Empirical Buswell’s equation for biomethane formation is a bioredox and bioenergy model for identifying the elemental composition, redox properties, and thermal properties of anaerobic digestate. The anaerobic digestion metrics for evaluating the degradability performance of organic matter such as biodegradability index, electron conversion efficiency, and energy conversion efficiency have already been developed. In this research, the theoretical and experimental heat of bioredox in anaerobic digestion are quantified, in which calculations are demonstrated by step-by-step procedures. Then the relationships between the established heat of bioredox conversion efficiency in anaerobic digestion and pre-existing anaerobic digestion metrics are bridged. The research finds out that: (i) both theoretical and experimental heat of anaerobic digestion are equal to zero, (ii) both theoretical and experimental heat of bioredox in anaerobic digestion are less than zero, (iii) heat of bioredox conversion efficiency in anaerobic digestion is identical to its biodegradability index and electron conversion efficiency, (iv) when higher heating value of organic matter is counted by the modified Dulong formula, heat of bioredox conversion efficiency in anaerobic digestion is not equal to energy conversion efficiency, (v) when higher heating value of organic matter is counted by the theoretical higher heating formula, heat of bioredox conversion efficiency in anaerobic digestion is equal to energy conversion efficiency, and (vi) empirical Buswell’s equation can be used as a device to validate the experimental biomethane potential of organic matter and empirical formula of anaerobic digestate.
Empirical Buswell’s equation for biohydrogen is a stoichiometric model to identify elemental composition and thermal properties of dark fermentation effluent. Biodegradability index, energy conversion efficiency, and electron conversion efficiency are applied to evaluate the degradability performance of organic matter. Based on empirical Buswell’s equation for biohydrogen, experimental heat of dark fermentation is determined by mass percentages of elements of organic matter and experimental biohydrogen yield. In this study, the calculation of theoretical and experimental heat of dark fermentation for dark fermentation effluent are demonstrated by step-by-step procedures. The macroscopic energy-based metric, heat conversion efficiency, is established and defined as the ratio of experimental heat of dark fermentation to theoretical heat of dark fermentation. The study concludes that: (i) both theoretical and experimental heat of dark fermentation are endothermic reactions, (ii) theoretical higher heating value and standard heat of formation of dark fermentation effluent in kilojoule per gram is greater than those of organic matter, (iii) heat conversion efficiency is identical to biodegradability index, (iv) heat conversion efficiency is less than energy conversion efficiency, and (v) heat conversion efficiency and electron conversion efficiency are identical.
Combustion and dark fermentation are two important types of redox reactions. The former uses molecular oxygen as the oxidizing agent and the latter uses proton as the oxidizing agent. Dark fermentation is represented by Buswell’s equation for biohydrogen, which is composed of two sub-reactions: bioredox and biohydrolysis. Unlike heat of combustion, heat of dark fermentation is a concept that is rarely explored. In this research, with the help of Hess’s law, reactions of organic combustion and molecular hydrogen combustion are converted to Buswell’s equation for biohydrogen. The corresponding thermochemical equation for dark fermentation can then be identified accordingly. Based on a given chemical formula in the form of either empirical formula or structural formula, the relationship between standard heat of dark fermentation, standard heat of bioredox, and standard heat of biohydrolysis is established. Using the derived mathematical equations, standard heat of dark fermentation, standard heat of bioredox, and standard heat of biohydrolysis are determined.
Long-standing debates, along with the implementation and certification process of CBAM, have ushered in a new era of trade policy closely linked to the carbon content of traded goods. The application of tariffs based on the carbon content of traded products is expected to raise awareness of the ongoing debates about the environmental aspects of trade and how trade relations will develop in the future. The EU's environmental targets and the way environmental standards are applied to trade have been the subject of much debate. In particular, the selection of the five sectors with the highest carbon emissions has had far greater implications for trade relations than simply applying CBAM to emission-intensive sectors. The goal of reducing emissions from the agricultural sector is not a new topic being discussed today; various guidelines exist on the future of agriculture and the implementation of policies, interventions, and incentives aimed at reducing emissions from human-induced activities associated with agricultural production. The implementation of CBAM and the development of technologies related to reducing carbon emissions have brought about new debates, shifting the focus from the policies enabling CBAM implementation to technological advancements.
