Authors : Ashok Agarwal

Volume/Issue : Volume 11 - 2026, Issue 7 - July

Google Scholar : https://tinyurl.com/y55z5n6f

Scribd : https://tinyurl.com/yrucj75a

DOI : https://doi.org/10.38124/ijisrt/26jul1834

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Abstract : Spent Bleaching Earth (SBE) is a by-product generated during the refining of edible oils using activated bleaching clay. Depending on refinery operating conditions, SBE typically contains between 30 and 50 % entrained vegetable oil [1,2]. The residual oil retained within the porous clay structure represents a significant economic loss while simultaneously creating handling, storage, and environmental challenges. Recovery of the entrained oil followed by regeneration of the clay offers a sustainable approach to waste minimization and resource recovery [3,4]. This paper discusses the extraction of retained oil from SBE using solvent extraction technology and the subsequent regeneration of the de-oiled clay through thermal treatment and acid activation to produce regenerated bleaching earth suitable for reuse in edible oil refining operations.

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