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Manufacturing processes and their economy are dramatically evolving due to machinery and digital control improvements. Artificial intelligence, big data analytics, and the Internet of Things are key tools for this new industrial revolution era based on Industry 4.0. Bioeconomy and circular economy concepts have appeared in the forest, agriculture, food, pharmaceutical, pulp and paper, chemical, biotechnological, and energy areas, etc., to achieve sustainable economic growth development via biomass valorization in a biorefinery platform. Biorefinery process development at an industrial scale requires the previous design and assessment of processes and technologies. Therefore, economic, environmental, and social factors should be evaluated to prevent the failure in one of these issues that could affect the performance of the others. With a growing interest in sustainable economic development, there is a need to incorporate new technologies early enough in the process design. This study aims to better understand how Industry 4.0 era tools can bring new solutions to the biorefinery process design, in terms of the technical, economic, environmental, and social factors. Thus, these tools could improve and revolutionize the process selection optimization, provide alternatives for biomass valorization, integration strategies, and the metrics selection for process evaluation, adding the approach toward sustainable economic development.

Gamma-valerolactone (GVL) is a highly reactive keto-lactone and a promising platform biomolecule, used as an additive for food and fuels, green solvent, and fuels precursor, among others. Its production from biomass usually involves hydrogenation and subsequent cyclization of levulinic acid or its esters. The process of conventional hydrogenation requires high pressures and temperatures, an external hydrogen source, and scarce noble/precious materials as catalysts. However, it could be produced under mild conditions, using bifunctional metal-acid catalysts with high metal dispersion and meso or microporosity, high surface area, temperatures lower than 200 °C, pressures ≤ 1MPa, and secondary alcohols (such as isopropanol) as hydrogen donors. The catalytic transfer hydrogenation followed by cyclization (CTHC) of levulinic acid (LA) and its esters (LE) to produce GVL using secondary alcohols as H donor is a great alternative. Variables involved in CTHC such as raw material, time, temperature, and type of catalyst, mainly transition metals and their combinations, are reviewed in this work.

Agroforestry wastes are industrial byproducts available locally such as eucalyptus sawdust (EUC) and sugarcane bagasse (SCB). These byproducts can be used as lignocellulosic raw materials to produce high-value products. This study is a techno–economic analysis of four potential scenarios to produce polyhydroxybutyrate (PHB) and levulinic acid (LA) from hemicellulosic sugars by a fermentative pathway in a biomass waste biorefinery. Mass and energy balances were developed, and technical and economic assessments were carried out to obtain gas, char, and tar from residual solids from autohydrolysis treatment. It was determined that microbial culture could be an attractive option for added-value product production. More than 1500 t/year of PHB and 2600 t/year of LA could be obtained by the proposed pathways. Microbial and enzymatic conversion of LA from sugars could significantly improve energy consumption on the conversion strategy. The products from solid residual valorization (char and tar) are the most important for economic performance. Finally, a variation in specific variables could mean substantial improvements in the final indicators of the processes, reaching a higher NPV than USD 17 million.

La disminución en las reservas de petróleo a nivel mundial y los problemas medioambientales ocasionados por su utilización, propician la búsqueda de nuevas alternativas renovables y menos contaminantes. En este trabajo se estudió el comportamiento de enzimas celulasas y celobiosas, junto con cepas de Saccharomyces cerevisiae, Candida kefyr, Candida tropicalis y Candida guilliermondii en el proceso de hidrólisis y fermentación simultánea (SSF) conducido a 35°C para la producción de bioetanol, a partir de los carbohidratos presentes en cascarilla de arroz. Este proceso busca hidrolizar la celulosa y aprovechar de inmediato los azúcares fermentables, atravesando la dificultad de la diferencia entre la temperatura óptima para el desempeño de enzimas (50°C) y la de levaduras (25°C a 35°C). La cascarilla fue pretratada con una secuencia ácido-alcalina para la separación de los carbohidratos. Los mayores % de bioetanol se obtuvieron con Saccharomyces cerevisiae (68%) y Candida kefyr (75%).

Soda-ethanol pulps, prepared from a forestry residue pine sawdust, were treated according to high-consistency enzymatic fibrillation technology to manufacture nanocellulose. The obtained nanocellulose was characterized and used as ink for three-dimensional (3D) printing of various structures. It was also tested for its moisture sorption capacity and cytotoxicity, as preliminary tests for evaluating its suitability for wound dressing and similar applications. During the high-consistency enzymatic treatment it was found that only the treatment of the O2-delignified pine pulp resulted in fibrillation into nano-scale. For 3D printing trials, the material needed to be fluidized further. By 3D printing, it was possible to fabricate various structures from the high-consistency enzymatic nanocellulose. However, the water sorption capacity of the structures was lower than previously seen with porous nanocellulose structures, indicating that further optimization of the material is needed. The material was found not to be cytotoxic, thus showing potential as material, e.g., for wound dressings and for printing tissue models.

