Non-fossil Resources Research Articles

CO2 utilization: Developments in conversion processes

Abstract Carbon dioxide capture, utilization and storage (CCUS) –including conversion to valuable chemicals-is a challenging contemporary issue having multi-facets. The prospect to utilize carbon dioxide (CO2) as a feedstock for synthetic applications in chemical and fuel industries -through carboxylation and reduction reactions-is the subject of this review. Current statute of the heterogeneously catalyzed hydrogenation, as well as the photocatalytic and electrocatalytic activations of conversion of CO2 to value-added chemicals is overviewed. Envisaging CO2 as a viable alternative to natural gas and oil as carbon resource for the chemical supply chain, three stages of development; namely, (i) existing mature technologies (such as urea production), (ii) emerging technologies (such as formic acid or other single carbon (C1) chemicals manufacture) and (iii) innovative explorations (such as electrocatalytic ethylene production) have been identified and highlighted. A unique aspect of this review is the exploitations of reactions of CO2 –which stems from existing petrochemical plants-with the commodity petrochemicals (such as, methanol, ethylene and ethylene oxide) produced at the same or nearby complex in order to obtain value-added products while contributing also to CO2 fixation simultaneously. Exemplifying worldwide ethylene oxide facilities, it is recognized that they produce about 3 million tons of CO2 annually. Such a CO2 resource, which is already separated in pure form as a requirement of the process, should best be converted to a value-added chemical there avoiding current practice of discharging to the atmosphere. The potential utilization of CO2, captured at power plants, should also been taken into consideration for sustainability. This CO2 source, which is potentially a raw material for the chemical industry, will be available at sufficient quality and at gigantic quantity upon realization of on-going tangible capture projects. Products resulting from carboxylation reactions are obvious conversions. In addition, provided that enough supply of energy from non-fossil resources, such as solar [1], is ensured, CO2 reduction reactions can produce several valuable commodity chemicals including multi-carbon compounds, such as ethylene and acrylic acid, in addition to C1 chemicals and polymers. Presently, there are only few developing technologies which can find industrial applications. Therefore, there is a need for concerted research in order to assess the viability of these promising exploratory technologies rationally.

Low Density Sugarcane Bagasse Particleboard Bonded with Citric Acid and Sucrose: Effect of board density and additive content

The development of natural adhesives derived from non-fossil resources is very important for the future. In this study, by taking sugarcane bagasse as the raw material, without using any synthetic resin but adding some eco-friendly additives (citric acid and sucrose), low density particleboards were successfully developed. The effects of board density and additive contents on the physical and mechanical properties of the boards were investigated. The bonding mechanism was observed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The results showed that the low density bagasse particleboard had good mechanical properties and dimensional stability relative to its low board density. The modulus of rupture (MOR) and the thickness swelling (TS) values increased with increasing board density. The board with a density of higher than 0.40 g/cm³ and manufactured at 15% additive content can meet the requirements of the Chinese national forestry industry standard LY/T 1718-2007 (2007). Based on the results of the FTIR spectra, the additive not only increased the hydrogen bond but also the molecular linkage force (C-O-C). X-ray diffraction showed the relationship between crystallinity of cellulose and the strength of particleboard.

Investigation of a new natural adhesive composed of citric acid and sucrose for particleboard

The development of a natural adhesive composed of materials derived from non-fossil resources is a very important issue. In this study, only citric acid and sucrose were used as adhesive materials for particleboard. A water solution in which citric acid and sucrose were dissolved was used as an adhesive, and the manufacture of particleboard with a target density of 0.8 g/cm3 was attempted under a press condition of 200 °C for 10 min. The optimum mixture ratio of citric acid and sucrose and the optimum resin content was 25–75 and 30 wt%, respectively. The modulus of rupture (MOR) and the modulus of elasticity in bending were 20.6 MPa and 4.6 GPa, respectively. The internal bond strength (IB) was 1.6 MPa, indicating that the adhesive had excellent bond strength. The thickness swelling (TS) after water immersion for 24 h at 20 °C was 11.9 %. The board did not decompose even under more severe accelerated treatments. This meant that the adhesion had good water resistance. The MOR, IB and TS of the board were comparable to or higher than the requirement of the 18 type of JIS A 5908 (2003). Consequently, there is a possibility that a mixture of citric acid and sucrose can be used as a natural adhesive for particleboard.

Cover Picture: Chemical Technologies for Exploiting and Recycling Carbon Dioxide into the Value Chain (ChemSusChem 9/2011)

Carbon dioxide, a renewable resource: The cover illustrates the vision of utilizing the greenhouse gas CO2 as feedstock for chemical production. With the implementation of carbon capture technologies, CO2 will become available in vast quantities as an economically attractive resource. On condition that an adequate supply of energy from non-fossil resources for chemical processing is ensured, the use of this CO2 would harvest nature's carbon resources most directly, without the by-pass via biomass or fossil resources and could open up a complementary strategy contributing to a closed anthropogenic carbon cycle. In a Review on page 1216, Leitner and Müller et al. discuss strategies to identify the most interesting products and chemical pathways for the utilization of CO2. The cover image was prepared by Thorsten Groetker (FairyDustInc).

