Valorization of the biomass of Rhizoclonium hookeri through slow pyrolysis and its thermokinetic investigation for bioenergy potential. (January 2023)

• Record Type: Journal Article
• Authors: Iqbal, Arshad; Noreen, Noreen; Imran, Muhammad; Francisco Alves, José Luiz; da Silva, Jean Constantino Gomes; Badshah, Syed Lal
• Is Part Of: Biomass and bioenergy. Volume 168(2023)
• Publication Date: 2023-01
• Subjects: Macroalgae biomass -- Pyrolysis -- Thermogravimetric analysis -- Bioenergy -- Activation energy; Biomass energy -- Periodicals; Biomass -- Periodicals; Energy-Generating Resources -- Periodicals; Bioénergie -- Périodiques; 333.9539
• DOI: 10.1016/j.biombioe.2022.106690
• Languages: English
• ISSNs: 0961-9534

Abstract

Abstract: The macroalgae, Rhizoclonium hookeri has the ability to grow in fresh and wastewater rich in nutrients like phosphorus and nitrogen. Here we have performed the slow pyrolysis of dried R. hookeri at three different thermal rates of 5, 10 and 20 ° C min −1 from 25 to 800 ° C using the thermogravimetric technique to get the thermokinetics for its bioenergy value. Four different thermal degradation stages were considered to get the kinetic triplets from its pyrolysis. The activation energy was obtained for each stage of thermal decomposition utilizing four classical isoconversional methods (Friedman, Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, and Starink). The activation energies obtained through these isoconversional methods for the four valorization zones of R. hookeri were in the range of 151.15–192.62 kJ mol −1 . The pre-exponential factor ( A ) showing the chemical nature of each reaction step was extracted from the kinetic compensation effect and has values in the range of 1.99 × 10 20 to 2.63 × 10 12 min −1 . The thermodynamic parameters revealed the non-spontaneous, endothermic and complex nature of the pyrolysis process of Rhizoclonium biomass. The thermokinetic data showed that Rhizoclonium biomass has bioenergy potential like other macroalgae and is a suitable feedstock for the large-scale pyrolysis process. In conclusion, the outcomes from this study suggest the suitability of Rhizoclonium hookeri as a feedstock for producing bioenergy and is of great significance for designing large-scale equipment to pyrolyze this macroalgal specie. Highlights: First detailed investigation on the bioenergy potential of Rhizoclonium hookeri. Pyrolysis of Rhizoclonium is assumed to follow four thermal decomposition stages. Average E a of the biomass pyrolysis ranges from 151.1 to 192.6 kJ mol −1 . Pyrolysis of Rhizoclonium was endothermic and non-spontaneous in nature. Rhizoclonium can be considered an attractive feedstock for bioenergy production.