Esterification of stearic acid using novel protonated and crosslinked amidoximated polyacrylonitrile ion exchange fibres

Date

2023-01-23

Advisors

Journal Title

Journal ISSN

ISSN

1226-086X

Volume Title

Publisher

Elsevier

Type

Article

Peer reviewed

Yes

Abstract

This study will demonstrate the conversion of stearic acid to methyl stearate (biodiesel) using for the first time crosslinked amidoximated polyacrylonitrile ion-exchanged mesh protonated by sulphuric acid. Quantitative analysis of conversion was by GC-FID, 1H NMR and ATR-FT-IR with GC-FID the most reliable. A molar ratio of methanol to stearic acid of 35.5: 1 gave 94 % conversion to the ester at 90 C. At 65 C and a greater ratio of 87.1:1 conversion was 94.1 % comparable to the 98 % yield obtained with 1wt% H2SO4. Re-use at 65 C gently dropped to 57 % on the 13th cycle. Regeneration by washing with dichloromethane and re-acidification achieved 84 % conversion but quickly deactivated due to blocking of sites by methyl stearate as shown by ATR-FTIR. This protonated amidoxime PAN catalyst (distinct from sulfonated fibres) exhibited higher stability than other heterogeneous protonated catalysts (ion-exchange resins, zeolites, clays) used lower temperatures and shorter reaction times. Advantages of using a mesh in place of powders are its ease of removal/replacement for continuous flow reactors promoting quick changes in process parameters. This study is promising as providing a sustainable protonated catalyst for use in converting Fats, Oils and Greases (FOG’s) in waste oils and wastewater to biodiesel. 2022 The Authors. Published by Elsevier B.V. on behalf of The Korean Society of Industrial and Engineering Chemistry. This is an open access article under the CC BY-NC-ND license

Description

open access article

Keywords

Fats Oil and Greases (FOGs), Free fatty acids (FFAs), Esterification reaction, Methyl ester, Amidoxime modified Polyacrylonitrile

Citation

Ahmed, R., Rashid, S. and Huddersman, K. (2023) Esterification of stearic acid using novel protonated and crosslinked amidoximated polyacrylonitrile ion exchange fibres. Journal of Industrial Engineering Chemistry, 119, pp. 550-573

Rights

Research Institute