Bicarbonate Production Research Articles

Copper (II)-catalyzed polydopamine mediated photothermal sensors for visual quantitative point-of-care testing

BackgroundTemperature sensing is commonly used in point-of-care (POC) detection technologies, yet the portability and convenience of use are frequently compromised by the complexity of thermosensitive processes and signal transduction. Especially, multi-step target recognition reactions and temperature measurement in the reaction vessel present challenges in terms of stability and integration of detection devices. To further combine photothermal reaction and signal readout in one assay, these two processes enable to be integrated into miniaturized microfluidic chips, thereby facilitating photothermal sensing and achieving a simple visual temperature sensing as POC detection. ResultsA copper ion (Cu2+)-catalyzed photothermal sensing system integrated onto a microfluidic distance-based analytical device (μDAD), enabling the visual, portable, and sensitive quantitative detection of multiple targets, including ascorbic acid, glutathione, and alkaline phosphatase (ALP). The polydopamine nanoparticles (PDA NPs) were synthesized by the regulation of free Cu2+ through redox or coordination reactions, facilitating the transduction of distinct photothermal response signals and providing the versatile Cu2+-responsive sensing systems. Promoted by integration with a photothermal μDAD, the system combines PDA's photothermal responsiveness and thermosensitive gas production of ammonium bicarbonate for improved sensitivity of ALP detection, reaching the detection limit of 9.1 mU/L. The system has successfully achieved on-chip detection of ALP with superior anti-interference capability and recoveries ranging from 96.8 % to 104.7 %, alongside relative standard deviations below 8.0 %. Significance and noveltyThe μDAD design accommodated both the photothermal reaction of PDA NPs and thermosensitive gas production reaction, achieving the rapid sensing of visual distance signals. The μDAD-based Cu2+-catalyzed photothermal sensing system holds substantial potential for applications in biochemical analysis and clinical diagnostics, underscored by the versatile Cu2+ regulation mechanism for a broad spectrum of biomarkers.

Mine waste rock as a soil amendment for enhanced weathering, ecosystem services, and bioenergy production

Enhanced weathering of terrestrial rock material is a promising method for the removal of anthropogenic CO2 emissions from the atmosphere. Herein, we demonstrate that an ameliorated mining waste product can be effectively weathered in the soil environment when used as a soil amendment in conjunction with the cultivation of fast-growing willows (Salix matsudana Koidz. ⨯ S. alba L. “Austree”) in a pot study environment. Utilizing this locally sourced amendment minimizes emissions associated with grinding and transportation of enhanced weathering materials. Results showed that the willows were able to tolerate the relatively high metal concentrations of this amendment and sequester inorganic carbon (C) through the production of bicarbonate in soil solution. During the period of peak plant growth (10 weeks after planting), alkalinity measurements of soil solution from pots with willows and the addition of 25% by mass mine waste product indicated an additional 10 mg of inorganic C sequestration per liter of leached soil solution compared to unamended soils with willows. This represents 4.5 times the inorganic C sequestration rate of unamended soils. The addition of ameliorated mining waste also increased the pH of the soil solution by up to two units (pH of 6 in control vs. pH of 8 with the addition of 25% by mass mineral amendment). In addition to inorganic C sequestration, weathering of the ameliorated mining waste product may also provide base cations (such as calcium and magnesium) which could improve soil fertility. These results are encouraging for future investigation of ameliorated mine waste rock to sequester carbon and enhance the production of willows grown for ecosystem services and phytotechnologies.

The Effects of a Novel Sodium Bicarbonate Ingestion System on Repeated 4 km Cycling Time Trial Performance in Well-Trained Male Cyclists