Background: Anaerobic digestion is a microbial-mediated biochemical reaction. Buswell’s equation representing anaerobic digestion is used to understand the degradability performance of organic matter and energy conversion. Thermodynamic parameters govern energy efficiency, temperature sensitivity, and process stability. While Buswell’s equation predicts stoichiometry, there is lack of study on the integration of enthalpy change, entropy change, and Gibbs free energy change across diverse organic matter. Method: Enthalpy change of anaerobic digestion is calculated by using parameters of organic matter, mathematical framework of Buswell’s model, and thermochemical equation. Furthermore, thermodynamic equations are applied to quantify and understand the nature of standard enthalpy change, standard entropy change, and standard Gibbs free energy change of anaerobic digestion. Results: Using methane as a standard reference, a set of 21 organic matter (CxHyOzClwNvSuPt) is selected. (i) Through the experimental heat of formation and stoichiometric coefficient of Buswell’s equation, the standard enthalpy change is found in the range of −303.19 kJ/mol (sucrose) and +186.42 kJ/mol (naphthalene). (ii) All the calculated standard entropy change are between +110.63 J/K (formic acid) and +2289.60 J/K (triphenyl phosphate), therefore anaerobic digestion is an entropy-dominated reaction. (iii) The calculated standard Gibbs free energy change is in the range of −885.32 kJ/mol (sucrose) and −57.74 kJ/mol (acetic acid), therefore anaerobic digestion is a spontaneous reaction. (iv) As temperature increases, the product of temperature times entropy change becomes more positive, and Gibbs free energy change to become more spontaneous. Significance: Based on the collected data of standard heat of formation and standard absolute entropy, or standard Gibbs free energy formation of any chemical formula of organic matter, a unified thermodynamic framework of Buswell’s equation is established. Thermodynamic parameters of organic matter for anaerobic digestion can be quantified.
This paper investigates the occurrence of rare earth elements (REEs) in coal fly ash (CFA) as a potential alternative source of critical minerals, which are essential for clean energy applications and advanced chemical technologies. In this study, bulk CFA samples from Lingan and Point Aconi power stations in Nova Scotia were characterized to assess the presence of highly critical rare earth element oxides (HCREEOs) and REE-bearing mineral phases. X‑ray diffraction (XRD) analyses were conducted on both bulk materials and fine fractions (<45μm). Moisture content, particle size distribution, and carbon content were additionally measured to support resource assessment and extend prior research that focused primarily on environmental implications of CFA. Both CFA samples exhibited low moisture and carbon contents, although the Lingan sample contained comparatively higher carbon content than the Point Aconi sample. Particle-size analysis revealed that the Lingan CFA is dominated by fine and ultrafine particles, whereas the Point Aconi CFA is enriched in intermediate fractions, with both materials largely demonstrating particle sizes within the 75–150μm range. The identification of REE-bearing phases in these samples indicates the potential for further evaluation of CFA as a viable feedstock for REE recovery. These findings support further investigation into the technical and economic feasibility of commercial extraction of critical REEs from coal fly ash resources from Nova Scotia.
Organic combustion and anaerobic digestion are two important types of redox reactions. The former uses molecular oxygen as oxidizing agent and organic carbon as reducing agent. The latter uses organic carbons as both oxidizing agent and reducing agent. Anaerobic digestion is represented by Buswell’s equation. It is composed of series of bioredox and biohydrolysis reactions. To count heat of anaerobic digestion, structural formula and heat of formation of organic matter are required. To overcome these restrictions, this research establishes a simple equation for determining heat of anaerobic digestion. Hess’s Law is used to convert organic combustion equations to Buswell’s equation. Then, the corresponding thermochemical equation for standard heat of anaerobic digestion is deduced. This research concludes that: (i) ideal standard heat of anaerobic digestion is equal to zero, (ii) heat of bioredox is dependent on Buswell’s electron, (iii) standard heat of biohydrolysis is equal to the negative value of standard heat of bioredox, and (iv) standard Gibbs free energy change is equal to the negative product of temperature times standard entropy change.
