This paper aims to briefly overview gasification technologies of biomass and heterogeneous wastes as a means for syngas production. For this purpose, an overview of the existing technologies, their main advantages, limitations, and costs, as well as commercial plants and projects (lower TRL) operating with these technologies and syngas applications is presented. The type of technology and operating parameters should be selected considering the quality of the syngas as it will dictate its end use. Syngas quality is determined by the combination of feedstock properties, type of technology and process operating conditions, and the scale of operation. For smaller projects with a capacity of up to 10 MWth, fixed-bed technologies have been a recurring choice, while fluidized bed reactors can have an installed capacity above 100 MWth and are, therefore, more suitable for medium- and large-scale projects. Fluidized bed gasification technology supports feedstock flexibility, has scale-up potential, and presents relatively low cost, making it a suitable solution and a frequent choice for heterogeneous waste gasification in medium- or large-scale projects. Commercializing waste gasification technology is already a reality. However, more efforts need to be made so that pilot and demonstration projects can overcome the technological and economic problems and move towards commercialization.

The cultivation of energy crops on degraded soils contributes to reduce the risks associated with land use change, and the biomass may represent an additional revenue as a feedstock for bioenergy. Switchgrass and giant reed were tested under 300 and 600 mg Cr kg⁻¹, 110 and 220 mg Ni kg⁻¹, and 4 and 8 mg Cd kg⁻¹ contaminated soils, in a two year pot experiment. Switchgrass yields (average aerial 330 g.m⁻² and below ground 430 g.m⁻²), after the second year harvest, were not affected by Cd contamination and 110 mg Ni kg⁻¹, but 220 mg Ni kg⁻¹ significantly affected the yields (55–60% reduction). A total plant loss was observed in Cr-contaminated pots. Giant reed aboveground yields (control: 410 g.m⁻²), in the second year harvest, were significantly affected by all metals and levels of contamination (30–70% reduction), except in 110 mg Ni kg⁻¹ pots. The belowground biomass yields (average 1600 g.m⁻²) were not affected by the tested metals. Contamination did not affect the high heating value (HHV) of switchgrass (average 18.4 MJ.kg⁻¹) and giant reed aerial fractions (average 18.9 MJ.kg⁻¹, stems, and 18.1 MJ.kg⁻¹, leaves), harvested in the second year, indicating that the biomass can be exploited for bioenergy.

Lignocellulosic biomass has been widely investigated as a natural renewable source of feedstocks to produce high value added products which can replace energy and materials obtained from non-renewable sources. Polymers are products largely employed in industry in many different applications, which nowadays are mostly produced from petrochemical derivatives, generating huge amounts of waste of difficult treatment prior to disposal. In order to replace these polymers derived from petroleum, efforts have been made in the development of biopolymers, in the biorefinery context, derived from biomass possessing physicochemical properties similar to those derived from petroleum so that they can successfully replace these materials. A review on the different types of biopolymers obtained from biomass, as polysaccharides, lipids, proteins, polyesters produced by plants and microorganisms, and other assorted biopolymers is accomplished. An evaluation of physicochemical properties and applications of different types of biopolymers is approached. It is also discussed about the degradability of biopolymers differentiating oxo-degradability and biodegradability. A brief historic background about biopolymers is also exposed.