BackgroundA novel sodium bicarbonate (SB) product has come to market named the “Bicarb System” (M-SB; Maurten AB, Gothenburg, Sweden). It claims to minimise gastrointestinal (GI) discomfort whilst still improving exercise performance.AimTo investigate the effects of M-SB ingestion on repeated 4 km cycling time trials (TT1 and TT2) in well-trained male cyclists.MethodsThe study recruited ten well-trained cyclists (maximal oxygen uptake (V˙O2max\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{2\\max }$$\\end{document}): 67 ± 4 ml kg−1 min−1 BM; peak power output (PPO) at V˙O2max\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{2\\max }$$\\end{document}: 423 ± 21 W) to take part in this randomised, crossover and double-blinded study. Following one visit to determine V˙O2max\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{2\\max }$$\\end{document}, participants completed a second visit to identify individual time to peak blood bicarbonate (HCO3−) (ITTP) in a rested state. Visit three was a familiarisation trial mimicking the experimental procedures. Visits four to seven consisted of completing 2 × 4 km cycling TTs separated by 45 min passive recovery, following one of either: 0.3 g kg−1 BM M-SB, 0.21 g kg−1 BM sodium chloride (placebo; PLA) in vegetarian capsules (size 00), or a control trial (CON). Supplements (M-SB or placebo) were ingested pre-exercise at their respective ITTP.ResultsPerformance in TT1 was faster in the M-SB condition compared with TT1 in CON (− 5.1 s; p = 0.004) and PLA (− 3.5 s; p < 0.001). In TT2, performance was also significantly faster in the M-SB condition compared with CON (− 4.4 s; p = 0.018) or PLA (− 4.1 s; p = 0.002). Total aggregated GI symptoms were generally low and not significantly different between PLA and the M-SB conditions for a range of symptoms.ConclusionsThe ingestion of M-SB improves repeated 4 km cycling TT performance and the recovery of acid–base balance between bouts, whilst causing minimal GI discomfort.

Sustainable brine management: Unlocking magnesium and calcium for improved carbonation in the modified Solvay process

The extensive utilization of Reverse Osmosis (RO) in water desalination has led to the production of high-salinity brine, which poses significant environmental and societal challenges. This study presents an effective approach for the recovery of calcium and magnesium from real local RO brine. This method, serving as the initial step in a multi-treatment process, aims to efficiently manage brine and mitigate CO2 emission. Experimental outcomes demonstrate that a decarbonization pre-treatment, achieved through acidification, utilizes a near-stoichiometric ratio of sodium hydroxide to magnesium (2:1). This process, along with gradual addition of alkaline solution and adequate settling time, effectively removes more than 98 % of magnesium. Additionally, it precipitates high-purity magnesium hydroxide solids with large particles sizes (193.6 µm). In the subsequent soda ash stage, more than 97 % of calcium is successfully removed, yielding calcium carbonate with 95 % purity. Preliminary assessments of revenue generated from these products offer economic justifications for Zero Liquid Discharge implementation. Furthermore, Aspen Plus simulation for the carbonation process using the modified Solvay process revealed the significant benefits of the pretreatment process. This enhances sodium conversion efficiency, improves the production of sodium bicarbonate, and reduces impurities. These findings underscore the importance of Ca2+ and Mg2+ separation steps in improving the carbonation process.

Production of ammonium bicarbonate from the condensate of the upgrading biogas-pipelines

Developing a suite of biofuels for different applications relies heavily on upgrading technologies to remove nitrogen compounds and carbon dioxide. Particularly in the upgrading of biogas to biomethane, simple water scrubbing is the most widely used technology for biogas upgrading. This technology can be synergistically implemented without the need for additional equipment for processing steps, although this design has not been conceived yet. Samples of biogas-pipeline condensates were collected from 3 different anaerobic digestion plants processing 3 different feedstocks (i.e., food waste, agrowaste, and manure) at 3 different locations in each plant (i.e., biodigester and postdigester condensate pits, digestate pasteurizer, and biogas booster and chiller). The methodology for the analysis of the 5-mL biogas-pipeline condensates was acid-base titration with 0.06 M hydrochloric acid and 0.13 M sodium hydroxide solutions as titrants, and induction of crystallization by cooling at 3 °C, adding up to 40 mL of acetone as antisolvent, and settling for 12 h. The results showed that the concentration of ammonium bicarbonate in the condensates ranged from 0.75 to 50 g/L. The most suitable location to enhance the upgradation of biogas, formation of condensate, and precipitation of ammonium bicarbonate was the pit after the anaerobic digester and before the biogas storage. The most concentrated condensate was retrieved from the biogas-pipeline coming out of the pasteurization tank, but the operation at 70.5 °C also led to volatilization of organic compounds that negatively affected the biogas quality. Future work aims to investigate coating and granulation of ammonium bicarbonate crystals to improve their stability and commercialization.

An Evidence of Carbonic Anhydrase Activity in Native Microalgae for CO2 Capture Application.

