Carbonate, neutralization

Figure 2 illustrates a proposed growth process[3] of a polyhedral nanoparticle, along with a nanotube. First, carbon neutrals (C and C2) and ions (C )[16] deposit, and then coagulate with each other to form small clusters on the surface of the cathode. Through an accretion of carbon atoms and coalescence between clusters, clusters grow up to particles with the size fi-... 

The use of the lignin fraction is much more cumbersome currently the best-known chemical of a real commercial importance is vanillin, which is obtained by oxidation of the black liquor. Another example is a product called spray-dried lignosulfonate (as sodium salt) obtained from the older, acidic sulfite pulping process. It is sold as a commercial product primarily as a concrete additive for enhanced strength. Since the cement industry is one of the big contributors of carbon dioxide emissions (due to the production of calcium oxide from calcium carbonate), the use of this renewable, wood-derived product not only is fossil-carbon neutral in itself but also reduces carbon dioxide emission due to the diminished need for cement in large infrastructures made of concrete. 

Biofuels Carbon neutral Higher biodiversity Local source of energy Mitigate climate change Renewable fuels Ceotto (2009) Lai (2009d, e) Hill (2009) Miah and Hussein (2009) Scholz et aL (2009)... 

Fig. 15.1 The world energy supply in the two Shell long-term energy scenarios Dynamics as Usual and Spirit of the Coming Age. The stacking order is such that carbon-neutral electricity-delivering sources (hydro, nuclear and renewables excluding biofuels) are at the bottom. When overlaid with the energy demand of the electricity sector (lower hashed area) one observes that carbon-free electricity supply falls far short of electricity...

To meet the demand for 10-20 TW of carbon neutral energy, three options are viable (a) fossil fuel use in conjunction with carbon sequestration (b) nuclear power (c) renewable sources. 

The material that is harvested can be utilized in products, and when they are disposed of, the sequestered carbon is returned to the atmosphere. This gives rise to the often-quoted property of timber as being carbon neutral . However, this is erroneous, in that harvesting, transport and conversion of timber all result in net carbon emissions, which must be taken into account in carbon balances. But if the timber is used to substitute for products that have higher carbon emissions, then real gains are achieved. The arguments for the utilization of timber are complex and outside the scope of this book, but the following conclusions can be drawn ... 

Puri and collaborators (3d, 59) found that the amount of CO2 given off on heating to 1200° was always equivalent to the Ba(OH)2 or NaOH neutralization. Evolution of COj was complete between 750 and 900°. Samples oxidized in liquid medium evolved more COg in relation to CO on heating than did samples treated with oxygen (3d, 55). Puri and Bansal (59) suggested that the neutralization of alkali was caused by carbon dioxide chemisorbed on the carbon surface ( COg complex ). If carboxyl groups were responsible, 1 mole of COg should be formed for each equivalent of alkali consumed. The author of this article thinks, as will be shown below, that very likely carboxyl groups of different environment are responsible for bicarbonate and carbonate neutralization as well as COg evolution. 

Rivin 83,84) found a close agreement between NaHCOj neutralization by carbon blacks and their adsorption capacity for diphenylguanidine from benzene solution. The carbonate neutralization, again, was twice the bicarbonate value 84). The carbon dioxide evolved on vacuum pyrolysis was roughly equivalent to the carboxyl content. 

Hydrogen can be produced from carbon-free or carbon-neutral energy sources or from fossil fuels with CO capture and storage (sequestration). Thus, the use of hydrogen could eventually eliminate greenhouse gas emissions from the energy sector. 

Evaluation of life cycle analysis (LCA) is thought to be important to confirm whether a process is really environmentally friendly or not. When the carbon source of some products comes from renewable resources, it is called carbon neutral and it is often thought that this means that a product is good for environment. But, as shown in Fig. 20, a lot of CO2 must be generated in every process and we have to accumulate all of that generated CO2 to evaluate the efficiency of the production process. ... 

A schematic illustration of the model is shown in Figure 10.2.12, together with that of polyhedral nanoparticles which grow as byproducts of MWNTs (see Fig. 10.2.3). An initial seed of an MWNT is the same as that of a polyhedral nanoparticle. Carbon neutrals [C, C2 (19)] and ions (C+) deposit and coagulate with each other to form atomic clusters and fine particles on a surface of the cathode. Structures of the particles at this stage may be amorphous with high fluidity (liquidlike) because of the high temperature ( 3500 K) of the electrode surface and ion bombardment. 

Incinerator stack emission air from contaminated building (CDDs) Addition of 13C-labeled TCDD to collection tube followed by collection of sample addition of internal standards Soxhlet extraction clean-up and sequential fractionation on acidic silica/potassium, silicate/silica gel, acidic alumina, carbon, neutral alumina columns volume HRGC/HRMS (MIM) 1 pg/m3 No data Smith et al. 1986b... 

The concept of this process is shown in Figure 6. The carbon in biomass which is fixed by photosynthesis from atmospheric C02 is converted into i) solid carbon (various kinds of charcoal, carbon and graphite) for use as materials or for storage, which is a stable state of carbon element ii) synthetic fuels such as FT diesel oil, DME or hydrogen, which can replace fossil fuels as carbon neutral alternate fuels (Hori, 2007, 2007a, 2007b). 

A new energy system in which carbon is reused cyclically was discussed. A carbon recycle system has already existed in nature as a natural carbon neutral system. In this paper, a concept of an Active Carbon Neutral Energy System (ACRES) was proposed against the natural system. C02 is regenerated artificially into hydrocarbons consuming a primary energy source with no C02 emission, and re-used cyclically in ACRES. ACRES recycles carbon, and transform energy without C02 emission. Because ACRES was expected to solve the above carbon problems, the feasibility of ACRES was discussed thermodynamically. 

Current medium-scale operations for HTC calculate operating expenses on the order of 200/ton biocoal, not including a forthcoming economy of scale and further technical optimization. Even at this premature level, this corresponds to 2.7 (euro) cents/kWh heat (i.e. it can nicely compete with current energy media, being carbon neutral at the same time). 

Whether this carbon is used as a carbon-neutral energy carrier or indeed to compensate for other C02 sources is not a simple question, depends on natural resources and national development, and is in the end also a question of societal values and political agreements. If the energy content is valued on the market more than the bound C02 and the boxed climate change, it is safe to predict that we will experience a renaissance of carbon-based machines. 

Centi G, Perathoner S, Passalacqua R, Ampelli C. Solar production of fuels from water and C02. In Muradov NZ, Veziroglu TN, editors. Carbon-neutral fuels and energy carriers. Boca Raton, FL CRC Press (Taylor Francis Group) 2012. p. 291-323. 

Methanol is particularly interesting because it can be produced by hydrogenation of the greenhouse gas C02 (see Section 5.3.5). Thus, anthropogenic C02 (e.g. from industrial exhaust or coal power plants) could be used for its manufacture. The amount of C02 emitted upon methanol combustion is then equal to the amount consumed during its production. Such C02 recycling via methanol has been proposed by Olah et al. [2] as a carbon-neutral methanol economy. ... 

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