Abstract Nowadays, the dependence on fossil fuels is creating a particular instability in the global market. Moreover, waste management in urban areas is becoming a real problem. Different research groups all over the world are dealing with the resolution of both problems, using agricultural and urban wastes as an initial feedstock for the production of various fuels. In particular, using bioethanol turns out to be one of the most promising for two reasons: firstly, it is characterized by chemical–physical properties similar to gasoline (i.e., octane number, evaporation enthalpy, etc.); and secondly, it is easy to obtain fermentation processes from simple sugars. The problem of waste disposal strongly depends on lignocellulosic substrates, being lignin not easily fermentable like cellulose. Therefore, it became necessary to eliminate/separate it from the starting organic matrix. Pretreatments are used to separate the lignin and part of the hemicellulose from the starting matrix. This crucial point, for the transformation of lignocellulosic biomass into ethanol, is the most expensive process. For this reason, different types of pretreatments have been developed to find the most promising one, to be used in the industrial field, in terms of the total amount converted from an economic point of view. This chapter is an overview of the most widespread pretreatment types, highlighting advantages/disadvantages for each methodology.

One of the best-known greenhouse gases, CO2, has been increasing in the last decade of about 1.7%. To overcome the well-known global problems related to this gas, researchers of all over the world are working very hard in order to develop any strategies to seriously solve this issue. In this chapter, the authors focus their attention on one of the possible solutions to the problem: bacteria that are CO2 capture cells which have carried out this task since ancient times. In our work we make an excursus on all the biochemical processes of CO2 capture carried out by bacteria, ending with a detailed comparison of the most studied enzymes. One of the alternatives will be to genetically modify the organisms known to date to speed up their conversion process.

One of the most important problems in the worldwide community is the replacement of fossil fuels with renewable sources. In fact, in the last years, intense efforts from research groups around the world have been made in the development of the transformation from biomass to bioenergy in terms of yield and economic sustainability. In particular, one of the most promising renewable sources is considered lignocellulosic biomass for the following reasons: it has high productivity, requires low agricultural inputs, has positive environmental impacts, is easy to process, and does not compete with food crops. In particular, from this raw material is possible to obtain different types of biofuels such as syngas, biooil, and bioethanol. This chapter is focused on the production of bioethanol from renewable sources and aims to give an overview on the various steps of the production processes and the implementation of the technology by membrane reactors.

Nowadays, the world's energy requirements are based on the use of fossil fuels. Rapid growth in both global energy demand and carbon dioxide emissions associated with the use of these fuels have driven the research for alternative sources, which are renewable and have a lower environmental impact. Ethanol is considered one of them. In fact, it is considered one of the better biofuels for transport: it can be burned directly or blended with petrol to improve fuel combustion in vehicles, resulting in lower CO2 emission to reduce greenhouse gases in the atmosphere. The optimization of the ethanol production processes from lignocellulosic biomass is considered an important research from both industrial and research point of view. In function of the nature of the raw material, it is possible to distinguish these three different feedstock generations. In the first generation, the substrate consists mainly of seeds, potato, and grains and the production process consists of the purification of simple sugars to obtain ethanol. Nevertheless, the first generation of biofuels has been perceived as sustainable mainly from both an environmental and limitation in food supply point of view. This has meant that research has switched to the development of more advanced technology to obtain an energy sustainability to minimize greenhouse gases emission. For these reasons, other two different production processes have been developed, focusing on the fermentation of cellulose and hemicellulose from mainly agricultural wastes (second generation) and algae (third generation). This chapter represents a critical analysis of published data on application and potentiality of the bioethanol production from first, second and third generation of feedstock.

In the last century, a series of problems related to the environment, mainly due to polluting emissions such as CO2, CH4, and N2O, led to revaluation of a series of factors, including that of emissions from motor vehicles. To overcome the problem, new types of less polluting biofuels based on ethanol blends with fossil fuels, have been developed. United States, with the production of ethanol from corn, and Brazil, with the production of ethanol from sugarcane, currently drive the market for the world production of bioethanol, thanks mainly to government subsidies. Despite this, some problems related to energy loss during industrial processes and to the linkage of the first-generation feedstock with both biofuel and food for human consumption, are leading to the development of new-generation feedstocks which exploit lignocellulosic or algal biomasses. This chapter is a brief review of the methods of production of ethanol in the United States and Brazil, giving the generic economical and statistical data of the processes.