A promising alternative for effective carbon capture has been found in microalgae because of their high photosynthetic capacity and quick growth. The carbon concentration mechanism of many microalgae is heavily reliant on the enzyme carbonic anhydrase (CA), which catalyze the production of bicarbonate from carbon dioxide. In this study, microalgal samples were collected, characterized, and cultured under controlled conditions for their optimal growth of cultures I-IX. The CA activity was investigated using a standard method; the Wilbur-Anderson assay was used to calculate CA activity in microalgal cultures. The comparative study was then used to measure the activity rate of the collected microalgae. Among the tested, culture I, VI, and IX showed a high enzyme activity rate of 4.15, 4.0, and 4.2µg·mL-1, respectively. To determine the rate of carbon dioxide hydration, the method involved tracking the pH change in a reaction mixture. In addition, genetic analysis facilitates the identification of key genes involved in CA activity and other metabolic processes, which enhance the knowledge of microalgal physiology, and enables genetic engineering efforts in the future studies. Overall, this investigation emphasizes the significance of studying unknown microalgal culture and their potential CA activity for industrial and bio-energy applications.

Development of a reference interval for urinary ammonia-to-creatinine ratio in feline patients.

Disruption of acid-base homeostasis can lead to many clinical problems. Ammonia excretion by the kidneys is critical to maintaining acid-base homeostasis through bicarbonate production. Measurement of ammonia excretion may help determine if the kidneys are properly functioning in maintaining acid-base balance. Reference intervals are essential tools for clinical decision-making but do not currently exist for urinary ammonia-to-creatinine ratio (UACR) in feline patients. This study aimed to generate a reference interval (RI) for UACR in healthy adult cats. The study used samples from client-owned adult healthy cats that presented to the University of Florida Primary Care and Dentistry service (n = 92). Physical examination, serum biochemistry, urinalysis, urine ammonia, and creatinine concentrations were measured. Cats were excluded if there were significant abnormalities in their urinalysis or biochemistry panel. The RI for UACR was calculated according to the recommendation of the American Society for Veterinary Clinical Pathology. The UACR was evaluated for correlation with serum bicarbonate, weight, age, and sex. The RI for UACR was 3.4-20.7 with 90% confidence intervals for the lower and upper limits of (3.0-3.7) and (16.0-23.7), respectively. No significant correlation with age, sex, or weight was found. There was no discernable relationship between serum bicarbonate and UACR. Establishing an RI for UACR in healthy adult cats will allow further studies to determine if changes in UACR are observed during specific disease states.

Ammonia Concentrator for Repeatable Adsorption/Desorption Using Nickel Hexacyanoferrate as Adsorbent and Production of Solid Ammonium Bicarbonate

Ammonia Concentrator for Repeatable Adsorption/Desorption Using Nickel Hexacyanoferrate as Adsorbent and Production of Solid Ammonium Bicarbonate

Functional activation of pyruvate dehydrogenase in human brain using hyperpolarized [1-13 C]pyruvate.

Pyruvate, produced from either glucose, glycogen, or lactate, is the dominant precursor of cerebral oxidative metabolism. Pyruvate dehydrogenase (PDH) flux is a direct measure of cerebral mitochondrial function and metabolism. Detection of [13 C]bicarbonate in the brain from hyperpolarized [1-13 C]pyruvate using carbon-13 (13 C) MRI provides a unique opportunity for assessing PDH flux in vivo. This study is to assess changes in cerebral PDH flux in response to visual stimuli using in vivo 13 C MRS with hyperpolarized [1-13 C]pyruvate. From seven sedentary adults in good general health, time-resolved [13 C]bicarbonate production was measured in the brain using 90° flip angles with minimal perturbation of its precursors, [1-13 C]pyruvate and [1-13 C]lactate, to test the hypothesis that the appearance of [13 C]bicarbonate signals in the brain reflects the metabolic changes associated with neuronal activation. With a separate group of healthy participants (n = 3), the likelihood of the bolus-injected [1-13 C]pyruvate being converted to [1-13 C]lactate prior to decarboxylation was investigated by measuring [13 C]bicarbonate production with and without [1-13 C]lactate saturation. In the course of visual stimulation, the measured [13 C]bicarbonate signal normalized to the total 13 C signal in the visual cortex increased by 17.1% ± 15.9% (p = 0.017), whereas no significant change was detected in [1-13 C]lactate. Proton BOLD fMRI confirmed the regional activation in the visual cortex with the stimuli. Lactate saturation decreased bicarbonate-to-pyruvate ratio by 44.4% ± 9.3% (p < 0.01). We demonstrated the utility of 13 C MRS with hyperpolarized [1-13 C]pyruvate for assessing the activation of cerebral PDH flux via the detection of [13 C]bicarbonate production.

