Evaluating river driftwood as a feedstock for biochar production.

Driftwood in river catchments might pose a hazard for the safety of infrastructures, such as dams and river dwellers, and thus is often removed. Génissiat dam in France presents a case study where annually approximately 1300 tons of driftwood are removed to prevent driftwood sinking and to protect the dam infrastructure. Collected river driftwood is rarely studied for utilization purposes and is commonly combusted or landfilled. However, driftwood can be valorized for biochar production through pyrolysis or hydrothermal carbonization (HTC). This study follows a novel approach in characterizing river driftwood by identifying the different common genera present at Génissiat dam on the upper Rhône, France. Moreover, the research provides for the first time a comprehensive analysis of river driftwood different physico-chemical properties, such as moisture content, major elemental composition (CHNSO), HHV, and macromolecular composition (cellulose, hemicellulose, lignin, and extractives). The study shows that the transportation of driftwood through rivers can enhance its properties by reducing the bark content resulting in lower ash content. Results indicate that driftwood can be mixed and further processed as a feedstock regardless of their genera and type for biochar production by pyrolysis or hydrothermal carbonization.

Green Synthesis of Metal-Organic Framework Bacterial Cellulose Nanocomposites for Separation Applications.

Metal organic frameworks (MOFs) are porous crystalline materials that can be designed to act as selective adsorbents. Due to their high porosity they can possess very high adsorption capacities. However, overcoming the brittleness of these crystalline materials is a challenge for many industrial applications. In order to make use of MOFs for large-scale liquid phase separation processes they can be immobilized on solid supports. For this purpose, nanocellulose can be considered as a promising supporting material due to its high flexibility and biocompatibility. In this study a novel flexible nanocellulose MOF composite material was synthesised in aqueous media by a novel and straightforward in situ one-pot green method. The material consisted of MOF particles of the type MIL-100(Fe) (from Material Institute de Lavoisier, containing Fe(III) 1,3,5-benzenetricarboxylate) immobilized onto bacterial cellulose (BC) nanofibers. The novel nanocomposite material was applied to efficiently separate arsenic and Rhodamine B from aqueous solution, achieving adsorption capacities of 4.81, and 2.77 mg g‒1, respectively. The adsorption process could be well modelled by the nonlinear pseudo-second-order fitting.