The black carob tree (Prosopis nigra) is a particularly valued species in Chaco, Argentina on account of its hard wood. Finding a use for the sawdust, the main industrial residue of wood, could be useful within the furniture industry of any country in the tropics seeking to apply the biorefinery concept. For the conversion of wood carbohydrates to bioethanol, a pretreatment stage is necessary. The objective of this work was to find the acid pretreatment conditions that maximize the extraction of xylose with minimum degradation, while maximizing the concentration of glucans in the pretreated solid to obtain better enzymatic accessibility, using black carob tree sawdust as the raw material. The optimization was carried out by use of a central composite design (CCD) with two independent variables: the concentration of the sulfuric acid solution and the heating time. Optimal enzymatic hydrolysis occurred at the mean values of the tested acid solution concentration (1.2%) and after shorter heating times (10.2 min). The concentration of sugars after the enzymatic hydrolysis of the pretreated solid over a time period of 72 h was three times higher than the untreated solid.

El objetivo del trabajo fue determinar la edad de transición de madera juvenil a madura a partir de las propiedades de la madera en un clon de álamo. Se muestrearon cinco árboles de 17 años de Populus deltoides “Australia 129/60” de una plantación comercial. Se tomaron muestras a cinco alturas en el fuste: 0,3 m, 1,3 m, 4,2 m, 8,1 m y 15,9 m y se determinó anualmente: crecimiento, densidad de la madera, morfometría de fibras y vasos y área de pared. La edad de transición de madera juvenil a madura se determinó por el método de regresión segmentada. Los patrones de variación radial y axial de las diferentes propiedades fueron de un aumento de sus magnitudes con la edad y altura en el fuste. La edad de transición entre madera juvenil y madera madura no fue idéntica para todas las propiedades, definiéndose edades de transición de 4, 5, 7 y 9 años dependiendo de la variable. La secuencia de maduración fue: área de pared, diámetro y frecuencia de vasos, ancho y longitud de fibras, densidad y espesor de pared. Las propiedades de la madera juvenil fueron inferiores con respecto a la madura, >siendo el volumen del cilindro juvenil del 52%. Abstract The aim of this work was to determine the age at which the transition of the juvenile wood to the mature wood takes place, by means of the parameters: density, morphometry of fibers, and vessels in one poplar clone. Five 17-year-old Populus deltoides “Australia 129-60” trees were sampled from a commercial plantation in Buenos Aires, Argentina. Samples were taken at 5 heights from the trunk: 0.3 m, 1.3 m, 4.2 m, 8.1 m and 15.9 m and the annual radial growth, wood density, morphometry of fibers and vessels, and cell wall area were measured. Segmented regression analyses were used to determine the age of transition from juvenile to mature wood. The radial variation of different anatomical properties increased with age. The estimated age of transition from juvenile wood and mature wood was not identical for all properties. The transition ages were 4, 5, 7 and 9 years depending on the variable. The sequence of maturation was: cell wall area, vessel diameter and frequency, fiber width and length, density and wall thickness. Juvenile wood properties were significantly lower with respect to the mature wood. The volume of the juvenile wood was 52%.

El objetivo del trabajo fue analizar los patrones de variación axial y radial de la densidad y morfometría celular de la madera de sauce americano y determinar la edad de transición de madera juvenil a madura. Se muestrearon cinco árboles de 45 años de Salix babylonica de Entre Ríos, Argentina. Se tomaron muestras a tres alturas en el fuste y en 9 posiciones radiales y se determinó la densidad básica y la morfometría de fibras y vasos. Los patrones de variación radial evidenciaron un leve aumento de magnitud con la edad, mientras que la mayor variación axial se manifestó mayoritariamente entre la base y la altura de 1,3m el fuste, presentándose diferentes tendencias de acuerdo a la variable. Dependiendo de la variable analizada, la edad de transición entre madera juvenil y madura fue de 5 a 10 años o de 10 a 15 años. La longitud y ancho de fibras y el diámetro de vasos fueron los primeros parámetros en madurar. Los valores promedio de las variables de la madera juvenil y madura no mostraron diferencias importantes entre los leños, por lo tanto podrían considerarse como homogéneos desde el punto de vista anatómico y de densidad. Abstract The aim of this work was to determine the patterns of axial and radial variation of the density and cellular morphometry of american willow wood, for determining the age of transition from juvenile to mature wood. The study was conducted on five trees of a 45-years-old plantation of a clone of Salix babylonica, from Entre Rios, Argentina. Samples were taken at three heights and at 9 radial positions of the stem for the determination of basic density and morphometry of fibers and vessels. The radial variation patterns showed a slight increase in magnitude with age, whereas the axial variation showed up between the base and a height of 1.3 m in the stem, presenting different tendencies according to the variable. Depending on the analyzed variable, the age of transition between juvenile and mature wood was 5 to 10 years, or 10 to 15 years. Fiber length and width and vessel diameter were the first characters to mature. The average values of the properties of juvenile and mature wood showed no substantial differences between logs, therefore they could be considered as anatomically and density homogeneous.