ACS Engineering AuPub Date : 2023-05-18DOI: 10.1021/acsengineeringau.3c00003
Benoit Rugabirwa*, Jean Népo Hakizimana, Abdul-Rauf Ibrahim, Yanzhen Hong, Yuzhong Su, Hongtao Wang and Jun Li*,
{"title":"Strategic CO2 Storage Material toward a Selective Control of Calcium Carbonate Polymorphs as Additives in Ester Oil Reinforcement","authors":"Benoit Rugabirwa*, Jean Népo Hakizimana, Abdul-Rauf Ibrahim, Yanzhen Hong, Yuzhong Su, Hongtao Wang and Jun Li*, ","doi":"10.1021/acsengineeringau.3c00003","DOIUrl":"10.1021/acsengineeringau.3c00003","url":null,"abstract":"<p >In the efforts to corroborate safer environmental CO<sub>2</sub> mitigation strategies, herein, we elucidate engineered practices that convert the absorbed CO<sub>2</sub> in a solid material and its utilization in the path of product synthesis. In this way, the cheaper lime material, the primary calcium resource, when exposed to CO<sub>2</sub> capture, and the storage material (CO<sub>2</sub>CSM) prepared by using 1,2-ethylenediamine and 1, 4-butanediol resulted in the formation of controlled vaterite and aragonite CaCO<sub>3</sub> polymorphs in their respective pure forms mediated by the functionalized CO<sub>2</sub>CSM. The investigation studies demonstrated that the obtained CO<sub>2</sub>CSM under the supercritical CO<sub>2</sub> state has a higher uptake and release efficiency of CO<sub>2</sub> equivalent to 3.730 and 3.17 mmol/g, respectively. Therefore, the conversion of raw materials depended on the amount of CO<sub>2</sub>CSM availed in the reaction and would be complete at the expense of supercritical CO<sub>2</sub>CSM in the solid-type reaction. The mechanism study explains the fundamental formation of products correlating to the amount of CO<sub>2</sub>CSM supplied in the reaction which would initiate the reaction, while the amine functional group of the material could stabilize and effectively control the transition of vaterite to aragonite phases of CaCO<sub>3</sub>. The so-obtained CaCO<sub>3</sub> phases were tested for their antiwear and friction stability of the lubricant 500SN; vaterite and aragonite demonstrated good reinforcement of the mechanical properties of lubricants compared to the calcite type. Therefore, this system proposes a validation platform of using sequestrated CO<sub>2</sub> to generate products with industrial commercialization benefits in the reinforcement of organic-based lubricants.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.3c00003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43539895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-05-14DOI: 10.1021/acsengineeringau.3c00007
Moshe Sheintuch*, Olga Nekhamkina and Leonid Tartakovsky,
{"title":"Heat Recuperation from Internal Combustion Engines by Fuel Reforming: Kinetics-Based Analysis","authors":"Moshe Sheintuch*, Olga Nekhamkina and Leonid Tartakovsky, ","doi":"10.1021/acsengineeringau.3c00007","DOIUrl":"10.1021/acsengineeringau.3c00007","url":null,"abstract":"<p >In an effort to estimate the feasibility of heat recuperation from an internal combustion engine (ICE) by steam reforming (SR) or by decomposition of the fuel, we study here the required size of a reformer heat exchanger in order to power a 3.7 kW engine. To that end, we experimentally test the heat transfer in a structured commercial reactor with ∼0.39 m<sup>2</sup> of heat transfer area in an ∼1 L unit. We then simulate the required length for evaporation and reforming of several fuels, using published kinetics with a highly active catalyst, under a fixed exhaust temperature of 973 K, and study the effect of pressure and steam-to-fuel ratio. Both co- and counter-current schemes are considered. Methanol decomposition is probably the best solution from the energy point of view. However, it is known to lead to deactivation. Methanol SR (with S/M = 1) requires about 2 L of reformer-HE and seems to be a reasonable solution, yielding a chemical energy gain of ∼16%, a value close to the asymptotic thermodynamic value. Moreover, the presence of CO<sub>2</sub> in the reformate is known to mitigate to NO<i><sub>x</sub></i> emissions down to zero-impact levels. Ethanol SR (with S/E = 1 or 3) yields poor results since CH<sub>4</sub> is an intermediate, which requires high temperatures for reforming; operating ESR requires exhaust temperatures of ∼1250 °K or higher. While such high temperatures may be attained and may yield an energetic gain of more than 20%, it will require modification of the process. Methylal SR (S/MA = 1) yields good results as well.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.3c00007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43816557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-05-13DOI: 10.1021/acsengineeringau.3c00006
