Carbon Technologies Research Articles

The Universal Classification system for assessing the embodied carbon of concrete in Canada

Concrete is known to be the most prevalent human-made material globally owing to its durability, versatility and affordability which; however, contributes significantly to global CO2 emissions. Consequently, efforts have intensified to reduce concrete's embodied carbon, with emerging or conventional alternative technologies aiming to mitigate emissions and produce "sustainable" and "low carbon" concrete; a set of terms which have been used inconsistently leading to potential greenwashing and confusion in the industry. Simultaneously, there is a pressing need for tools and policies to guide the design of low-carbon concrete structures and infrastructure. This paper introduces an embodied carbon classification system as a practical solution to address industry confusion and facilitate sustainable practices in the concrete construction sector. It consists of a universally applicable tool that can be used by designers, manufacturers, asset owners and policy makers to enable a robust evaluation of the embodied carbon concrete, develop pathways to concrete decarbonisation.

Preparation of high-value carbon nanotubes from real waste plastic towards the negative carbon technology

The preparation of carbon nanotubes (CNTs) from plastics is of great significance for realizing high value utilization of waste and reducing carbon emission. Here, several kinds of real waste plastics were introduced into catalytic pyrolysis, and the process was also optimized. The results showed that the presence of impurities (e.g., adhesive labels) reduced the initial activation energy of the pyrolysis reaction, and the pyrolysis process was extended and could be divided into two stages. During the catalytic process, impurities play a toxic role on the catalyst at higher temperatures and result in the agglomeration of catalyst particles and a decrease in catalytic activity. Less than 10 wt.% carbon fibers were collected from milk cup waste. However, after experimental optimization, the influence of the impurity component was greatly reduced. The toxic effect of organic impurity volatiles on a catalyst was avoided by employing a segmented catalytic pyrolysis process, which led to an increase in solid carbon content of more than 20 % for express package waste. Simultaneously, more uniform and smoother CNTs can be found in the obtained solid carbon. The process of preparing carbon nanotubes with higher yield and better quality is feasible and has important application prospects in the utilization of waste plastics.

A Study on the Potential and Cost of Carbon Reduction from Low Carbon Technologies in the Chinese Copper Industry

A Study on the Potential and Cost of Carbon Reduction from Low Carbon Technologies in the Chinese Copper Industry

Scientific advances regarding the effect of carbonated alkaline waste materials on pozzolanic reactivity

Using alkaline waste materials as biomass ash (BA), Recycled Concrete Fines (RCF) from constructions and demolition waste (CDW) and ladle furnace slags (LFS), as CO2 massive sinks worldwide through the generation of new potential SCM by Accelerated Carbonation Technologies to reduce the cement industry's carbon footprint is increasingly attracting attention for its environmental benefits and the materials' improved performance in blended cement matrices. This paper employs characterization and identification techniques (XRF, XRD–Rietveld, SEM/EDX, BET, TG/DTG, FTIR, NMR) to analyse the effect of accelerated carbonation of white ladle furnace slag, siliceous construction and demolition waste and biomass ash on those materials' physical and mineralogical properties, their chemical reactivity and their pozzolan/lime systems' mineralogical phases. The results show that although behaviour differs depending on the carbonated waste materials' alkalinity, all three present notable increases in BET surface area (7–17.5 m2/g) and substantially altered potentially carbonatable mineralogical phases (e.g. portlandite, Ca-olivine, periclase, hydrated cement phases), which mostly transition towards calcite, due to the CO2 uptake. Thermodynamic modelling of the pozzolanic reaction indicates that CSH/C(A)SH) gels are the most stable phases, followed by ettringite, C4AH13 and C4AcH12.

Fuzzy set-based decision support system for hydrogen sulfide removal technology selection in natural gas processing: a sustainability and efficiency perspective.

