Effects of repetitive production on the mechanical characteristic and chemical structure of green tea bio-coke

A new type of solid biofuel called bio-coke has been developed, which has the potential to replace the use of coal coke in cupola furnaces. This study aimed to improve the mechanical properties of green tea (GT) bio-coke by implementing repetitive production. The properties of unprocessed GT, the initial production of GT bio-coke (known as GT BIC-1), and its subsequent iterations; the 2nd time GT bio-coke (GT BIC-2) and 3rd time GT biocoke (GT BIC-3) were examined. It was found that repetitive bio-coke improved their mechanical capabilities. The mechanical strength at 700 C known as an essential quality to indicate the permeability of bio-coke in the cupola furnace. In comparison to GT BIC-1 (9.20 +/- 1.38 MPa), GT BIC-2 and GT BIC-3 demonstrated higher mechanical strength at 700 C with values of 14.37 +/- 1.98 and 16.18 +/- 0.50 MPa, respectively. This study also investigates the relationship between the structural transformation and the mechanical characteristics of the biocokes. The enhanced aromatic (ARM) and hydrophobicity (HB) index in GT BIC-2 and GT BIC-3 have influenced their rigidity, high temperature tolerance, and water resistance. This suggests that coal coke substitution using repetitive bio-coke in cupola furnaces could be a viable approach to reduce greenhouse gas (GHG) emissions in the future.