REVIEW OF THE CURRENT INITIATIVES FOR CARBON DIOXIDE UTILIZATION TECHNOLOGIES IN EUROPE AND THE PROSPECTS FOR ROMANIA – PART I

Carbon Capture, Utilization, and Storage (CCUS) technologies comprise a set of proposed technological solutions (i.e. methods, measures, implementations, and policies) that seek to trap carbon dioxide – the main form of carbon carrier molecule responsible for the greenhouse effect, originating from human economic activities, and destabilizing the planetary climate – before its release into the atmosphere. The aim and function of CCUS manifest as either preventive measures that lock carbon dioxide permanently underground or in other suitable media (Carbon Capture and Storage, CCS), or as redirecting processes that feed it back to augmented industrial cycles for manufacturing products with positive financial impacts (Carbon Dioxide Utilization, CDU). Following recent initiatives at the European level and in view of the larger picture unfolding at the global theater, this digest review aims to deliver the main points, considerations, and dynamics that drive and formulate modern CCUS initiatives, focusing more on the recently surfaced CDU front. We will explore proposed pathways for materializing CDU by looking carefully on unfolding examples from such global and European arenas. We will then scrutinize plausible scenarios for transposing CDU to Romania to ask – and hopefully answer – the right questions as to how such scenarios can materialize.

Development of biocarbon sorbent from corn waste with increased destructive activity in relation to oil

The object of research is the created bioactive sorbent based on biochar from corn waste for the purification of oil-contaminated natural environments. The expediency of using biochar from corn cobs as a matrix – a carrier of microorganisms-destructors of petroleum hydrocarbons in the production of biosorbent – has been substantiated. Biochar meets the requirements for oil sorbents – environmental friendliness, oil resistance (6–8 g of oil per 1 g of sorbent), manufacturability and biocompatibility. The porous structure and chemical nature of the surface partly determines the absorbency of the material, but the dominant factor is the interaction of the hydrophobic surface with petroleum hydrocarbons. A universal oil oxidizer – a microbial complex isolated from oil-polluted natural objects, in combination with a carbon carrier, is capable of neutralizing oil pollution of various types and concentrations. It has been established that microorganisms – oil-destructors, immobilized on the surface of the sorbent, are capable of decomposing almost all oil hydrocarbons. Microorganisms immobilized on a carbon material have a great potential for destructive action. During immobilization, the viability of microbial cells is maintained, and the effect of their use is significantly increased. The use of a bioactive carbon sorbent based on biochar and immobilized natural oil-oxidizing microorganisms of a wide spectrum of action allows one to localize oil pollution and neutralize it through biodegradation. The optimal parameters for obtaining an oleophilic sorption matrix based on biochar from corn waste and for growing microbial biomass with a high destructive activity for oil hydrocarbons have been established. The optimum pyrolysis temperature is 300–350 °С, the pyrolysis time is 25–30 minutes. In this case, the sorption of oil obtained biochar reaches maximum values (6–8 g oil/gsorbent). Sufficient number of immobilized microorganisms – oil destructors 120–200·104 cells for active decomposition of oil localized on the sorbent surface. The operational characteristics of the obtained bioactive sorbents, technological features and methods of their use in cleaning the environment from oil pollution have been studied. The biosorbent does not require removal from the places of use and disposal. Cleaning of soils contaminated with oil and oil products has specific features and requires the use of agricultural techniques (loosening, moistening). The studies carried out have shown a change in the concentration of oil pollution in the soil from 40 % to 1–5 % of oil in the process of biodegradation after 3 months at positive temperatures.

Water-Gas Shift Reaction Produces Formate at Extreme Pressures and Temperatures in Deep Earth Fluids

<div> <div> <div> <div> <p>The water-gas shift reaction is one of the most important reactions in industrial hydrogen production and plays a key role in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle, but is little known at extreme pressure-temperature conditions found in Earth’s upper mantle. Here, we performed extensive ab initio molecular dynamics simulations and free energy calculations to study the water-gas shift reaction. We found the direct formation of formic acid from CO and supercritical water at 10∼13 GPa and 1400 K without any catalyst. Contrary to the common assumption that formic acid or formate is an intermediate product, we found that HCOOH is thermodynamically more stable than the products of the water-gas shift reaction above 3 GPa and at 1000∼1400 K. Our study suggests that the water-gas shift reaction may not happen in Earth’s upper mantle, and formic acid or formate may be an important carbon carrier in reducing environments, participating in many geochemical processes in deep Earth. </p> </div> </div> </div> </div>

