Kinetics of Heat Regeneration of Spent Bleaching Clay

Abstract

In the present study, heat regeneration of spent bleaching clay was conducted in a box furnace with air flowing through it. The regenerated clay was then employed for bleaching peanut oil. Red color indices of bleached and unbleached peanut oils were determined to calculate regeneration efficiency. Experimental results indicate that the regeneration rate can be increased by increasing the temperature between 573 and 773 K. However, above 773 K, the regeneration rate is reduced due to sintering of the clay. The rate expression for regeneration is determined to be

dRE/dt^* = 0.2177exp(–74, 260/RT)(100 – RE)^2.85

where

t^* = t – t_ind[1 – exp(–t/t_ind)]