Techno-economic assessment of the CO2 value chain with CCUS applied to a waste-to-energy Italian plant

Recently, post-combustion CO2 removal has been considered also for the CO2 separation from the flue gases of Waste-to-Energy (WtE) plants, that manage high amounts of Municipal Solid Waste (MSW) by combusting it and generating power and heat. Moreover, because of the presence in MSW of an organic waste fraction, net negative CO2 emissions are feasible when integrating CCUS systems into WtE plants. Currently, to the best of the authors’ knowledge, there are only few incineration plants around the world that are successfully coupled with a carbon capture system, resulting in near-zero (or even negative) CO2 emission power generation.This work focuses on the evaluation of the whole value chain of the non-biogenic CO2 that is emitted in a power plant located in Northern Italy and on its possible utilization, from the CO2 source in the flue gas to the market-ready product.The design of the process for the CO2 removal from the flue gas has been carried out specifically for the considered flue gas to be treated with an aqueous solution of MonoEthanolAmine 30% wt., the benchmark solvent used in other types of power plants (fuelled by coal and natural gas). The main process parameters (e.g., lean loading, absorber packing height, regenerator packing height, regenerator pressure, gas inlet temperature, solvent inlet temperature) have been selected in order to optimize the reboiler duty and the water requirement, the latter being usually not considered in literature works dealing with this type of analysis. Then, the CO2 utilization has been evaluated, considering the options of both sequestration in the Adriatic Sea and utilization of CO2 for production of sodium bicarbonate, on the basis of the information available in the literature.In compliance with Directive 2003/87/EC and with the Italian legislation, Waste-to-Energy plants that treat municipal solid waste are currently exempt from the application of the CO2 Emissions Trading System (ETS). This article speculates about the application of the ETS to an urban WtE plant, located in Northern Italy, and evaluates its economic implications by comparing the purchase of emission quotas with the construction of a CCS or CCU plant.A business plan, detailing the obtained revenues from the utilization and from the avoided cost of purchasing emission allowances and the expenses related to the operation of the carbon capture plant, taking into account the taxes and the inflation, has been created and used for comparing the two considered CO2 value chains. For the option of CO2 sequestration, sensitivity analyses on the variation of investment costs (+10 %), operating costs (+10 %) and revenues (−10 %) have been performed and the breakeven value of the ETS certificate that can make the Net Present Value (NPV) non-negative has been determined. For the option of CO2 utilization, the revenue from sodium bicarbonate that can make its production profitable has been evaluated.

Mechanism of a novel metal-free carbonic anhydrase.

The recently discovered metal-free carbonic anhydrase (CA) enzyme may significantly impact the global carbon dioxide (CO2) cycle, as it can irreversibly perform the CO2 hydration reaction. In this study, we investigated several key aspects of metal-free CA, including the identification of the catalytic site, the determination of the CO2 binding site, and the mechanism of catalysis. This is achieved through classical molecular dynamics (MD) simulations, quantum chemical density functional theory (DFT), and hybrid quantum mechanics/molecular mechanics (QM/MM) calculations. Our study indicates that the experimental structure based on X-ray crystallography, which shows the 'bicarbonate (HCO3-) product' trapped in the hydrophilic region of metal-free CA, might not accurately depict the actual enzyme-substrate interaction. Instead, the simulation reveals that CO2 prefers the hydrophobic zone, which serves as the primary catalytic site. It also highlights the strategic role of a gatekeeper residue (Phe504), which assists in regulating the transportation of CO2 by tilting its aromatic plane. Additionally, the hybrid QM/MM calculations establish that CO2 hydration is catalyzed within the hydrophobic zone by a deprotonated tyrosine with the help of an organized water chain.

Unraveling the Potential of Electrochemical pH-Swing Processes for Carbon Dioxide Capture and Utilization.

