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Abstract In this study, we introduce a novel application of wood as the construction material for Microbial Fuel Cell (MFC) containers, developing what we term the Wooden Membrane-less Microbial Fuel Cell (WML-MFC). This innovative approach leverages the natural properties of wood to enhance the sustainability and cost-effectiveness of MFCs. Employing three different types of wood—pine, oak, and black locust—the WML-MFC design incorporates a carbon felt anode inside the wooden container and a carbon cloth cathode wrapped externally. This configuration not only protects the cathode from biofouling but also utilizes the inherent moisture management capabilities of wood to maintain operational stability. The performance of these wooden MFCs was assessed in terms of electricity generation and water treatment efficacy. Pine and oak containers achieved maximum power densities (MPD) of 35 mW/m^2 and 4 mW/m^2, respectively, with corresponding maximum open-circuit voltages of 551 mV and 269 mV. Black locust showed the least effective bioelectricity generation. COD removal efficiency was observed between 18 and 48% for pine and 3% to 39% for oak over hydraulic retention times of 24–48 h. Notable water loss due to moisture diffusion was recorded at 20%/day in pine and 6%/day in oak. Durability assessments through DMA and SEM analyses confirmed the suitability of wood as a container material, emphasizing the dual environmental and economic benefits of this WML-MFC design.

ABSTRACTOne of the key elements of sustainability of humankind is the usage ratio of nature-based materials as opposed to synthetic products. This is very significant in the field of packaging materials, as people use and consume increasing amount of packaging materials every day. Packaging materials are usually produced from petroleum-based sources using non-degradable materials however, this has a negative impact on sustainability and the environment. It is important to replace them with natural-based materials, therefore cellulose is receiving more and more attention as a raw. Much research has been done for developing new nature-based packaging materials and technologies for replacement of synthetic materials. Recent articles review much research for developing methodologies, materials and composite materials for reducing environmental pollution. This paper reviews how natural-based packaging materials have spread and how it is used in many areas thanks to their favorable environmental effects. It summarizes the raw materials, additives and coatings of natural-based packaging materials, and it also addresses end-of-life options. The paper concerns also the most sensitive area of packaging is food packaging. Smart packaging is relevant for food packaging, and it seems to be one of the promising research areas for substituting artificial materials and providing additional functions.

Abstract In this work, a new type of structural sandwich panels made with laminated oil palm wood core and rubberwood-based oriented strand board (OSB)/plywood faces were introduced for energy-efficient wall applications in Thailand. Effect of the manufacturing process and material parameters including adhesive content (250 g/m2 and 500 g/m2), core configuration (cross or parallel laminated oil palm lumber) and density (low and medium) and face material type (rubberwood-based OSB/plywood) on panel’s properties were explored. The panels were produced using two-component polyurethane adhesive and a constant clamping pressure of 0.6 MPa. Adhesive content of 250 g/m2 was found to be sufficient for gluing all layers, with wood failure percentage of more than 80% as required by the standard. In-plane dimensional stability of the panels was mainly affected by the core configuration; it was better for cross laminated oil palm wood core sandwich panel. Higher core density resulted in increased density, thermal conductivity and compressive strength in the major direction but lower thermal resistance of the panel. The plywood face sandwich panels provided slightly higher compressive strength than OSB face sandwich panel, and their failure mechanisms were also different. The heat loss of these panels was about one-third of concrete and brick walls, hence, they can provide better insulation for indoor space. Based on the measured thermal conductivity, it was expected that these panels would pass the energy criteria according to Building Energy Code of Thailand. Thus, from the energy saving and sustainability perspectives, these panels can potentially be used as energy efficient wall panels for buildings, not only for Thailand but also for other tropical countries, where the oil palm wood and rubberwood resource is available.

The purpose of this paper is to experimentally study the thermal resistance (RSI value) of building insulation materials made mainly from natural fiber. Natural fibrous materials or renewable resources and their reinforcement composites are currently being used in building and construction as a potential solution to significantly reduce thermal load and energy consumption. The RSI value is used in describing the thermal efficiency of insulating material and in an analysis of heat transfer through the structural components of a building (such as walls, roofs, and windows) under steady-state conditions. In this study, the thermal resistance values of several samples made from coir fiber, rice straw fiber, energy reed fiber, and coconut wood were calculated from the thermal conductivity which was measured at mean temperature of 20°C, using the heat flow apparatus. The lowest RSI value was recorded in the phenol-formaldehyde polymer composites reinforced by rice straw fiber (0.115 m2·K·W-1) and coir fiber (0.128 m2·K·W-1) due to the relative thinness of the tested samples (8 and 12 mm). However, these samples can be used as an additional layer in multi-layered assemblies because of their low thermal conductivity value. The highest RSI value was reported on the binderless coir fiber panel (0.909 m2·K·W-1) at the thickness of 50 mm. Another investigation examined the relationship between RSI value and mean temperature to observe the influence of variations of ambient temperature on the heat resistivity of building insulation materials. Practical data showed the decreased linear proportion between thermal resistance and specific mean temperatures increased from 0 to 40°C. It is apparent that an increase in the interior and exterior temperature of a building significantly influences the thermal resistance of its insulation materials. Based on the experimental study, once the thermal conductivity coefficient of each sample was determined, the calculated RSI value was a valuable parameter to evaluate the thermal resistant effectiveness of a multi-layered installation, which allows us to investigate practically the effect of the thickness of additional layers from different insulating materials used in building envelopes.

