POMEGRANATE PEEL AS AN EFFECTIVE ADSORBENT FOR FURFURAL EXTRACTION FROM AQUEOUS SOLUTIONS

Abstract

Investigations to study the adsorption of furfural from aqueous solutions with sorbents obtained on the basis of pomegranate peel are going on. It has been shown that pomegranate peel treated with pyrophosphoric acid (modified), and the peel treated with phosphoric acid hase the same adsorption capacity.. The use of the pyrophosphoric acid is explained by the fact that, in an aqueous environment, the previously used phosphoric (orthophosphoric) acid is partially converted into pyrophosphoric acid. It has been suggested that pyrophosphoric acid in aqueous solutions when processing a pomegranate peel exhibits the same properties as phosphoric acid.

A pomegranate peel is an important cleaning agent for crude oil to remove a number of undesirable substances. Furfural is also used in petrochemical plants as a solvent for the extraction of dienes from a mixture of hydrocarbons. Purification of furfural from aqueous solutions is important for removing this rather toxic substance from the ecosystem, since it is currently widely used to obtain solid resins by the reaction with phenol and acetone, or with urea.

The content of furfural in aqueous solutions before and after adsorption purification is carried out using ultraviolet (UV) spectrophotometry in the region of 290…295 nm, as well as a high-performance liquid chromatograph (HPLC). It has been established that the process of furfural adsorption by a biosorbent - crushed pomegranate peel - is described by the Langmuir isotherm equation. The use of a modified pomegranate peel minimizes the economic and environmental risks compared to the production of activated carbon from the same peel.

It has been shown that the modified pomegranate peel has an adsorption activity approximately twice as high as activated carbon from the same peel.