Global warming, driven by the accumulation of anthropogenic greenhouse gases, particularly CO2, in the atmosphere, has garnered significant attention due to its detrimental environmental impacts. To combat this critical issue, the deployment of CO2 capture and utilization (CCU) strategies has been considered as one of the technology-based solutions, leading to extensive scientific and engineering research. Electrochemical pH-swing (EPS) processes offer a promising approach to diverse CCU pathways, such as the delivery of pure CO2 gas, the delivery of bicarbonate (e.g., for microalgae cultivation), and the formation of carbonate minerals. In this study, we discuss several CCU pathways using EPS and provide an in-depth analysis of its mechanisms and potential applications, outlining its limitations from both thermodynamic and kinetic standpoints. The EPS process has demonstrated remarkable capabilities, achieving a CO2 capture efficiency of over 90% and unlocking valuable opportunities for CCU applications. We also develop an initial techno-economic assessment and provide the perspectives and challenges for future development and deployment of EPS. This study sheds light on the integration of EPS with CCU, closing the carbon cycle by effectively utilizing the products generated through the process, such as carbonate minerals and bicarbonate solution. For instance, the bicarbonate product can serve as a viable feedstock for bicarbonate-based microalgae production systems, with the added benefit of reducing costs by 40-80% compared to traditional gaseous CO2 delivery approaches. By integration of electrochemical technologies with CCU methods, this study underscores the immense potential for mitigating CO2 emissions and advancing sustainable practices to combat global warming. This study not only addresses the urgent need for effective solutions but also paves the way for a greener and more sustainable future.

Longitudinal assessment of mitochondrial dysfunction in acute traumatic brain injury using hyperpolarized [1-13 C]pyruvate.

[13 C]Bicarbonate formation from hyperpolarized [1-13 C]pyruvate via pyruvate dehydrogenase, a key regulatory enzyme, represents the cerebral oxidation of pyruvate and the integrity of mitochondrial function. The present study is to characterize the chronology of cerebral mitochondrial metabolism during secondary injury associated with acute traumatic brain injury (TBI) by longitudinally monitoring [13 C]bicarbonate production from hyperpolarized [1-13 C]pyruvate in rodents. Male Wistar rats were randomly assigned to undergo a controlled-cortical impact (CCI, n = 31) or sham surgery (n = 22). Seventeen of the CCI and 9 of the sham rats longitudinally underwent a 1 H/13 C-integrated MR protocol that includes a bolus injection of hyperpolarized [1-13 C]pyruvate at 0 (2 h), 1, 2, 5, and 10 days post-surgery. Separate CCI and sham rats were used for histological validation and enzyme assays. In addition to elevated lactate, we observed significantly reduced bicarbonate production in the injured site. Unlike the immediate appearance of hyperintensity on T2 -weighted MRI, the contrast of bicarbonate signals between the injured region and the contralateral brain peaked at 24 h post-injury, then fully recovered to the normal level at day 10. A subset of TBI rats demonstrated markedly increased bicarbonate in normal-appearing contralateral brain regions post-injury. This study demonstrates that aberrant mitochondrial metabolism occurring in acute TBI can be monitored by detecting [13 C]bicarbonate production from hyperpolarized [1-13 C]pyruvate, suggesting that [13 C]bicarbonate is a sensitive in-vivo biomarker of the secondary injury processes.

Production of high-purity carbon dioxide and sodium bicarbonate by lime cellar gas cleaning and chemical recycling: Process simulation and techno-economic analysis

The cement industry is responsible for 8% of total global CO2 emissions, which mainly originate from limestone calcination and fuel combustion. In view of the application potential of using CO2 to produce chemicals, this paper developed a novel process based on the Aspen Plus process simulation for the co-production of 99.99% CO2 by means of Methyldiethanolamine (MDEA) absorption/desorption and NaHCO3 by carbonization of CO2, NH3 and Na2SO4. The effects of absorption temperature, NH3 and Na2SO4 feeding amount, crystallizer temperature and pressure on CO2 capture rate and utilization rate were explored. The results showed that the best CO2 capture rate was achieved when the cellar gas inlet temperature of the absorber tower was 37 °C; Saturated Na2SO4 solution was favorable for CO2 absorption, and the CO2 utilization rate increased with the increase of Na2SO4 dosage; NaHCO3 yield decreased with the increase of crystallizing temperature, and the best NaHCO3 yield was achieved when the crystallizer temperature was 35.5 °C; Crystallizing pressure had little impact on the reaction. Economic analysis showed that the project will start to be profitable in 6.48 years with a Net Return Rate (NRR) value of 13.51%. It indicates that the project has economic benefits and provides a new way to reduce CO2 emissions from lime cellar gas.