International Journal of Chemistry wishes to acknowledge the following individuals for their assistance with peer review of manuscripts for this issue. Their help and contributions in maintaining the quality of the journal is greatly appreciated. Many authors, regardless of whether International Journal of Chemistry publishes their work, appreciate the helpful feedback provided by the reviewers. Reviewers for Volume 18, Number 1 Ahmet Ozan Gezerman, Toros Agri-Industry, Research and Development Center, Turkey Daniel Rivera-Vazquez, Northwestern State University of Louisiana, USA Ho Soon Min, INTI International University, Malaysia Kevin C. Cannon, Penn State Abington, USA Khaldun Mohammad Al Azzam, The University of Jordan, Jordan Nanthaphong Khamthong, Rangsit University, Thailand Nejib Hussein Mekni, Al Manar University, Tunisia Sitaram Acharya, Dallas College, USA Tony Di Feo, Natural Resources Canada, Canada Albert John On behalf of, The Editorial Board of International Journal of Chemistry Canadian Center of Science and Education
Over the past decade a number of 1,4-naphthoquinones, most commonly occurring quinones have been isolated from natural sources and synthesized. Naturally occurring naphthoquinone derivatives, such as juglone methyl ether, plumbagin, droserone, and lawsone, possess significant medicinal properties and have been synthesized by several synthetic pathways.
Curcumin analogue compounds derived from benzaldehyde moieties originating from p-dimethylaminebenzaldehyde namely (1E,4E)-1,5-bis[4-(dimethylamino)phenyl]penta-1,4-dien-3-one (A1) and (3E,5E)-1-benzyl-3,5-bis[[4-(dimethylamino)phenyl]methylidene]piperidin-4-one (A2), were synthesized through a base-catalyzed condensation using a sonication method. The reaction proceeded to afford a yellow crystalline product in 74.31% and 91.02% yield. The synthesized compounds were fully characterized using ATR-IR, ¹H-NMR, and ¹³C-NMR. In addition, in silico studies were performed to evaluate the binding affinity of the curcumin analogues against key cancer-related proteins, including EGFR, Bcl-2, and p53 mutant, using AutoDock Vina. Docking results revealed that the analogues (A1 and A2) exhibited higher binding affinity toward EGFR and mutant p53 compared to curcumin and the native ligands. For Bcl-2, the analogues displayed a binding affinity higher than curcumin but lower than the native ligand. The in vitro cytotoxicity of the synthesized compounds was evaluated using the MTT assay on T47D breast cancer cells and normal Vero cells. The curcumin analogues (A1 and A2) demonstrated very strong cytotoxic activity with an IC₅₀ of 10.09 μg/mL and 7.66 μg/mL while curcumin exhibited an IC₅₀ of 4.010 μg/mL. Both compounds showed high selectivity toward cancer cells over normal cells. These findings indicate that the synthesized curcumin analogue possesses promising anticancer potential supported by both computational and biological evaluations.
Buswell’s equation for biohydrogen is a stoichiometric model for representing dark fermentation. With this equation, the biodegradability performance and energy change of organic matter can be well understood. In this research, thermodynamics is used to assess energy properties and temperature sensitivity of organic matter in dark fermentation. The unified thermodynamic framework is applied to quantify standard enthalpy change, standard entropy change, standard Gibbs free energy change of dark fermentation, and to establish the relationship between the energy change of organic matter and the spontaneity of dark fermentation. This research concludes: (1) dark fermentation is an endothermic reaction, (2) dark fermentation is an entropy-dominated reaction, (3) only limited numbers of organic matter such as carbohydrates, formic acid, and chloroform are spontaneous in dark fermentation at standard state, (4) temperature increase transforms non-spontaneous organic matter into spontaneous organic matter for biohydrogen formation, and (5) positive Gibbs free energy change and high spontaneous temperature of organic matter are the thermodynamic constraints for low biohydrogen yield in dark fermentation.