Anga Hackula, Richard O’Shea, Jerry D. Murphy and David M. Wall*,
{"title":"Design, Construction, and Concept Validation of a Laboratory-Scale Two-phase Reactor to Valorize Whiskey Distillery By-products","authors":"Anga Hackula, Richard O’Shea, Jerry D. Murphy and David M. Wall*, ","doi":"10.1021/acsengineeringau.3c00006","DOIUrl":"10.1021/acsengineeringau.3c00006","url":null,"abstract":"<p >The by-products generated from the whiskey distillation process consist of organic liquids with a high chemical oxygen demand (COD) and residues with a high solid content. Low-carbon strategies that repurpose and valorize such by-products are now imperative to reduce the carbon footprint of the food and beverage industries. The operation of a two-phase anaerobic digester to produce volatile fatty acids (VFAs) and biogas may enable distilleries to transition toward a low-carbon bioeconomy. An example of such a system is a leach bed reactor connected to an expanded granular sludge bed (LBR-EGSB) which was designed, commissioned, and conceptually validated in this paper. Several design improvements progress the LBR-EGSB beyond previous reactor designs. An external gas–liquid–solid separator in the EGSB was used to capture any residual gases produced by the effluent and may reduce the amount of methane slippage and biomass washout. The implementation of a siphon-actuated leachate cup is a low-cost alternative that is less prone to actuation malfunction as compared to electrically actuated solenoid valves in previous reactor designs. Furthermore, replacing fresh water with distillery’s liquid by-products as leachate promotes a circular repurpose and reuse philosophy. The system proved to be effective in generating VFAs (10.3 g VFAs L<sup>–1</sup><sub>Leachate</sub>), in EGSB COD removal (96%), and in producing methane-rich biogas (75%<sub>vol</sub>), which is higher than the values achieved by traditional anaerobic digestion systems. The LBR-EGSB could ultimately provide more by-product valorization and decarbonization opportunities than traditional anaerobic digestion systems for a whiskey distillery.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.3c00006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10040334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-04-17DOI: 10.1021/acsengineeringau.2c00053
Abolfazl Alizadeh Sahraei, Dariush Azizi, Abdol Hadi Mokarizadeh, Daria Camilla Boffito* and Faïçal Larachi*,
{"title":"Emerging Trends of Computational Chemistry and Molecular Modeling in Froth Flotation: A Review","authors":"Abolfazl Alizadeh Sahraei, Dariush Azizi, Abdol Hadi Mokarizadeh, Daria Camilla Boffito* and Faïçal Larachi*, ","doi":"10.1021/acsengineeringau.2c00053","DOIUrl":"10.1021/acsengineeringau.2c00053","url":null,"abstract":"<p >Froth flotation is the most versatile process in mineral beneficiation, extensively used to concentrate a wide range of minerals. This process comprises mixtures of more or less liberated minerals, water, air, and various chemical reagents, involving a series of intermingled multiphase physical and chemical phenomena in the aqueous environment. Today’s main challenge facing the froth flotation process is to gain atomic-level insights into the properties of its inherent phenomena governing the process performance. While it is often challenging to determine these phenomena via trial-and-error experimentations, molecular modeling approaches not only elicit a deeper understanding of froth flotation but can also assist experimental studies in saving time and budget. Thanks to the rapid development of computer science and advances in high-performance computing (HPC) infrastructures, theoretical/computational