Removing hydrogen sulfide (H2S) toxic and corrosive gas from the natural gas processing and utilization industry is a challenging problem for managers of these industries. This problem involves different economic, environmental, and health issues. Various technologies have been employed to remove the H2S gas from these industries, and choosing appropriate H2S removal technologies is a complex multi-criteria decision-making (MCDM) problem. In this regard, the present research work aims at developing a novel decision support system (DSS) by integrating MCDM techniques based upon the (best worst method) BWM and (alternative ranking order method accounting for two-step normalization) AROMAN methods under the decomposed fuzzy set theory. The DSS is used to assess technologies for removing H2S gas and then choose the best scenario for implementing among these technologies. Fourteen criteria in four environmental, social, economic, and efficiency aspects and five technologies of fixed-bed activated carbon technology (A_h2s1), biotrickling filter technology (A_h2s2), scavenger technology (A_h2s3), chemical oxidation scrubber technology (A_h2s4), and liquid redox technology (A_h2s5) have been chosen for evaluation. The final value of each technology is obtained as A_h2s1 (0.5550), A_h2s2 (0.5262), A_h2s3 (0.5809), A_h2s4 (0.6357), and A_h2s5 (0.5790). The results reveal that the chemical oxidation scrubber technology (A_h2s4) and biotrickling filter technology (A_h2s2) with the values of 0.6357 and 0.5262 are respectively the best and worst scenario for the removal of H2S produced by the natural gas processing and utilization plants of Iran. Therefore, the DSS is feasible and applicable and gives reliable and robust findings for acquiring the optimal H2S removal technology.

Field investigation on the performance of low-carbon MgO-carbonated composite piles for ground treatments

Carbonation technology using MgO and CO2 has been considered a rapid, effective, and environmentally friendly method for improving weak soils, mainly applied in shallow foundation treatments. This study introduced a novel MgO-carbonated composite pile (MCP) technique developed by injecting CO2 through a gas-permeable pipe pile into a MgO-mixing column for carbonation and solidification and its applications in weak subgrade treatments. Several field tests were carried out to study the characteristics of MCP as well as the performance of the MCP-reinforced foundations, including carbonation reaction temperature monitoring, pore-water pressure monitoring, standard penetration tests (SPT), unconfined compressive strength (UCS) tests, static load tests, and subgrade deformation monitoring. Results showed vigorous and uniform carbonation within the MgO-mixing column, confirming the feasibility of constructing large-diameter MgO-mixing columns. The distribution, evolution, and affected zone of excess pore-water pressure induced by MCP installation were determined. The MCP exhibited good pile quality, with average SPT-N and UCS values of 39 and 1021 kPa, respectively. MCP’s bearing capacity was superior to pre-stressed high-strength concrete pipe piles, with ultimate vertical and lateral bearing capacities of 1920 kN and 119 kN, respectively. The MCP-reinforced foundation exhibited a small settlement of 54.5 mm under embankment loads. Life cycle assessment indicated significant carbon reduction benefits for MCP, with 44.7% lower carbon emissions compared to traditional composite piles.

Assessing robust policies for the adoption of low-carbon technologies under uncertainty

Increasing the adoption of alternative technologies is vital to ensure a successful transition to net-zero emissions in the manufacturing sector. However, existing models are limited in their ability to analyse technology adoption and the impact of policy interventions in generating sufficient demand to reduce cost in the face of uncertainty. Such a model is vital for assessing policy-instruments for the implementation of future uncertain energy scenarios. We formulate a novel robust market potential assessment problem under uncertainty to support low carbon technology adoption, resulting in policies that are more immune to uncertain factors. We demonstrate two case studies: the potential use of carbon capture and storage for iron and steel production across the EU, and the transition to hydrogen from natural gas in steam boilers across the chemicals industry in the UK. We show that when parameters are jointly 5% uncertain, the robust policy for CCUS adoption results in a 40% increase in cost. Each robust optimisation problem is solved using an iterative cutting planes algorithm which enables existing models to be solved under uncertainty. By taking advantage of parallelisation we are able to solve the nonlinear robust market assessment problem for technology adoption in times within the same order of magnitude as the nominal problem. Our model demonstrates the possibility of locating robust policies for the implementation of low-carbon technologies, as well as providing direct insights for policy-makers into the decrease in policy effectiveness that results from increasing robustness. The approach we present is extensible to a large number of alternative technology adoption problems under uncertainty.