Evaluating meteorological climate model inputs to improve coastal hydrodynamic studies

Abstract. This work compares meteorological results from different regional climate model (RCM) implementations in the Mediterranean area, with a focus on the northern Adriatic Sea. The need to use these datasets as atmospheric forcings (wind and atmospheric pressure fields) for coastal hydrodynamic models to assess future changes in the coastal hydrodynamics, is the basis of the presented analysis. It would allow the assessment of uncertainties due to atmospheric forcings in providing coastal current, surge and wave climate changes from future implementations of hydrodynamic models. Two regional climate models, with different spatial resolutions, downscaled from two different global climate models (whose atmospheric components are, respectively, ECHAM4 and ECHAM5), were considered. In particular, the RCM delivered wind and atmospheric pressure fields were compared with measurements at four stations along the Italian Adriatic coast. The analyses were conducted using a past control period, 1960–1990, and the A1B IPCC future scenario (2070–2100). The chosen scenario corresponds to a world of very rapid economic and demographic growth that peaks in mid-century, with a rapid introduction of new efficient technologies, which balance fossil and non-fossil resources (IPCC, 2007). Consideration is given to the accuracy of each model at reproducing the basic statistics and the trends. The role of models' spatial resolution in reproducing global and local scale meteorological processes is also discussed. The Adriatic Sea climate is affected by the orography that produces a strengthening of north-eastern katabatic winds like bora. Therefore, spatial model resolution, both for orography and for a better resolution of coastline (Cavaleri et al., 2010), is one of the important factors in providing more realistic wind forcings for future hydrodynamic models implementations. However, also the characteristics in RCM setup and parameterization can explain differences between the datasets. The analysis from an ensemble of model implementation would provide more robust indications on climatic wind and atmospheric pressure variations. The scenario-control comparison shows a general increase in the mean atmospheric pressure values while a decrease in mean wind speed and in extreme wind events is seen, particularly for the datasets with higher spatial resolution.

Application of citric acid as natural adhesive for wood

AbstractThe development of natural adhesives derived from nonfossil resources is very important for the future. Besides, it is desirable to be safe adhesives without using harmful chemical substances. In this study, application of citric acid as a natural adhesive was investigated. Citric acid powder and bark powder obtained from Acacia mangium were used as raw materials. Citric acid powder was mixed with the bark powder, and the resulting powder mixture was poured into a metal mold. The mold was hot‐pressed at 180°C and 4 MPa for 10 min, and a bark molding was then obtained. The specific modulus of rupture and modulus of elasticity values of the molding containing 20 wt % citric acid were 18.1 MPa and 4.9 GPa, respectively. The molding did not decompose during a repeated boiling treatment. To clarify the effect of tannin on the adhesiveness of molding, bark was separated into tannin and residue. The molding was not obtained while using the tannin due to the marked fluidity, whereas it was obtained while using the residue, the same as while using the bark. It was considered that components other than tannin contributed to the adhesiveness. Based on the results of Fourier transform infrared spectra, the formation of ester linkages between carboxyl groups derived from citric acid and hydroxyl groups in the bark was confirmed. Accordingly, citric acid brought an adhesion by chemical bonding, and it could be used as a safe natural adhesive. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

A Global Assessment of Hydrogen for Future Automotive Transportation: Projected Energy Requirements and CO2 Emissions

ABSTRACT The proposed transition to hydrogen is aimed at resolving global issues, such as petroleum scarcity and CO2 emissions, so it is sensible to look at this transition at a global level. In this paper, we present a model, named the World Hydrogen Transition Model (WHTM), that seeks to achieve two goals: 1) a projection of requirements for worldwide automobile travel measured in vehicle-kilometers traveled through the end of the 21st century, and 2) a prediction of hydrogen and underlying energy resource requirements based on different scenarios for improvement in vehicle efficiency, introduction of fuel cell vehicles, and introduction of hydrogen produced from non-fossil resources. The model includes industrializing and less developed as well as industrialized countries. Results from the model suggest that, for a range of likely scenarios, energy consumption for automobile travel will be as great or greater than current levels. However, if the transition to hydrogen fuel cell vehicles can be carried out successfully in the middle of the century, and is then followed by a transition to hydrogen from non-fossil resources, total petroleum consumption and CO2 emissions from the automobile sector could be greatly reduced compared to current levels, thereby making motorized personal transportation more sustainable. Applicability to other emerging zero-carbon vehicle options, such as plug-in hybrid electric vehicles (PHEVs), is also discussed.