chemistry has now matured enough to successfully and gainfully apply to tackle the challenges of complex systems. In mineral processing, however, advanced applications of computational chemistry are increasingly gaining ground and demonstrating merit in addressing these challenges. Accordingly, this contribution aims to encourage mineral scientists, especially those interested in rational reagent design, to become familiarized with the necessary concepts of molecular modeling and to apply similar strategies when studying and tailoring properties at the molecular level. This review also strives to deliver the state-of-the-art integration and application of molecular modeling in froth flotation studies to assist either active researchers in this field to disclose new directions for future research or newcomers to the field to initiate innovative works.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/23/16/eg2c00053.PMC10288516.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9714560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hydrometallurgical Processing of Chalcopyrite by Attrition-Aided Leaching","authors":"Amine Dakkoune, Florent Bourgeois, Adeline Po, Catherine Joulian, Agathe Hubau, Solène Touzé, Carine Julcour*, Anne-Gwénaëlle Guezennec and Laurent Cassayre, ","doi":"10.1021/acsengineeringau.2c00051","DOIUrl":"10.1021/acsengineeringau.2c00051","url":null,"abstract":"<p >We report the investigation of a chalcopyrite leaching process that implements millimeter-sized glass beads that are stirred in the leach reactor to combine particle grinding, mechanical activation, and surface removal of reaction products. The paper focuses on demonstrating the impact of the so-called attrition-leaching phenomenon on the leaching rate of a chalcopyrite concentrate and provides a first understanding of the underlying mechanisms. For this purpose, we have compared the copper leaching yield for different configurations under controlled chemical conditions (1 kg of glass beads and 84 g of chalcopyrite concentrate in 2.5 L of H<sub>2</sub>SO<sub>4</sub>-H<sub>2</sub>O solution, pH = 1.3, <i>E</i><sub>h</sub> = 700 mV vs SHE, and <i>T</i> = 42 °C). On top of elemental analysis of the leach solution with time, we provide a full characterization of the solid residue based on X-ray diffraction, elemental analysis, and sulfur speciation. We demonstrate that glass beads led to a remarkable enhancement of the leaching rate in conditions where particles were already passivated by simple leaching and even when large amounts of solid products (elemental sulfur and jarosite) were present. An in-depth evaluation of particle size distribution showed that particle breakage occurred during a rather short time (a few hours) at the beginning of the runs, transforming the initial particles with <i>d</i><sub>4/3</sub> = 30 μm to finer particles with <i>d</i><sub>4/3</sub> = 15 μm. Then, particle breakage almost stopped, while an attrition phenomenon was evidenced, inducing the formation of very fine particles (<1 μm) and aggregates concomitantly with copper leaching.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.2c00051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41296529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-02-28DOI: 10.1021/acsengineeringau.2c00052
Joseph C. Gebers*, Abu Farhan Bin Abu Kasim, George J. Fulham, Kien Yi Kwong and Ewa J. Marek*,
{"title":"Production of Acetaldehyde via Oxidative Dehydrogenation of Ethanol in a Chemical Looping Setup","authors":"Joseph C. Gebers*, Abu Farhan Bin Abu Kasim, George J. Fulham, Kien Yi Kwong and Ewa J. Marek*, ","doi":"10.1021/acsengineeringau.2c00052","DOIUrl":"10.1021/acsengineeringau.2c00052","url":null,"abstract":"<p >A novel chemical looping (CL) process was demonstrated to produce acetaldehyde (AA) via oxidative dehydrogenation (ODH) of ethanol. Here, the ODH of ethanol takes place in the absence of a gaseous oxygen stream; instead, oxygen is supplied from a metal oxide, an active support for an ODH catalyst. The support material reduces as the reaction takes place and needs to be regenerated in air in a separate step, resulting in a CL process. Here, strontium ferrite perovskite (SrFeO<sub>3−δ</sub>) was