Impact of Hydrofluoric (HF) Acid Treatment on Morphological and Chemical Structure of Agricultural Wastes

Muhammad Amir Javed; Naveed Ramzan; Umair Aslam; Hina Mukhtar; Iftikhar Hussain; Abdul Zahir

Authors

Muhammad Amir Javed Department of Chemical Engineering, University of Engineering and Technology Lahore, Pakistan Author
Naveed Ramzan Department of Chemical Engineering, University of Engineering and Technology Lahore, Pakistan Author
Umair Aslam Department of Chemical Engineering, University of Engineering and Technology Lahore, Pakistan Author
Hina Mukhtar Department of Chemical Engineering, NFC Institute of Engineering and Fertilizer Research, Pakistan Author
Iftikhar Hussain School of Chemical Engineering, Yeungnam University, Republic of Korea Author
Abdul Zahir School of Engineering and Technology, Curtin University, Malaysia Author

Keywords:

biomasses, acidic pretreatment, ash contents, morphology, aromaticity

Abstract

Acid, base and/or water treatments expand biomass utilisation by reducing ash contents and improving energy density and higher heating values. Dilute acid treatment results in negative impacts on the physiochemical structure of biomass. This study aimed to analyse the effects of hydrofluoric (HF) acid (5% w/w) on the morphological and chemical structure of Wheat Straw (WS), Cotton Stalk (CS) and Rice Husk (RH). Scanning Electron Microscopy (SEM) exposed physical changes after treatment, and Fourier Transform Infrared (FTIR) spectroscopy was used to evaluate the changes in available functional groups in the composition of biomass samples. Dilute HF resulted in pronounced changes in morphology and chemical functional groups of all biomasses. Proximate analysis showed carbonaceous material is also affected; the increment in volatiles (9.27%, 7.7% and 6.9% for RH, WS and CS, respectively) and fixed carbon was observed while ash contents reduced. Furthermore, the influence of all samples on the thermal processing of biomass is compared.