The dwindling availability of agricultural land, caused by factors such as rapid population growth, urban expansion, and soil contamination, has significantly increased the pressure on food production. To address this challenge, cultivating non-food crops on contaminated land has emerged as a promising solution. This approach not only frees up fertile soil for food production but also mitigates human exposure to contaminants. This work aimed to examine the impact of soil contamination with Cd, Pb, Ni, and Zn on the growth, productivity, metal accumulation, and the tolerance of five lignocellulosic non-food crops: switchgrass (Panicum virgatum L.), biomass sorghum (Sorghum bicolor L. Moench), giant reed (Arundo donax L.), African fodder cane (Saccharum spontaneum L. spp. aegyptiacum Willd. Hackel), and miscanthus (Miscanthus × giganteus Greef et Deu.). A two-year pot experiment was conducted in Greece, Italy, and Portugal, following the same protocols and applying various levels of metals: Cd (0, 4, 8 mg kg⁻¹), Pb and Zn (0, 450, 900 mg kg⁻¹), and Ni (0, 110, 220 mg kg⁻¹). The experimental design was completely randomized, with three replicates for each treatment. The results showed that switchgrass and sorghum generally maintained their height and productivity under Cd and Pb stress but were adversely affected by high Zn and Ni concentrations. Giant reed and African fodder cane showed reduced height and productivity at higher Ni and Zn levels. Miscanthus exhibited resilience in height but experienced productivity reductions only at the highest Zn concentration. Heavy metal uptake varied among crops, with switchgrass and sorghum showing high Cd and Pb uptake, while giant reed accumulated the most Cd and Zn. Miscanthus had the highest Ni accumulation. The tolerance indices indicated that switchgrass and sorghum were more tolerant to Cd and Zn at lower concentrations, whereas miscanthus had lower tolerance to Cd but a higher tolerance to Zn at higher concentrations. Giant reed and African fodder cane demonstrated stable tolerance across most heavy metals. Accumulation indices highlighted the effectiveness of switchgrass and sorghum in Cd and Pb uptake, while miscanthus excelled in Ni and Zn accumulation. The cluster analysis revealed similar responses to heavy metal stress between African fodder cane and giant reed, as well as between sorghum and miscanthus, with switchgrass displaying distinct behavior. Overall, the study highlights the differential tolerance and accumulation capacities of these crops, indicating the potential for phytoremediation applications and biomass production in heavy metal-contaminated soils.

The overuse of nonrenewable resources has motivated intensive research and the development of new types of green bio-based and degradable feedstocks derived from natural sources, such as cellulose derivates, also in nanoforms. The inclusion of such nanoparticles in bio-based polymers with the aim of providing reinforcement is a trend, which, when associated with the incorporation active compounds, creates active packaging suitable for the packaging of highly perishable food, thus contributing to the product’s shelf-life extension. Chitosan (Ch)/sage essential oil (SEO) bionanocomposite reinforced with nanocrystalline cellulose (CNC) was cast as active packaging for the preservation of fresh poultry meat. Meat samples were wrapped in different bioplastics (pristine chitosan, chitosan with commercial CNC, chitosan with CNC obtained from three different lignocellulosic crops, giant reed (G), kenaf (K), and miscanthus (M), chitosan with SEO, and chitosan with SEO and CNC), while unwrapped samples were tested as the control. Periodically, samples were evaluated in terms of their physicochemical properties and microbial growth. Additionally, bionanocomposites were also evaluated in terms of their in situ antimicrobial properties, as well as migration toward food simulants. Meat samples protected with bionanocomposites showed lower levels of microbiological growth (2–3 logs lower than control) and lipid oxidation (20–30% lower than in control), over time. This was attributed to the intrinsic antimicrobial capacity of chitosan and the high oxygen barrier properties of the films resulting from the CNC inclusion. The SEO incorporation did not significantly improve the material’s antimicrobial and antioxidant activity yet interfered directly with the meat’s color as it migrated to its surface. In the in vitro assays, all bionanocomposites demonstrated good antimicrobial activity against B. cereus (reduction of ~8.2 log) and Salmonella Choleraesuis (reduction of ~5–6 log). Through the in vitro migration assay, it was verified that the SEO release rate of phenolic compounds to ethanol 50% (dairy products simulate) was higher than to ethanol 95% (fatty food simulate). Furthermore, these migration tests proved that nanocellulose was capable of delaying SEO migration, thus reducing the negative effect on the meat’s color and the pro-oxidant activity recorded in TBARS. It was concluded that the tested chitosan/nanocellulose bionanocomposites increased the shelf life of fresh poultry meat.