Spontaneous Phase Transition and Multistage Interfacial Mechanical Friction of Liquid Metals Induced CO2 Reduction at Room Temperature

AbstractExcessive emissions of carbon dioxide (CO2) have caused the greenhouse effect and environmental crisis. Therefore, the carbon reduction and negative carbon technologies are particularly important. Among these, the negative carbon technologies that convert CO2 into carbon materials or carbon‐based chemicals for reuse have attracted significant attention. However, the strong double covalent bonds make the CO2 conversion usually require harsh conditions, complex processes, and high energy consumption. Gallium‐based liquid metals (LMs) are the functional materials with both metallic and liquid properties, exhibiting a unique liquid‐phase structure and diverse surface characteristics. Herein, a strategy for reducing CO2 is proposed to carbon materials by utilizing the spontaneous phase transition and mechanical friction of liquid metals. The gallium (Ga) and indium (In) particles are mixed and exposed to CO2, the contact interface of metal particles spontaneously transforms into liquid metals. The system has multistage interfaces, including Ga/In, Ga/eGaIn, and In/eGaIn, capable of generating triboelectrification upon mechanical stimulation, leading to charge transfer. The high electric field generated by friction at the contact interface directly reduces CO2 to carbon materials at room temperature. The carbon materials cover the surface of eGaIn and can be directly stripped for used as fuel, or industrial applications.

Honeycomb-like porous carbons derived from multistep pyrolysis of artificial humic acids as efficient sorbents for removing diethyl phthalate

The uprecycling of hydrothermal liquid waste-derived artificial humic acids into stable carbon materials is helpful for advancing the development of hydrothermal carbonization technology, but it has rarely been investigated. For the first time, a multistep pyrolysis method was designed to convert artificial humic acids into honeycomb-like porous carbons (PCs). The obtained PCs exhibited a high specific surface area, reaching 1728.55 m2/g, while nonactivation treatment still provided a high value of 1425.14 m2/g. The hightemperature pyrolysis process yielded graphite-like structures and maintained surface functional groups. PCs have been applied as sorbents to remove the emerging plasticizer diethyl phthalate (DEP) in water environments and exhibit promising sorption capabilities (as high as 993.30 mg/g), which are much higher than those reported for other sorbents. The sorption rate was controlled by mass transfer and chemical-like sorption, whereas the sorption capability was controlled mainly by the adsorption process, especially pore filling. Partitioning, hydrogen bonding, pore filling and π–π stacking are possible sorption mechanisms. In addition to the specific surface area, the pore volume is a suitable parameter for assessing the sorption capability. Exogenous dissolved organic matter can affect the sorption of DEP onto PCs through cosorption and coverage of their surface, but its influence is limited. Excellent sorption performance can cover a wide range of pH conditions. The prepared PCs also showed notable reusability and practicality. In this study, an excellent method was proposed for recycling hydrothermal liquid waste and preparing PCs, and the prepared PCs exhibited great potential for environmental remediation.

Oyster shell based indirect carbonation integrated with probiotic encapsulation.

Recycling oyster shells-an abundant industrial waste-is essential to reduce marine pollution. Indirect carbonation is promising; however, is cost-prohibitive. This study is a pioneering endeavor to merge indirect carbonation and probiotic encapsulation technologies using oyster shells. Probiotics were encapsulated in the CaCO3 produced through indirect carbonation with oyster shells, and the performance was evaluated. Confocal laser scanning microscopy certified the survival of a substantial proportion of the encased probiotics. Importantly, the majority of the enveloped probiotics demonstrated robust survivability while passing through gastrointestinal and bile fluids. These findings underscore the applicability of oyster shells as an optimal precursor for probiotic encapsulation which is eco-friendly and addresses the challenges faced in industrial waste recycling. This novel approach overcomes the economic limitations associated with indirect carbonation and mitigates the shortcomings of existing probiotic encapsulation methods. Convergence of indirect carbonation and probiotic encapsulation technologies can chart new routes for the environmental sector.

