Solid acid catalyst development from rubber tire waste for biofuel and biochemical production

A rubber tire is a thermoset polymer that is flexible and connected by 3D framework from vulcanization. The growth of vehicle industries increases the demand for rubber tires, resulting in high rubber tire waste affecting the environment. Utilization of rubber tire waste is one of the methods to reduce environmental concerns as follows as Bio-Circular-Green-Economy (BCG). For example, recycling rubber tire waste for new products, use of rubber tire waste as a heating source, and pyrolysis of rubber tire waste for fuels. Although these methods seem promising, the use of rubber tire waste to new products leads to a drop in physical properties and burning rubber tire waste to generate heat causes air pollution.

    From the concerns above, many researchers have developed a way to utilize rubber tires in a new applications such as catalysts and adsorbents. To synthesize a rubber tire as a solid acid catalyst, the rubber tire is pyrolyzed at a high temperature to convert rubber tires to carbon. Then, the resulting carbon will be developed further into catalysts or adsorbents. Although this method seems promising, the process is complex and involves pyrolysis, leading to high energy consumption.

    This research aims to study the solid acid catalyst synthesis from rubber tire waste using an uncomplex method and low energy consumption by sulfonation reaction of rubber tire. The degree of sulfonation will be studied in this research to obtain different sulfonate group concentrations on rubber tire surfaces affecting physical and chemical properties. The resulting catalysts will be tested the efficiency and catalyst stability (after recycling) using esterification of levulinic acid and methanol as a probe reaction against a commercial solid acid catalyst (Amberlyst).

    This research aims to produce solid acid catalysts from rubber tire waste using an uncomplex method and low energy consumption, which have high catalytic efficiency and recycling stability equal/better than a commercial catalyst (Amberlyst). We hope that this research will make rubber tire waste to wealth and compatible with industries.