A new series of different heterocyclic derivatives was prepared via a facile unimolecular condensation of D-iso ascorbic acid with o-chlorophenyl hydrazine to give D-erythro-2,3-hexodiulosono-1,4-lactone 2-( o-chlorophenyl hydrazine (2). Reactions of (2) with hydroxylamine gave the 2-( o-chlorophenyl hydrazone)-3-oxime (3). On boiling with boiling acetyl chloride, (3) gave 2-o-chlorophenyl-4-(2,3-di-O-acetyl-D-erythro-glyceryl-1-yl)-1,2,3-triazole-5-carboxylic acid-5,1́-lactone (4). In the treatment of (3) with benzoyl chloride in pyridine the same dehydrative cyclization occurred giving, 2-o-chlorophenyl-4-(2,3-di-o-benzoyloxy-D-erythro-glycerol-1-yl)-1,2,3-triazole-5-carboxylic acid-5,1΄-lactone (5). On the treatment of compound (4) with liquid ammonia in methanol, deacetylation occurred concurrently with the opening of the lactone ring, to afford the 2-o-chlorophenyl-4-(D-erythro-glycerol-1-yl)-1,2,3-triazole-5-carboxamide (6). Similarly, treatment of compound (4) with hydrazine hydrate in methanol, afforded 2-o-chlorophenyl-4-(D-erythro-glycerol-1-yl)-1,2,3-triazole-5-carboxylic acid hydrazide (7). The controlled reaction of (3) with sodium hydroxide, followed by neutralization, gave 3-(D-erythro-glycerol-1-yl)-4,5-isoxazoline-5-(4H)-one-4-o-chlorophenyl hydrazone (8). Reaction of (3) with HBr-AcOH gave 5-O-acetyl-6-bromo-6-deoxy-D-erythro-2,3-hexodiulosono-1,4-lactone-2-(o-chlorophenyl hydrazone)-3-oxime (9); these were converted into 4-(2-O-acetyl-3-bromo-3-deoxy-l-threo-glycerol-l-yl)-2-aryl-1,2,3-triazole-5-carboxylic acid 5,41-lactones on treatment with acetic anhydride-pyridine. Compound (3) treatment with bromine-water caused its cyclization and bromination of the phenyl group to give carboxylic acid 5,1΄-lactone (10). Acetylation of (10) gave the diacetate (11), which upon treatment with hydrazine hydrate in methanol, afforded compound (12), mild acetylation of compound (12) gave the triacetate (13) boiling of (13) with acetic anhydride afforded hexa acetyl derivative (14). on the treatment of compound (11) with liquid ammonia in methanol deacetylation occurred to afford 1,2,3-triazole-5-carboxamide derivative (15). On the other hand, treatment of compound (3) with bromine-water for a short time yielded 3-oxime (16). Subsequent acetylation with boiling acetic anhydride afforded compound (11). In addition, acetylation of compound 3 afforded a diacetyl derivative assigned as 5,6-di-O-acetyl-D-erythro-2,3-hexodilusono-1,4-lactone-(2-o-chlorophenyl hydrazone)-3-acetoxime (17), which on boiling with acetic anhydride cyclization occurred giving compound (4). On the treatment of Dehydro-L-ascorbic acid-2-phenyl hydrazone (L-threo-2,3-hexodiulosono- 1,4-lactone 2-phenylhydrazone (19) with acetic anhydride/pyridine, afforded 5,6-di-O-acetyl-3-acetoxime (20) that upon treatment with boiling acetic anhydride, afforded the triazole derivative (21). Furthermore, treatment of the monophenyl hydrazone (18) with S-benzyl hydrazine carbodithiolate in the presence of acetic acid, afforded the bis-hydrazone, L-threo-2,3-hexodilusono-1,4-lactone-3-(S-benzylhydrazinocarbodithiolate)-2-phenylhydrazone (22). Acetylation of compound (22) with acetic anhydride and pyridine did not give the di-O-acetyl derivative expected but instead, elimination of a molecule of acetic acid and partial hydrolysis of a hydrazone residue took place to give compound (23). The structures of all the synthesized compounds were confirmed using elemental analysis and different spectral tools. Eight samples from the synthesized compounds, 2,3, 4,10.16,11,12,17 were tested for their antimicrobial activity and they showed no activities.