Organobentonites Modified with Poly(Acrylic Acid) and Its Sodium Salt for Foundry Applications

The article aims to verify the possibility of obtaining an organic–inorganic material acting as both a binder and a lustrous carbon carrier in bentonite-bonded molding sands. Due to the wide industrial application, organoclays can be considered as innovative materials supporting the foundry technology in meeting environmental requirements. In this study, the organic modification of montmorillonite in calcium bentonite (SN) was performed by poly(acrylic acid) (PAA) and its sodium salt (PAA/Na). Additionally, for the purpose of comparison, the sodium-activated bentonite/poly(acrylic acid) (SN-Na/PAA) composites were also prepared. The collective analysis of the research results used in the assessment of the mineral/polymer interaction mechanism indicates surface adsorption combined with the intercalation of PAA monolayer into the mineral interlayer spaces. Materials were characterized by the combination of Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) methods. Based on the XRD analysis, the influence of PAA/Na on the aluminosilicate layered structure was found to be destructive, which may adversely affect the binding properties of SN/PAA/Na composites considered as a potential group of new foundry binders. The SN/PAA and SN-Na/PPA composites (with appropriate polymer content) can act as a binding agent in the synthetic molding sand technology, despite coating the bentonite particles with polymer molecules. The risk of losing the mineral′s binding capacity is reduced by the good binding properties of pol(acrylic acid) itself. The article is the first stage (preceding the thermal analysis and the strength tests of molding sands with the prepared organobentonites) in determining the possibility of obtaining a new full-value foundry binder in molding sands with bentonite.

Water Gas May Not Shift under Extreme Conditions of Pressure and Temperature

The water-gas shift reaction is a key reaction in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle, but is little known at extreme pressure-temperature conditions found in Earth’s upper mantle. Here, we performed extensive ab initio molecular dynamics simulations and free energy calculations to study the water-gas shift reaction. We found the direct formation of formic acid out of CO and supercritical water at 10∼13 GPa and 1400 K without any catalyst. Contrary to the common assumption that formic acid or formate is an intermediate product, we found that HCOOH is thermodynamically more stable than the products of the water-gas shift reaction above 3 GPa and at 1000∼1400 K. Our study suggests that the water-gas shift reaction may not happen in Earth’s upper mantle, and formic acid or formate may be an important carbon carrier, participating in many geochemical processes in deep Earth.<br>

Water Gas May Not Shift in Deep Earth

The water-gas shift reaction is a key reaction in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle, but is little known at extreme pressure-temperature conditions found in Earth’s upper mantle. Here, we performed extensive ab initio molecular dynamics simulations and free energy calculations to study the water-gas shift reaction. We found the direct formation of formic acid out of CO and supercritical water at 10∼13 GPa and 1400 K without any catalyst. Contrary to the common assumption that formic acid or formate is an intermediate product, we found that HCOOH is thermodynamically more stable than the products of the water-gas shift reaction above 3 GPa and at 1000∼1400 K. Our study suggests that the water-gas shift reaction may not happen in Earth’s upper mantle, and formic acid or formate may be an important carbon carrier, participating in many geochemical processes in deep Earth.<br>

Thermodynamic analysis of a Carbon Carrier Cycle (CCC) for low temperature heat recovery

The aim of the paper is to study the thermodynamic behavior of a non-conventional power cycle, named Carbon Carrier Cycle (CCC), which is expected to obtain interesting performance with low temperature heat source. The CCC may be regarded as derived from an absorption machine, where an expander replaces the condenser, the throttling valve and the evaporator. The working fluid is a mixture of CO2 and a proper absorber. In the paper, the thermodynamic model of this kind of cycles is described, and the results obtained considering Acetone as the absorber are discussed. A first performance comparison is then conducted with a more conventional Organic Rankine Cycle (ORC).

Water Gas May Not Shift in Deep Earth

The water-gas shift reaction is a key reaction in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle, but is little known at extreme pressure-temperature conditions found in Earth’s upper mantle. Here, we performed extensive ab initio molecular dynamics simulations and free energy calculations to study the water-gas shift reaction. We found the direct formation of formic acid out of CO and supercritical water at 10∼13 GPa and 1400 K without any catalyst. Contrary to the common assumption that formic acid or formate is an intermediate product, we found that HCOOH is thermodynamically more stable than the products of the water-gas shift reaction above 3 GPa and at 1000∼1400 K. Our study suggests that the water-gas shift reaction may not happen in Earth’s upper mantle, and formic acid or formate may be an important carbon carrier, participating in many geochemical processes in deep Earth.<br>