Construction of carbon emission evaluation methods and indicators for low-carbon technologies in buildings

Global climate change is an increasingly prominent issue, with the building stock significantly to carbon emissions (CEs). Evaluating the effectiveness of renewal pathways and technologies is essential for carbon reduction in this domain. This study adopts theoretical research, field investigations, simulation analysis, and mathematical calculations, and innovatively integrates whole life-cycle evaluation with inventory methods. The carbon emissions reduction (CER) evaluation boundary of low carbon technologies (LCTs) is defined as the pre- and post-application operational stages and technology application stage. A novel comprehensive CER efficiency (CERE) indicator is established, combining the CER with embodied carbon payback time (ECPT), in addition to recommendations for the selection of evaluation criteria based on diverse building requirements. Simulations and calculations for four commonly used LCTs in Chongqing revealed that CERE provides a more holistic evaluation of CER effectiveness than traditional indicators, and identified a suite of LCTs suitable for Chongqing, encompassing replacement of energy-efficient lamps, roof photovoltaics and air source heat pumps. The findings provide a scientific basis for guiding the application of LCTs, renewal pathways and decarbonization management policy formulation in the building sector.

Removal of cefuroxime from aqueous solution by biochars derived from antibiotic mycelial residue.

In China, antibiotic mycelial residue is categorized as hazardous waste. To achieve the harmless and resourceful disposal of cephalosporin, three types of biochars from cephalosporin mycelia residues, namely non-activated carbon (BC1), ZnCl2-activated carbon (BC2), and KOH-activated carbon (BC3), were respectively fabricated by high-temperature pyrolysis carbonization technology. These three kinds of biochars were characterized via iodine value, FTIR, and SEM, and the adsorption performance of the prepared biochars was investigated using cefuroxime (CXM) as the adsorption target. The results indicated that BC3 biochar possesses the most well-developed pores and the highest iodine value of 1367.41 mg/g; The most suitable dosage is 1.6 g/L, and the lower the pH, the more favorable the adsorption effect. The investigation of adsorption kinetics revealed that it conformed to the kinetic model of pseudo-second order, as well as the process of adsorption was governed by the chemical adsorption mechanism, the rate of adsorption was affected by the collective impact of the quantity of active sites present and the interaction strength between the CXM molecules and the biochar. The exploration of adsorption thermodynamics revealed that it aligned with the Langmuir model, the surface of biochar was relatively uniform, and the adsorption was mainly of low coverage; The calculation of thermodynamic parameters demonstrated that the adsorption was exothermic and spontaneous.

Construction of a 3D spider web structure with spherical Ho2O3 wrapped by carbon nanofibers for high-efficiency microwave absorption and corrosion protection

Reasonable composition control and microstructure design are the effective ways to realize multi-functional high-performance absorbing materials. In this work, a three-dimensional (3D) spider web structure was designed by the electrospinning and high temperature carbonization technology, where Ho2O3 spheres were wrapped by carbon nanofibers. Herein, the spherical Ho2O3 were surrounded by layers of carbon nanofibers (spider silk), which were like the preys inside the spider's web. This unique bionic structure working in conjunction with the tuned components enables the as-prepared composites with improved impedance matching and enhanced loss capacity. The superior electromagnetic wave absorption performance was obtained as the minimum reflection loss of −61.37 dB at 2.90 mm and the maximum effective absorption bandwidth of 6.88 GHz (11.12–18 GHz) at 2.64 mm. At a thickness of 3.44 mm, the effective absorption bandwidth is 4.80 GHz (8–12.80 GHz), covering the entire X-band. At the same time, the composite soaked in the corrosive medium for 7 days owns a low corrosion current density (10−4 ∼10−6 A cm−2) and a high polarization resistance (105∼107 Ω), which exhibits the obvious anticorrosion ability. This work designs a specific spider web structure with high-performance microwave absorption and corrosion protection.