Nuclear electricity for sustainable development: Egypt a case study

Egypt is a fast growing country with 78.9 million population and annual per capita installed power 0.286 MW as of July 2008. Moderate to mature population and economic growth trends forecast population and annual per capita installed power to reach 111 millions and 0.63 MW, respectively by 2032; and 128 millions at per capita power of 1.02 MW by 2052. With these trends in consideration installed electricity generation capacity are forecasted at 70 GW by 2032 and 132 GW by 2052 as compared to the 2008 installed power of 22.6 GW. Meeting these demands is almost impossible using known limited national fossil fuel reserves. Current electricity generation policy exhausts about 65% of country’s total fossil production. Crude oil reserves are expected to deplete by 2012, while gas reserves will be overstrained starting from 2030. A major policy shift towards the use of non-fossil resources is to be adopted. In the article Egypt’s major primary energy resources are evaluated. Electricity generation plans till 2022 are presented and an electricity generation strategy based on gradual introduction of nuclear power starting from 2018 is outlined. A balanced generation mix based on 72.7% fossil, 13% nuclear and 14.3% renewables is targeted by 2052. The mix is supposed to meet Egypt’s electricity needs by 2052 and to improve country’s energy sustainability.

Maximum fossil fuel feedstock replacement potential of petrochemicals via biorefineries

The search for feedstock replacement options within the petrochemical industry should logically be based upon non-fossil resources. Retaining the functionality of the biochemicals in biomass for use as chemical products and precursors can lead to a sizeable reduction of fossil fuel consumption. This was assessed by using a limited energetic and exergetic cradle-to-factory gate analysis following the principles of life cycle assessments (LCA). A calculation matrix was created for 16 bioenergy crops in their corresponding regions and for a conceptual biorefinery oriented towards existing bulk-chemical products. The optimal biorefinery cropping system was determined according to the fossil fuel mitigation efficiency in relation to chemical feedstock products and land use consumption. The “worst” performer still has a replacement potential of 22.2 GJ energy/ton product and 125 GJ energy/ha while the “best” performer can achieve 50.8 GJ energy/ton product and 721 GJ energy/ha. In addition to energy, exergy evaluation was included, to indicate potential areas of energy efficiency improvement. The combined evaluations demonstrate that the highest potential of biomass to replace fossil fuel resources is as an alterative feedstock source in the petrochemical industry.

Recent energy investigations on fossil and alternative nonfossil resources in Turkey

Recently, considerable attention has been focused on energy resources and energy investigations in Turkey. Domestic energy consumption accounts for 37% of the total energy consumption. The Turkish Government’s investment needs in the energy sector for the period 2000–2010 will be around US $55 billion. Of this, about 81% is total planning investments. A major dilemma now faced by Turkey is how to invest in new electric power capacity while, at the same time, adhering to foreign debt ceilings under lending rules set by the IMF. Turkey has to adopt new long term energy strategies to reduce the share of fossil fuels in the primary energy consumption. In recent times, the development of alternative energy sources has been a major focus of the research effort in Turkey.

Energy and the Environment: Alternatives in UK for CO2 Reduction

This paper examines energy alternatives in the UK and worldwide to reduce CO2, SO2, and NOx emissions up to the year 2020: environmental mechanisms in restructured markets, future energy alternatives, green electricity, energy efficiency, and pricing. At the outset, world energy resources, nonfossil resources, world energy demand, and the role of existing and planned mechanisms to achieve environmental benefits in restructured electricity markets are reviewed. Technological and institutional challenges of real, long-term reductions in carbon dioxide and other emissions from the electric sector are discussed. The paper then focuses on renewable energy in the UK, the green pool, and trends in power marketing considering green pricing programs, and public policy for renewable energy. Considered is trends in energy supply structure: energy consumption and CO2 release, role of nuclear power, and European efforts for controlling CO2 emissions. The main part of the paper presents a case study on ensuring future energy alternatives for the UK based on simulations. Tables are presented illustrating basic technological aspects of a number of alternative energy mix strategies devised to meet the UK's electric service requirements where CO2, SO2, and NOx emissions are addressed. They combine the introduction of new natural gas-fired combined-cycle generation with alternate levels of demand side management-predominantly technology driven conservation, and for some of the strategies, wind power, tidal power, and hydro power from Iceland is included. Each class of technologies is phased in during the 20-year study period of 1999-2020. Comparative values for CO2, SO2, and NOxemissions are given.

Hydrogen: an accommodating fuel

A controlling influence on hydrogen as an energy vector will be the competitive position of electricity. Development of the distribution infrastructure for hydrogen can be expected to complement the electric system, the two together providing an optimum energy network. Hydrogen will be an accommodating fuel: fossil hydrogen helping, in some markets, to extend the use of fossil fuels as primary energy sources; nonfossil hydrogen later providing an alternative to electricity as an energy carrier for some developing nonfossil resources.