used as the active support, with both silver and copper as the ODH catalysts. The performance of Ag/SrFeO<sub>3−δ</sub> and Cu/SrFeO<sub>3−δ</sub> was investigated in a packed bed reactor, operated at temperatures from 200 to 270 <sup>°</sup>C and a gas hourly space velocity of 9600 h<sup>–1</sup>. The CL capability to produce AA was then compared to the performance of bare SrFeO<sub>3−δ</sub> (no catalysts) and materials comprising a catalyst on an inert support, Cu or Ag on Al<sub>2</sub>O<sub>3</sub>. The Ag/Al<sub>2</sub>O<sub>3</sub> catalyst was completely inactive in the absence of air, confirming that oxygen supplied from the support is required to oxidize ethanol to AA and water, while Cu/Al<sub>2</sub>O<sub>3</sub> gradually got covered in coke, indicating cracking of ethanol. The bare SrFeO<sub>3−δ</sub> achieved a similar selectivity to AA as Ag/SrFeO<sub>3−δ</sub> but at a greatly reduced activity. For the best performing catalyst, Ag/SrFeO<sub>3−δ</sub>, the obtained selectivity to AA reached 92–98% at yields of up to 70%, comparable to the incumbent Veba-Chemie process for ethanol ODH, but at around 250 <sup>°</sup>C lower temperature. The CL-ODH setup was operated at high effective production times (i.e., the time spent producing AA to the time spent regenerating SrFeO<sub>3−δ</sub>). In the investigated configuration with 2 g of the CLC catalyst and 200 mL/min feed flowrate ∼5.8 vol % ethanol, only three reactors would be required for the pseudo-continuous production of AA via CL-ODH.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.2c00052","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9714557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-02-15DOI: 10.1021/acsengineeringau.3c00001
Vivek V. Ranade*, and , Linda J. Broadbelt*,
{"title":"Welcome to Volume 3 of ACS Engineering Au","authors":"Vivek V. Ranade*, and , Linda J. Broadbelt*, ","doi":"10.1021/acsengineeringau.3c00001","DOIUrl":"10.1021/acsengineeringau.3c00001","url":null,"abstract":"","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.3c00001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43957572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-02-06DOI: 10.1021/acsengineeringau.2c00050
Namrata Gaikwad, Hyunho Kim, Gaurav Bhattacharjee, Jitendra S Sangwai, Rajnish Kumar* and Praveen Linga*,
{"title":"Thermodynamics, Kinetics, Morphology, and Raman studies for sH Hydrate of Methane and Cyclooctane","authors":"Namrata Gaikwad, Hyunho Kim, Gaurav Bhattacharjee, Jitendra S Sangwai, Rajnish Kumar* and Praveen Linga*, ","doi":"10.1021/acsengineeringau.2c00050","DOIUrl":"10.1021/acsengineeringau.2c00050","url":null,"abstract":"<p >Natural gas is expected to be the major energy source in the near future, and storing it in the form of gas hydrate is a safe, clean, and economical approach. However, required thermodynamic conditions and slow kinetics are the key challenges that need to address for process viability. This study involves an experimental investigation of methane and cyclooctane sH hydrate formation for possible applications in gas storage using thermodynamics, kinetics, morphology, and Raman analysis. The hydrate formation is carried out at such thermodynamic conditions where only sH hydrate would form. The four-phase (L<sub>w</sub>-L<sub>HC</sub>-H-V) sH hydrate equilibrium is studied for the methane and cyclooctane system via dissociation along the phase boundary method which is a robust method as it delivers a greater number of equilibrium data points in a single experimental run compared to other available methods. The sH hydrate formation helps in lowering the equilibrium conditions compared with sI hydrate formation. The slow sH hydrate formation kinetics can be improved by using low tryptophan concentrations. In this work, 0.1 wt % is the optimum tryptophan concentration as the gas uptake, and the hydrate formation rate is found to be the highest compared to 0.01, 0.05, and 1 wt % tryptophan concentrations. Here, we also visually investigate the sH hydrate formation and observed that the hydrate formation occurs below the interface for the system with no tryptophan; however, hydrate formation occurrence above the interface increases with an increase in the tryptophan concentration. The increase in the hydrate formation could be dedicated to the increased gas uptake due to the increasingly porous nature of hydrate formation. The Raman analysis confirmed the presence of methane and cyclooctane in sH hydrate cages. The higher intensity of the peaks using tryptophan additionally confirms the higher hydrate formation compared to the system with no tryptophan.