CHARACTERIZATION OF SPONGE-GOURD RESIDUE PRETREATED BY MECHANICAL DISC REFINING

Abstract

The present works describes the effect produced by mechanical disc refining in the pretreatment of lignocellulose agro-industrial waste, using scraps of sponge gourd. Two batches of sponge gourd scraps were refined in a laboratory disc refiner, at a consistence of 2.9 wt% (fiber/water) and residence time of 2 and 4 min. The two batches were then coded as MRS and HRS, respectively. MRS and HRS samples, as well as non-refined sponge gourd (NRS), were characterized in terms of morphological aspects, structural characteristics and thermal behavior. The analysis of SEM micrographs revealed that internal fibrillation dominated the refining process of sponge gourd, which, consequently, led to an increased surface area of the fibers. It was observed that the use of the disc refiner promoted the extraction of some hemicellulose content, increased the devolatilization index to 70% and 60%, as well as crystallinity – to 22% and 31% for MRS and HRS, respectively.