluting, easy ... special process have excellent wear resistance, uniform particle size, and ultra-high shell content.Physical and chemical performance indexSpecific ... 8.7%3 [Filter] walnut shellAppearance:shiny ,beautiful, brown. High-quality fruit (coconut, apricot) shell as raw materials, it is ...