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.2c00050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46868608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Solid Phase Macromixing Study in a Pilot-Scale Geldart Group B Circulating Fluidized Bed Riser Using Single Particle RTD and RPT Measurements","authors":"Trilokpati Tribedi, Pankaj Tiwari, Harish Jagat Pant and Rajesh Kumar Upadhyay*, ","doi":"10.1021/acsengineeringau.2c00049","DOIUrl":"10.1021/acsengineeringau.2c00049","url":null,"abstract":"<p >Solid flow in a Geldart’s group B circulating fluidized bed (CFB) riser is complex, and it exhibits backflow and recirculation in the riser. A single radioactive tracer particle is used to measure the overall and sectional residence time distribution in a CFB riser at a gas velocity of 7.6–9.2 m/s and a solid flux of 100–200 kg/m<sup>2</sup>s. At the same time, radioactive particle tracking (RPT) data are used to measure the trajectories of the tracer particle and its length distribution at the bottom and middle sections of the riser. Both residence time distribution (RTD) and trajectory length distribution data obtained from RPT and RTD experiments are processed and compared. Results show that the bottom section has higher back mixing than the middle section. The results also show that back mixing in both the sections reduces with an increase in the gas inlet velocity and reduces marginally with an increase in the solid flux. Results confirm that RPT and RTD data are highly correlated and can be used with the same accuracy to quantify the macromixing behavior of any process vessel/reactor.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.2c00049","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44105459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ACS Engineering AuPub Date : 2023-01-23DOI: 10.1021/acsengineeringau.2c00043
Jimmy K. Soeherman, Andrew J. Jones and Paul J. Dauenhauer*,
{"title":"Overcoming the Entropy Penalty of Direct Air Capture for Efficient Gigatonne Removal of Carbon Dioxide","authors":"Jimmy K. Soeherman, Andrew J. Jones and Paul J. Dauenhauer*, ","doi":"10.1021/acsengineeringau.2c00043","DOIUrl":"10.1021/acsengineeringau.2c00043","url":null,"abstract":"<p >Atmospheric carbon poses an existential threat to civilization via global climate change. Hundreds of gigatonnes of carbon dioxide must be removed from earth’s atmosphere in the next three decades, necessitating a low-cost, energy-efficient process to extract low concentrations of carbon dioxide for conversion to a stable material permanently stored for thousands of years. In this work, the challenge of removing gigatonnes of CO<sub>2</sub> is described via the scale of effort and the thermodynamics of collecting and reducing this diffuse chemical, the accumulation of which imparts a substantial entropy penalty on any atmospheric carbon capture process. The methods of CO<sub>2</sub> reduction combined with upstream direct air capture (DAC) including absorption, membrane separation, and adsorption are compared with biomass torrefaction and permanent burial (BTB). A Monte Carlo model assesses the mass, energy, and economics of the full process of biomass torrefaction from biomass collection and transport to stable carbon burial to determine that 95% of scenarios could remove carbon for less than $200 per CO<sub>2</sub>-tonne-equivalent. Torrefied carbon is further discussed for its long-term stability and availability at the scale required to substantially mitigate the threat of climate change.</p>","PeriodicalId":29804,"journal":{"name":"ACS Engineering Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsengineeringau.2c00043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44726064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}