Novel configurations for a citrus waste based biorefinery: from solventless to simultaneous ultrasound and microwave assisted extraction

Abstract

Innovative extraction configurations for the biorefining of a biomass waste (citrus peel) were developed in this work. Nonconventional energies, such as microwaves (MW) and ultrasounds (US), were directly irradiated to the fresh orange peel using a versatile MW coaxial dipole antenna. This particular MW configuration enabled us to build two new extraction systems: 1) a coaxial solventless MW-assisted extraction approach (SMWAE) and, 2) a simultaneous ultrasound coaxial MW-assisted hydrodistillation (US-MWHD). The yield and chemical composition of the essential oils of the orange peel obtained by the two innovative approaches were analyzed as a function of the extraction time and compared with the coaxial microwave hydrodistillation (MWHD) and conventional hydrodistillation (CH). The EOs were chemically characterized by GC and GC-MS analysis. The residue mash was then used to extract pectin by a MW-assisted procedure. Structure and thermal stability of the pectin were investigated by FTIR and TG. The biorefining of EOs and pectin from a citrus waste maximise the benefits of our proposed green methodologies, which involve safe operability, faster processing and easy scalability. Furthermore, the energy consumed per unit mass of products in each step of the orange peel biorefining clearly showed that the most promising approach is the SMWAE (since it is around around 27 times lower than the CH approach). The MWHD and US-MWHD also showed more than 60% energy savings compared to the CH

Recent advances in orange oil extraction: an opportunity for the valorisation of orange peel waste a review

“…In addition, further research may explore the advantages and disadvantages of possible combined techniques for the extraction of essential oils, similar to the methodology that described by González‐Rivera et al . ().…”

“…As an example, to get benefits from the combined advanced techniques, González‐Rivera et al . () designed and developed an innovative system for the extraction of essential oils from orange peel which integrated microwave and ultrasound processes. The designed equipment were run in two different modes, namely coaxial solvent‐free MAE and simultaneous ultrasound coaxial microwave‐assisted hydrodistillation.…”

Thermal analysis of some novel pyrimidine derivatives

“…Thermal analysis has been used to determine the physical and chemical properties of various types of materials [1][2][3][4][5][6]. Scientific and technological achievements together with demands based on industrial requirement have permitted the development of various types of materials that can withstand at much higher temperatures and more corrosive environments.…”

Fast and Eco–friendly Microwave‐Assisted Synthesis of Silver Nanoparticles using Rosemary Essential Oil as Renewable Reducing Agent.

“…The coaxial dipole antenna can be used not only to assist MW reactions but also to assist separation operation units such as the in‐situ MW assisted hydrodistillation of essential oils from different plants and feedstock …”