One way of satisfying increased market demand and simultaneously achieving a reduced environmental load in the industrial paper production is the use of fibrous agricultural residues. The aims of this study were i) to investigate the effect of alkaline – hydrodynamic cavitation (HC) pre-treatments on the delignification of Miscanthus × giganteus stalks (MGS) and ii) establishing the suitability of MGS as feedstock and their exploitation in pulp and paper manufacturing. It was demonstrated that the proposed treatment is an efficient delignification method for the non-wood fiber sources, such as miscanthus. A significant outcome of this work was the observation that HC treatment preserved the fibres lengths and surface quality of raw MGS, but at the same time increased the amount of kinked and curled fibers present in cavitated miscanthus fibers. The average miscanthus fiber length was found to be relatively short at 0.45 (±0.28) mm, while the slenderness ratio, the flexibility coefficient and Runkel ratio values were calculated to be 28.13, 38.16 and 1.62, respectively. The estimated physical properties of MGS pulp hand-sheets were 24.88 (±3.09) N m g−1 as the tensile index, 0.92 (±0.06) kPa m2 g−1 as the burst index and 4.0 (±0.37) mN m2 g−1 as the tear index. Overall the current work demonstrated effective use of hydrodynamic cavitation for improving the processing in pulp and paper manufacturing.

Formaldehyde in the indoor air is one of the chemicals causes health risk, that’s why it is strived to reduce formaldehyde emissions from different wood products. There are many chemical compounds in the bark, including tannins, which can react with formaldehyde. The aim of this study was to reduce the formaldehyde emission from HDF with mixing poplar bark powder into the raw material. 2, 4, 6 and 8% (based on dry weight). Populus ×euramericana cv. Pannónia bark was mixed to the fibers, and HDF panels were manufactured with urea-formaldehyde resin. Mechanical properties; color change and formaldehyde release were measured. Contrary to expectations the mixed bark didn’t reduced the formaldehyde emissions, but the mechanical properties deteriorated by the bark powder.

Two oak cant timbers were sawn up to a total of 58 boards. As a dependent variable, the energy consumption while manufacturing a board was measured. As influencing variables, timber and saw blade characteristics were assessed, including density, moisture content, log feed speed, blade profile, and sawing sequence. Four types of forces acting in a saw-tooth were derived, namely, the dust particle shaving force, the particle accelerating force, the dust compressing force, and the frictional force as a consequence of blade wear. The experiment showed that the most prominent factor is the shaving force if the blade was newly sharpened, and that the dust accelerating and compressing forces were negligibly small. The frictional force grew from insignificant at the first board to more than one fourth of the force total at the 58th board. With each board, the saw tooth tips receded by more than 2 μm. With these data, the course of blades’ deterioration from wear was characterised.

An experimental study of wood impregnation was implemented by applying centrifugal methods. The impregnants were a 10% aqueous solution of potassium chloride and a 2% aqueous solution of borax. Birch (Betula pendula) and aspen (Populus tremula) wood samples in different moisture content were tested. The impregnation time in the centrifugal device were 30 seconds repeated 21 times, and the samples were measured after every 30 seconds. The experimental results were fitted to a nonlinear filtration law, which indicated that the centrifugal wood impregnation was dependent on wood species, wood moisture, rotational speed, and radius. Determination of rotational speed and centrifuge radius for impregnating aspen and birch at varying lengths and humidity under conditions of the nonlinear impregnant filtration law can be done using the example charts that were developed and presented in this study.

Dry thermal treatments of wood samples were carried out at 160 and 200 °C. After each treatment, the samples were irradiated using a strong UV emitter mercury lamp, and the colour change was then evaluated. For control, untreated samples were also irradiated using the same mercury lamp. Results showed that the extractive content of the wood played an important role in the colour change not only during thermal treatment but also during light irradiation. It was found that, compared to the thermally untreated samples, the thermal treatment at 200 °C reduced the red colour change due to photodegradation. The yellow colour change of photodegradation was hardly affected by the applied thermal treatments, showing that thermal treatments were not able to reduce the light degradation of lignin. The applied treatments slightly stabilized the wood against the degrading effect of light. The wood treated at lower temperature (160 °C) had less colour change induced by the light source.