Unlocking the potential: Insights from industry on barriers, solutions and policy gaps in Ireland's energy storage sector

The energy storage sector across Europe faces many financial, regulatory and policy barriers which has to date hindered development in many countries. This study documents industry perspectives from Ireland, a country which requires a significant increase in the development of energy storage due to security of supply concerns, its isolation from Europe’s central transmission network and its reliance on wind energy as a primary intermittent renewable energy resource. Using focus groups and a survey with the renewable energy and storage sector, we document perspectives on the critical barriers, innovative solutions and policy gaps identified by industry stakeholders and policy makers. Our participants believe energy storage will play a crucial role in unlocking Ireland’s substantial wind energy potential in order to meet its energy security and climate aspirations. However, our respondents suggest that unlocking this potential will require a coherent national energy storage strategy designed to reduce curtailment, identify storage technologies with duration-specific targets and establish a more comprehensive renewable energy plus storage power procurement mechanism designed for the Irish market which supports the grid, rewards low carbon technologies and reduces emissions.

Bibliometric and Visual Analyses of Low Carbon Technology Innovations: Developments, Hotspots, and Trends

Bibliometric and Visual Analyses of Low Carbon Technology Innovations: Developments, Hotspots, and Trends

Carbonized seawater cement slurries for offshore deep cement mixing: Carbonation mechanism, strength enhancement and microstructure evolution

Seawater cement slurry (SCS) is a commonly used binder in offshore deep cement mixing (DCM) construction. Seawater cement slurries are usually prepared before they are grouted into the seabed and mixed with marine clay. The aim of this study is to explore the feasibility of applying carbonation technology to fabricate SCS suitable for offshore DCM while achieving carbon sequestration and obtaining better mechanical properties for stabilised marine sediments.This study demonstrated that after appropriate carbonation, carbonized SCS can be used in DCM to replace conventional SCS. Short-term carbonation promotes cement dissolution and hydration rates under seawater conditions rich in magnesium, calcium, and other inorganic ions. The carbonates include calcite, vaterite and amorphous carbonates, which provide additional nucleation sites for the hydration of SCS, resulting in an increment for amorphous CS(A)H gel with a dense pore structure and binding interaction with soil particles. After carbonation with 20 % CO2 for 5 min (0.5 wt% of cement), the UCS and secant modulus of cement-soil mixtures by 15.7 % and 111 % at the age of 1 day, and by 6.82 % and 10 % at the age of 28 days when treating marine clay with 80 % moisture content at a dosage of 260 kg/m3.

Investigating the Future of Freight Transport Low Carbon Technologies Market Acceptance across Different Regions

Fighting climate change has become a major task worldwide. One of the key energy sectors to emit greenhouse gases is transportation. Therefore, long term strategies all over the world have been set up to reduce on-road combustion emissions. In this context, the road freight sector faces significant challenges in decarbonization, driven by its limited availability of low-emission fuels and commercialized zero-emission vehicles compared with its high energy demand. In this work, we develop the Mobility and Energy Transportation Analysis (META) Model, a python-based optimization model to quantify the impact of transportation projected policies on freight transport by projecting conventional and alternative fuel technologies market acceptance as well as greenhouse gas (GHG) emissions. Along with introducing e-fuels as an alternative refueling option for conventional vehicles, META investigates the market opportunities of Mobile Carbon Capture (MCC) until 2050. To accurately assess this technology, a techno-economic analysis is essential to compare MCC abatement cost to alternative decarbonization technologies such as electric trucks. The novelty of this work comes from the detailed cost categories taken into consideration in the analysis, including intangible costs associated with heavy-duty technologies, such as recharging/refueling time, cargo capacity limitations, and consumer acceptance towards emerging technologies across different regions. Based on the study results, the competitive total cost of ownership (TCO) and marginal abatement cost (MAC) values of MCC make it an economically promising alternative option to decarbonize the freight transport sector. Both in the KSA and EU, MCC options could reach greater than 50% market shares of all ICE vehicle sales, equivalent to a combined 35% of all new sales shares by 2035.