be represented by Buswell’s equation. When the chemical formula of organic matter is identified, the mean oxidation number of organic carbons, theoretical amount of biomethane, theoretical biomethane potential, and theoretical number of transferred electrons can be determined. Currently, the biodegradability performance of organic matters in anaerobic digestion is measured by two metrics: the biodegradability index and the energy conversion efficiency. However, the concept of electron conversion efficiency has not been rigorously studied. This article serves two purposes: to develop a new electron-based metric, and to investigate the relationships between this metric and the two preexisting biodegradability performance metrics. Having calculated these said metrics through a series of procedures using mass percentages of elements and experimental biomethane potential as key parameters, this research concludes that the microscopic electron conversion efficiency and the macroscopic mass-based biodegradability index are numerically identical, and the electron conversion efficiency and energy conversion efficiency display a strong linear correlation.
Cement and steel production, it released a large number of CO2 (about 4.5-5 billion tons/year), serious air pollution. The making use of Carbon Gasification Reaction-CGR (CO2 + C = 2 CO - 162.4 kj/mol) to convert the CO2 into gas CO, can get 4.581- 5.09 trillion M3 CO gas, It is equivalent to 1,6 to 1,8 Billion M3 energy of natural gas, which is equivalent to the annual transportation capacity of about 30 Nord Stream No2 lines. Abundant reserves of limestone and iron ore have become raw materials for fuel production. The Water Gas Reaction-WGR ( C+H2O=H2+CO - 118.82kj/mol) can be utilized to produce gas using green energy sources such as firewood, plastics, and rubber etc.,Due to its abundant resources, low cost and significant reduction in CO2 emissions, the author believes that this reaction can save the Earth and humanity.
It has been pointed out that so-called plasma labile iron (or NTBI = non-transferrin-bound iron) is the essential cause of many cancers and Alzheimer’s disease, but its actual properties have not been clarified. Nishida have concluded that the structure of highly toxic plasma labile iron is an oxo-bridged diiron species through the experimental results using many artificial iron chelating agents. Based on this result, he synthesized non-toxic chelating agents (SP9 and SP10) that prevent the formation of the oxo-bridged di-iron species, and found that these chelates effectively suppress the proliferation of various types of cancers, proving the correctness of his conclusion. He also obtained many related results which support that SP9 and SP10 can be applied to prevent Alzheimer’s disease. Furthermore, Nishida have demonstrated that some zinc ions can remove these dangerous oxo-bridged diiron species through the formation of iron deposition. Nishida have shown that his universal healthcare, so-called “Labile Iron Controllng Therapy” (LICT), which prevents cancers and Alzheimer’s disease through suppressing the formation of dangerous oxo-bridged di-iron species in the human body, can be achieved through daily diet that contain suitable zinc ions and natural lignin derivatives.
Anaerobic digestion is a sustainable process that occurs under anaerobic microorganism-mediated conditions. In this process, organic matters generate biogas and digestate in the gas-aqueous solution-solid multiphases system. Molecular Buswell’s equation has been widely applied for neutral organic matter. In contrast, ionic Buswell’s equation has been given little attention. This article uses the proton method to develop a stoichiometric ionic Buswell’s equation for neutral and ionic organic matters. When an empirical formula of organic matter is given, its stoichiometric ionic Buswell’s equation can be balanced and deduced. Conversely, when a structural formula is given, it must go through either the fragmentation method to identify the designated products or the carbon-atom method to identify the organic fragmented formula. The designated products or the organic fragmented formula can then be input into the proton method to balance the ionic Buswell’s equation. Based on any given organic matter, regardless of its electrical charge and nature of formula, the mean oxidation number of organic carbons, parameters of organic matter, parameters of Buswell’s equation, and ionic Buswell’s equation can be determined. Compared to molecular Buswell’s equation, the established ionic Buswell’s equation is an extended model for understanding physical, chemical, and biochemical processes among water molecules, ionic species, and neutral species in the multiphases anaerobic digestion system.