Methanol is currently considered one of the most useful chemical products and is a promising building block for obtaining more complex chemical compounds, such as acetic acid, methyl tertiary butyl ether, dimethyl ether, methylamine, etc. Methanol is the simplest alcohol, appearing as a colorless liquid and with a distinctive smell, and can be produced by converting CO2 and H2, with the further benefit of significantly reducing CO2 emissions in the atmosphere. Indeed, methanol synthesis currently represents the second largest source of hydrogen consumption after ammonia production. Furthermore, a wide range of literature is focused on methanol utilization as a convenient energy carrier for hydrogen production via steam and autothermal reforming, partial oxidation, methanol decomposition, or methanol–water electrolysis reactions. Last but not least, methanol supply for direct methanol fuel cells is a well-established technology for power production. The aim of this work is to propose an overview on the commonly used feedstocks (natural gas, CO2, or char/biomass) and methanol production processes (from BASF—Badische Anilin und Soda Fabrik, to ICI—Imperial Chemical Industries process), as well as on membrane reactor technology utilization for generating high grade hydrogen from the catalytic conversion of methanol, reviewing the most updated state of the art in this field.

Methanol, or methyl alcohol, is the simplest alcohol, appearing as a colorless liquid with a distinctive smell. Nowadays, it is considered one of the most useful chemical compounds. In fact, it is one of the most promising building blocks for obtaining more complex chemical structures, such as acetic acid, methyl tertiary butyl ether, dimethyl ether, methylamine, etc. Furthermore, methanol is also considered a promising clean-burning fuel with a high octane number. Knowing that CO2 and H2 are among the precursors in methanol synthesis, it is noteworthy that the conversion of CO2 to methanol can be considered a promising method for significantly reducing CO2 emissions, and that methanol production can also be used as a convenient energy carrier for hydrogen storage and conservation. In fact, methanol synthesis is the second source, after ammonia production, of hydrogen consumption (which has the highest energy content per weight) via several reactions, such as partial oxidation, steam reforming, autothermal reforming, methanol decomposition, or methanol-water solution electrolysis. Finally, among the recent attractive applications of methanol, the most promising for the future are the production of DME, the production of hydrogen, and the direct methanol fuel cell (DMFC). This chapter is an overview of not only common feedstocks used in the production processes for obtaining methanol (natural gases, CO2, or char/biomass), but also of the historical production processes (such as the BASF process, also known as the “high-pressure method,” and the ICI process, also known as the “low-pressure method”) and the most innovative trends for industrial applications.

New fiber composite materials are presented in this work. They have been obtained by treating the surface of the fibers with a silane reactant used in the compounding stage to connect vegetables and mineral fibers to the other chemical components of the final composite materials. The silane reactant links on the surface of the fiber forming strong covalent bonds through the Si atoms. The other end moiety of the silane reactant carries an ammine group which is able to bind to epoxides in a copolymerization process. In such a way the fiber themselves becomes part of polymer networks which have much better mechanical properties with respect to the composite materials obtained by simply dispersing the fibres into polymer matrices. The observed physical and mechanical proprieties of these fiber composites candidates them to have future interesting applications in the field of conservation of cultural heritage.

Selective relaxation rate measurements effectively proved the affinity of dexamethasone 21-phosphate disodium salt for quaternary ammonium-chitosan conjugates, their thiolated derivatives and the corresponding nanostructured aggregates. Affinity was also probed by dynamic dialysis. The release profile of dexamethasone loaded nanoparticles was defined by quantitative NMR and interrupted dialysis experiments, and mucoadhesivity of empty nanoparticles was effectively probed by selective relaxation rate measurements.

One of the most felt current problems in the worldwide scientific community is the replacement of fossil fuels with renewable sources. Fossil fuels as a source of energy have produced numerous unfavorable effects over the years, such as the decrease in air quality and the increase in global temperature. Nowadays, the rapid depletion of these fuels is provoking fluctuations in global market prices with relative crises in non-energy-independent states. Lignocellulosic biomass represents a largely widespread bio-derived carbon source on earth and a potential feedstock for obtaining ethanol, syngas, and fuels. Till now, their potential for reducing impacts and oil dependence has never fully exploited industrially. However, the increasing demand for renewable fuels and chemicals has pushed research toward new processing methods to recover and use this valuable biomass source. The purpose of this review, divided into four parts, is to review this research field, highlighting the most recent industrial developments for converting lignocellulosic biomass to biofuels. In this first part, after a brief discussion of the current energy production scenario, biomass sources will be classified. The production, structure, and composition of lignocellulosic biomasses will be discussed, focusing on biomass production costs, land use, and requirements for its conversion to biofuels.