Selective Catalytic Reduction of Nitrogen Oxides with Hydrogen (H2‐SCR‐DeNOx) over Platinum‐Based Catalysts

AbstractSelective catalytic reduction of NOx with hydrogen (H2‐SCR‐DeNOx) is applied among other techniques (i. e., SCR‐DeNOx by applying NH3 or hydrocarbons as reducing agents) to control nitrogen oxides from mobile and stationary sources. As a zero carbon technology, which efficiently reduces NOx below 200 °C, H2‐SCR‐DeNOx has gained attention in installations and plants with H2 availability. The catalytic properties of platinum‐based catalysts with the main focus on the applied supports (i. e., inorganic oxides and zeolites) are given in detail. Another focus concerns on how the feed composition affects catalytic properties, specifically the levels of oxygen, water vapor, sulfur, and carbon oxides present in the exhausts. The major challenges are presented in enhancing the N2 selectivity and stability of catalysts at low temperatures without affecting their activity. Promising research prospects in this area include the development of catalysts with improved dispersion and distribution of Pt particles. In addition, the proposed bi‐functional (dual‐function) reaction mechanism over Pt‐containing catalysts, together with the adsorption/dissociation mechanism and NO oxidation/reduction mechanism, is described and critically reviewed. Also, Pd‐based catalysts are briefly discussed. It is expected that the review will provide broad insights into the design and optimization of catalysts in the H2‐SCR‐DeNOx.

Research on provincial implied carbon emissions in China under the shared responsibility driven by new quality productivity: A new approach

The allocation of responsibility for carbon emissions among involved parties has garnered significant attention. This study proposes a comprehensive sharing coefficient methodology known as CVAT (direct carbon emissions, value added, and technology level) to enhance the accuracy and equity of responsibility sharing driven by the new productivity standard. This study utilizes the environmental expansion multi-region input-output (EEMRIO) model to assess China's implicit provincial carbon emissions over the previous two decades. The study investigates the characteristics of the implied carbon transfer network using social network analysis (SNA) techniques. Key findings include: (1) The CVAT method's determination of responsibility sharing coefficients aligns with fairness and efficiency principles, resulting in a more equitable distribution of implied carbon emission responsibilities conducive to achieving fair carbon emission reduction. (2) Over the research period, national implied carbon emissions exhibited an upward trajectory, increasing from 3.305 billion tons in 2002 to 9.726 billion tons in 2017, with Shandong, Hebei, and Jiangsu provinces ranking among the top emitters in China. (3) Eastern coastal and western regions function as net carbon transfer out regions, while the central, northeast, and southwest regions act as net carbon transfer in regions. (4) The implied carbon transfer network demonstrated relative stability throughout the study period, with Shandong, Hebei, Jiangsu, and Inner Mongolia emerging as major carbon transfer provinces. The study's outcomes hold significant implications for the impartial and accurate assessment of carbon emission responsibilities and the advancement of global carbon emission reduction efforts.

Empowering energy access: Exploring financial inclusion's impact on energy poverty in the fragile five economies

Energy poverty is a major issue that deepens economic challenges, especially in the five fragile states of Turkey, Brazil, South Africa, India, and Indonesia. The objective of this study is to examine the impact of financial inclusion on energy poverty, as removing financial barriers to energy access and utilisation is critical for sustainable development. The study hypothesizes that financial inclusion plays a decisive role in alleviating energy poverty. The study analyses the second generation panel methods such as AMG, Driscool-Kraay, and FMOLS using annual data from 2000 to 2021 and examines the causal relationships between variables using Dumitrescu-Hurlin panel causality test. The findings reveal that financial inclusion, low carbon technology trade, energy efficiency, economic growth, and human capital play a central role in alleviating energy poverty in these economies. On the other hand, a unidirectional causal relationship was found between financial inclusion and low carbon technology trade, human capital, energy efficiency, and energy poverty. In contrast, a bidirectional causal relationship was observed between economic growth and energy poverty. These findings provide important insights for policymakers and stakeholders; understanding the complex dynamics between financial inclusion and energy poverty can help design targeted strategies to increase energy access and promote inclusive economic development in fragile economies.