Effective Utilisation of Halophyte Biomass from Saline Soils for Biorefinering Processes

Abstract

The salinity of European soil is increasing every year, causing severe economic damage (estimated 1–3 million hectares in the enlarged EU). This study uses the biomass of halophytes—tall fescue (grass) and hemp of the Białobrzeskie variety from saline soils—for bioenergy, second generation biofuels and designing new materials—fillers for polymer composites. In the bioethanol obtaining process, in the first stage, the grass and hemp biomass were pretreated with 1.5% NaOH. Before and after the treatment, the chemical composition was determined and the FTIR spectra and SEM pictures were taken. Then, the process of simultaneous saccharification and fermentation (SSF) was carried out. The concentration of ethanol for both the grass and hemp biomass was approx. 7 g·L−1 (14 g·100 g−1 of raw material). In addition, trials of obtaining green composites with halophyte biomass using polymers (PP) and biopolymers (PLA) as a matrix were performed. The mechanical properties of the composites (tensile and flexural tests) were determined. It was found that the addition of a compatibilizer improved the adhesion at the interface of PP composites with a hemp filler. In conclusion, the grass and hemp biomass were found to be an interesting and promising source to be used for bioethanol and biocomposites production. The use of annually renewable plant biomass from saline soils for biorefinering processes opens up opportunities for the development of a new value chains and new approaches to sustainable agriculture.

Special Issue “Lignocellulosic Biomass II”

“…It was concluded that alkaline pretreatment is the most advantageous method not only because of its glucose yield, but also because it allows an easy lignin regeneration from the spent liquor and the simple recovery of sodium hydroxide, which can be returned to the technological process. Batog et al [6] investigated the use of annually renewable plant biomass from saline soils, namely tall fescue and hemp, for biorefining processes leading to biofuels and novel materials. After alkaline pretreatment and simultaneous saccharification, both tall fescue and hemp resulted in yields of 14 g ethanol per 100 g of raw material.…”

Utilization of Festuca arundinacea Schreb. Biomass with Different Salt Contents for Bioethanol and Biocomposite Production

“…Due to low rainfall, high evaporation, salt-water irrigation, overfertilization and other factors, saline areas are increasing by about 10% per year, and we conducted preliminary research on the use of halophytes in the development of an integrated system for bioremediation of saline soils and biorefinery of their biomass [1,13].…”

Exploring the Potential of Halophyte Biomass for Green Biorefinery Applications

“…The development of biosaline agriculture is crucial in regions with saline soils or scarcity of freshwater, and domestication and cultivation of halophytes have a key role in restoring the marginal land area to agricultural production [35,74]. Halophyte cultivation can yield as much as conventional crops; however, biomass production depends on the optimal salinity of cultivated species [75][76][77].…”

“…The fibre fraction is typically used directly as fodder for ruminants. However, there has been an increasing interest in valorising this fraction for biomaterials, including biocomposites, packaging materials, insulation, and nanocellulose [74,118,121,122].…”

“…The extraction process could also prepare the remaining lignocellulosic biomass for further processing, including potential bioenergy production [94,98,129]. Batog et al [74] tested halophyte biomass for biocomposite production and discussed the potential of halophytes for the production of biomaterials. Dong et al [145] tested biochar, a useful soil amendment, from different halophyte feedstocks and found biochar from Tamarix chinensis suitable to improve soil quality with the minimum adverse effect of increased soil salinity.…”