Dark fermentation is an anaerobic microbial-mediated redox system represented by Buswell’s equation for biohydrogen, in which thermal parameters such as theoretical higher heating value and energy conversion efficiency are applied to evaluate the degradability performance of organic matter, but the standard heat of Buswell’s equation for biohydrogen has not been established. Likewise, the standard heat of biohydrolysis and standard heat of bioredox, two sub-reactions of dark fermentation, have not yet been established. This study uses the stoichiometric Buswell’s equation for biohydrogen as an energy model to quantify the standard heat of Buswell’s equation for biohydrogen, the standard heat of biohydrolysis, and the standard heat of bioredox. Through the integration of the theoretical higher heating value of organic matter and mathematical thermal mathematical equation of Buswell’s equation for biohydrogen, this study concludes that (i) the standard heat of Buswell’s equation for biohydrogen is demonstrated as an endothermic reaction, (ii) the standard heat of Buswell’s equation for biohydrogen is identified as the sum of the standard heat of biohydrolysis and the standard heat of bioredox, (iii) the standard heat of bioredox can be calculated using the theoretical higher heating value of organic matter via the derived mathematical equation, and (iv) the standard heat of biohydrolysis can be determined by the difference between the standard heat of Buswell’s equation for biohydrogen and the standard heat of bioredox.
Heat of formation is a critical parameter which represents the stability of matter and helps the understanding of the nature of chemical conversions. Biomass is a renewable energy material, however, there is very limited study on heat of formation of biomass. This situation inhibits study on the thermal nature of biomolecules and the counting of heat of bioconversions. The goal of this research is to formulate a simple mathematical equation for counting heat of formation of biomass. The research is divided into three sections: (i) determination of theoretical higher heating value by an empirical formula of biomass, (ii) identification of the relationship between atomic coefficients of empirical formula and stoichiometric coefficients of organic combustion, and (iii) counting of heat of formation of biomass in a thermochemical organic combustion equation. The research concludes that for any given empirical formula of biomass, the corresponding standard heat of formation can be determined by the established mathematical thermochemical organic combustion equation.
Organic combustion is a classic redox reaction. In the study of stoichiometric organic combustion, structural formula has been given little attention when compared to empirical formula. This article uses the arithmetic method to develop a chemical formula-based molecular organic combustion equation, in which the mean oxidation number of organic carbons is selected to be a redox and structural metric for differentiating empirical formula and structural formula, connecting redox parameters, and balancing organic combustion equations. When any empirical formula of organic matter is given, the organic combustion equation can be balanced and deduced. Furthermore, when known atomic coefficients of an empirical formula are input into the general deduced organic combustion equation, the balanced organic combustion can be easily determined. Comparatively, when any structural formula is given, it must undergo the fragmentation method to have the designated products identified and then the arithmetic method can be applied to balance the organic combustion equation. More importantly, this study establishes that for any given chemical formula of organic matter, the parameters of organic matter, the redox parameters of organic combustion, and the balanced organic combustion equation can be determined.
This paper explores the potential of green catalysis as a sustainable solution to industrial pollution. By examining the core principles of green chemistry and the development of eco-friendly catalytic systems, it evaluates how green catalysis can reduce hazardous waste, lower energy consumption, and improve emission control in chemical manufacturing. The study highlights advancements such as nanocatalysts, enzyme engineering, and photocatalysis, illustrating their role in minimizing environmental harm while maintaining industrial productivity. For example, enzyme-based biocatalysts have shown promise in pharmaceutical applications due to their high selectivity and mild operating conditions. The research also addresses key challenges including process scalability, cost-efficiency, and catalyst stability across different industries. Future directions are proposed to support broader implementation, including investment in green technologies and regulatory incentives. The findings underscore the vital importance of green catalysis in advancing cleaner manufacturing practices and aligning chemical production with global sustainability goals. The study concludes that widespread adoption of green catalysts could transform the environmental impact of modern industry.
