PAPERmaking! g FROM THE PUBLISHERS OF PAPER TECHNOLOGY Volume 1, Number 1, 2015
Lignocellulosic Biomass and Its Usages The estimated worldwide production of renewable biomass for use in biofuels, fibres, and agriculture is currently 210.7 x 106 tons per year. An exact value is difficult to obtain because there is a large variation in production between countries. However, the importance of biomass to the modern economy is clear. Lignocellulosic biomass comprises wood and agricultural residues, which are sources of cellulose, hemicellulose, and lignin (the lignocellulosic fractions), and represents the major biomass source; since plants can contain high amounts of lignin (18% to 35% w/w), cellulose (40% to 50% w/w), and hemicellulose (10% to 35% w/w), lignocellulosic biomass are considered as one of the most promising sources of industrial raw material. Each of these types of lignocellulosic fractions has its own particular structural characteristics and chemistry, which can be exploited in chemical analyses. The biorefinery concept is an important strategy in the development of biomass usage and is based on the concept of a productive biomass chain similar to the petrochemical chain: fuels, energy, materials, bulk chemicals, and fine chemicals. Biorefineries use a large number of conversion processes (chemical, biochemical, and thermochemical) as a result of the chemical diversity of biomass and the high content of oxygen and water; analytical chemistry is required to understand and control these processes, their raw materials, products, and residues. The increase in the demand for bio-derived chemicals not only offers a great number of opportunities for green technologies and processes which use lignocellulosic biomass in biorefineries, based on the green chemistry principles, but it also presents several challenges related to market prices and replacement of non-renewable products (e.g., petrochemicals) for a renewable chemistry. Analytical Techniques and their Application For a general approach, the quality of the biomass used determines the product quality. Therefore, reliable information is required about the chemical composition of the biomass to establish the best use (e.g., most suitable conversion process and its conditions), which will influence harvest and preparation steps. Conversion processes should be monitored for their yield, integrity, safety, and environmental impact. Effluent or residues should be monitored and analysed for environmental control. Co-products need to be monitored to avoid interference with the product yield and product purity; however, co-products are also a good opportunity to add value to the biomass chain. Finally, products need to be monitored and analysed to determine their yields and purity and to ensure their quality. A recent review summarises the main techniques and their application for the analysis of biomass and its products (Vaz Jr. 2014). The most widely used analytical techniques for lignocellulosic biomass and products are briefly described below: x Gravimetry - determination of water content, by means of drying and weighing the material. Gravimetry can be applied for feedstock and product quality control; x Thermal analysis - determining the water content and ash, loss of mass for constituents versus temperature, thermal stability, among other parameters associated with temperature effects on the material: thermal gravimetric analysis
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Article 1 – Chemistry (biomass)
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