Use of marble waste in rubber industry: Part I (in NR compound)

In this study an attempt has been made to utilise marble powder derived from the marble slurry produced by gangsaw machines while cutting marble blocks in the north-west of India. The marble powder has been used; 1) as a cheap filler, 2) as a semi reinforcing filler, by doing chemical treatment of the slurry and 3) as partial replacement of carbon black filler to reduce the cost of the compounds, subsequently for products and also to find suitable disposal of the powder, which is creating a serious threat to the local environment. The methodology in this study is as follows: collection of marble powder and characterisation, evaluation of rubber compound including partial replacement of carbon black filler, treatment of the marble powder to enhance the reinforcing characteristics and evaluation of the product. It was found in this study that the marble powder can be used as a cheap filler, in place of other commercial fillers like whiting. However, no significant improvement was obtained by chemical treatment of the marble powder. Marble powder can also be used as a partial replacement of carbon black (up to 10 phr) in various rubber products, which operate under static conditions.