Investigating Cardiac Metabolism in the Isolated Perfused Mouse Heart with Hyperpolarized [1-13C]Pyruvate and 13C/31P NMR Spectroscopy.

Metabolism is the basis of important processes in cellular life. Characterizing how metabolic networks function in living tissues provides crucial information for understanding the mechanism of diseases and designing treatments. In this work, we describe procedures and methodologies for studying in-cell metabolic activity in a retrogradely perfused mouse heart in real-time. The heart was isolated in situ,in conjunction with cardiac arrest to minimize the myocardial ischemia and was perfused inside a nuclear magnetic resonance (NMR) spectrometer. While in the spectrometer and under continuous perfusion, hyperpolarized [1-13C]pyruvate was administered to the heart, and the subsequent hyperpolarized [1-13C]lactate and [13C]bicarbonate production rates served to determine, in real-time, the rates of lactate dehydrogenase and pyruvate dehydrogenase production. This metabolic activity of hyperpolarized [1-13C]pyruvate was quantified with NMR spectroscopy in a model free-manner using the product selective saturating-excitations acquisition approach. 31P spectroscopy was applied in between the hyperpolarized acquisitions to monitor the cardiac energetics and pH. This system is uniquely useful for studying metabolic activity in the healthy and diseased mouse heart.

The pathophysiology of distal renal tubular acidosis

The kidneys have a central role in the control of acid-base homeostasis owing to bicarbonate reabsorption and production of ammonia and ammonium in the proximal tubule and active acid secretion along the collecting duct. Impaired acid excretion by the collecting duct system causes distal renal tubular acidosis (dRTA), which is characterized by the failure to acidify urine below pH 5.5. This defect originates from reduced function of acid-secretory type A intercalated cells. Inherited forms of dRTA are caused by variants in SLC4A1, ATP6V1B1, ATP6V0A4, FOXI1, WDR72 and probably in other genes that are yet to be discovered. Inheritance of dRTA follows autosomal-dominant and -recessive patterns. Acquired forms of dRTA are caused by various types of autoimmune diseases or adverse effects of some drugs. Incomplete dRTA is frequently found in patients with and without kidney stone disease. These patients fail to appropriately acidify their urine when challenged, suggesting that incomplete dRTA may represent an intermediate state in the spectrum of the ability to excrete acids. Unrecognized or insufficiently treated dRTA can cause rickets and failure to thrive in children, osteomalacia in adults, nephrolithiasis and nephrocalcinosis. Electrolyte disorders are also often present and poorly controlled dRTA can increase the risk of developing chronic kidney disease.

A Combined Approach for the Treatment of Textile Dye Bath Effluent Using CO2 Gas

In this study, baking soda extraction from textile dye bath effluent has been investigated. The novel notion of employing amino acid additions to improve the standard Solvay method and thereby boost the efficiency of Na+ recovery has been investigated. Glycine, L-arginine, and L-alanine are three amino acid additions examined for their effect on enhancing Na+ recovery, and the best-suited additive is chosen. The dumping of brackish dye bath effluent, which has a high percentage of sodium chloride, causes textile dye baths from the textile industry. The primary goal was to remove Na+ (sodium) from the effluent using carbon dioxide gas, which has environmental benefits. Carbon dioxide (CO2) is the most common greenhouse gas, trapping heat and raising global temperatures, therefore contributing to climate change. The Solvay process is used to transform Na+ in salty wastewater into a valuable product. The effect of different operating variables such as NH4OH (ammonium hydroxide) concentration, reaction temperature, carbonation time, and carbon dioxide gas flow rate on bicarbonate production was investigated. Maximum sodium recovery of about 68 percent is attained under optimal circumstances. When compared with the regular Solvay process, the modified Solvay method has a greater recovery efficiency (33 percent). Amino acid addition (arginine) improved conversion efficiency while also lowering the process’s ammonia need.

Production of Sodium Bicarbonate with Saline Brine and CO2 Co-Utilization: Comparing Modified Solvay Approaches

The present work investigates the production of sodium bicarbonate in combination with the co-utilization of saline brine and carbon capture, utilization, and sequestration (CCUS). The use of ammonia in the traditional Solvay process could be eliminated by using a modified Solvay process. This study compared the modification with the addition of three buffering additives: Ca(OH)2, KOH, and NH4HCO3. The effectiveness of these processes, using two qualities of saline brine (desalination and aquifer), is compared based on the purity of the produced NaHCO3. It was found that the use of Ca(OH)2 did not produce high-purity NaHCO3, while NH4HCO3 and KOH performed better. Desalination brine utilization with NH4HCO3 resulted in the production of high-purity NaHCO3, while the second most suitable method involved the use of KOH, and the main co-product formed was Na2CO3. Geochemical modeling is performed in order to have insights into the carbonation (in the reactor) and precipitation (in the oven) behavior of the reactions. It predicted the precipitation of mineral phases well, though kinetics might hinder some saturated solids to dissolve first. The present study shows that accurate characterization is critical to accurately assess the success of modified Solvay processes. The use of QXRD and SEM analyses, complemented with geochemical modeling, helped to better understand the processes and the formation of NaHCO3. Further investigations on diverse brines could provide for their better utilization by the geological carbon sequestration and water desalination industries that produce them.

Real-Time Pyruvate Chemical Conversion Monitoring Enabled by PHIP.

In recent years, parahydrogen-induced polarization side arm hydrogenation (PHIP-SAH) has been applied to hyperpolarize [1-13C]pyruvate and map its metabolic conversion to [1-13C]lactate in cancer cells. Developing on our recent MINERVA pulse sequence protocol, in which we have achieved 27% [1-13C]pyruvate carbon polarization, we demonstrate the hyperpolarization of [1,2-13C]pyruvate (∼7% polarization on each 13C spin) via PHIP-SAH. By altering a single parameter in the pulse sequence, MINERVA enables the signal enhancement of C1 and/or C2 in [1,2-13C]pyruvate with the opposite phase, which allows for the simultaneous monitoring of different chemical reactions with enhanced spectral contrast or for the same reaction via different carbon sites. We first demonstrate the ability to monitor the same enzymatic pyruvate to lactate conversion at 7T in an aqueous solution, in vitro, and in-cell (HeLa cells) via different carbon sites. In a second set of experiments, we use the C1 and C2 carbon positions as spectral probes for simultaneous chemical reactions: the production of acetate, carbon dioxide, bicarbonate, and carbonate by reacting [1,2-13C]pyruvate with H2O2 at a high temperature (55 °C). Importantly, we detect and characterize the intermediate 2-hydroperoxy-2-hydroxypropanoate in real time and at high temperature.

Antiulcerogenic and healing activity of hecogenin acetate in rodents.

Peptic ulcers are lesions in the gastric and duodenal mucosa generated by an imbalance between protective factors (gastroduodenal mucus secretion, bicarbonate production, adequate blood flow) and harmful factors (excess pepsin or hydrochloric acid). Some drugs used in peptic ulcer therapy are associated with adverse effects. The aim of this study was to evaluate the antiulcerogenic and healing activity of hecogenin acetate (HA) in acute and chronic models of gastric lesions in rodents. The antiulcerogenic activity of HA was evaluated in models of gastric lesions induced by absolute ethanol and in acidified ethanol with HA (5, 10, and 20mg/kg). For the model of gastric lesions induced by ischemia and reperfusion, rats were pre-treated with HA (5, 10, 20mg/kg). After that, they were submitted to 30min of ischemia, followed by 1h of reperfusion. To evaluate the healing activity was induced gastric ulcer using acetic acid (80%) in rats. After 24h, they were treated for 7 consecutive days with HA (10 and 20mg/kg). They were evaluated the possible signs of toxicity, measurement of the lesions, collagen deposition, and histological analysis. HA significantly reduced the area of the lesion in models of gastric lesions induced by absolute and acidified ethanol, ischemia-induced gastric lesions and reperfusion, and regarding healing. In the collagen deposition, the presence and increase of collagen demonstrate the healing effect. The AH has antiulcerogenic and healing potential demonstrated by the decrease in gastric injury and presence of collagen fibers, respectively.