Process modelling for industrial scale polyhydroxybutyrate production using fructose, formic acid and CO2: Assessing carbon sources and economic viability.

Polyhydroxybutyrate (PHB) is a biodegradable polymer that has potential to replace petroleum-derived plastics. However, the commercialisation of PHB is hindered by high production costs. In this study, the material flow and economics of an industrial scale PHB production process using fructose, formic acid and carbon dioxide (CO2) as carbon sources were simulated and analysed. The lowest breakeven price of 3.64 $/kg PHB was obtained when fructose was utilized as carbon source. When formic acid and CO2 were used, the breakeven price was 10.30 and 10.24 $/kg PHB due to raw material cost, respectively. Although using formic acid and CO2 is more expensive, they meet the emerging sustainable needs for plastic production and contribute to the circular economy via CO2 fixation. This study suggests that the use of formic acid and CO2 as feedstock for PHB production has potential to become competitive in the bioplastic market with further research.

A Prospective Life Cycle Assessment of Electrochemical CO2 Reduction to Selective Formic Acid and Ethylene.

Invited for this month's cover is the group of Prof. Dr. Wee-Jun Ong at Xiamen University Malaysia. The image shows a model of Xiamen University and is in celebration of the 5th and 100th anniversary of Xiamen University Malaysia and Xiamen University, respectively. The cover showcases the institutes as a pillar of renewable nanotechnology research and a key player in the ever-growing search for sustainable energy. The Research Article itself is available at 10.1002/cssc.202200857.

Lithium salts: assessment of their chronic and acute toxicities to honey bees and their anti-Varroa field efficacy.

BACKGROUND: Varroa control is essential for the maintenance of healthy honey bee colonies. Overuse of acaricides has led to the evolution of resistance to those substances. Studies of the short-term acaricidal effects and safety of various lithium (Li) salts recently have been reported. This study examined the long-term in vitro and in vivo bee toxicities, short-term motor toxicity to bees and long-term anti-Varroa field efficacy of several Li salts. RESULTS: In an in vitro chronic-toxicity assay, lithium citrate (18.8 mm) was the most toxic of the examined salts, followed by lithium lactate (29.5 mm), and lithium formate (32.5 mm). In terms of acute locomotor toxicity to bees, all of the Li salts were well-tolerated and none of the treatment groups differed from the negative control group. In an in vitro survival study, all of the Li treatments significantly reduced bee life spans by a factor of 1.8-7.2, as compared to the control. In terms of life expectancy, lithium citrate was the most toxic salt, with no significant differences noted between lithium formate and lithium lactate. In the bee-mortality field study, none of the examined treatments differed from the negative control. Amitraz and lithium formate exhibited similar acaricide effects, which were significantly different from those observed for lithium lactate and the negative control. CONCLUSION: In light of lithium formate's honey bee safety and efficacy as an acaricide, additional sublethal toxicity studies in brood, drones and queens, as well as tests aimed at the optimization of administration frequency are warranted. © 2022 Society of Chemical Industry.

A Prospective Life Cycle Assessment of Electrochemical CO2 Reduction to Selective Formic Acid and Ethylene.

Converting CO2 into valuable C1 -C2 chemicals through electrochemical CO2 reduction (ECR) has potential to remedy the ever-increasing climate problems owing to the intensification of industrial activity. In this work, cradle-to-gate life cycle assessment (LCA) was performed to quantify the environmental impacts of formic acid (FA) and ethylene production through ECR benchmarked with the conventional processes. At the midpoint level, global warming potential (GWP) effects of FA and ethylene production through ECR recorded 5.6 and 1.6-times that of the conventional process, respectively. Although ECR currently has limited environmental benefits, the incorporation of hydropower has vast potential after evaluating four sustainable electricity sources, namely hydropower, wind, solar, and biomass. Notably, ECR to FA recorded a 24 % reduction in petrochemical usage. For ethylene production, human health damage, ecosystem damage, and petrochemical use were reduced by 67, 94, and 110 %, respectively. Sensitivity analysis indicated that a sustainable energy supply chain for ECR will accelerate the development of a circular economy.

RIFM fragrance ingredient safety assessment, 3-phenylpropyl acetate, CAS Registry Number 122-72-5.

Therefore, the phenethyl formate MOE for the fertility endpoint can be calculated by dividing the phenethyl alcohol NOAEL in mg/kg/day by the total systemic exposure to phenethyl formate, 1000/0.00062 or 1612903.

RIFM fragrance ingredient safety assessment, cis-3-hexenyl methyl carbonate, CAS Registry Number 67633-96-9.

The following paper presents the method of determination of the percolation threshold in cement composites with expanded graphite by impedance spectroscopy. Most of the applications of cement composites with conductive additives require exceeding the percolation threshold. The ionic conductivity of cement matrix below the percolation threshold has a major impact on the conductivity of the composite, as a result, it significantly hinders the exploitation of these composites. The electric properties of cement composites with expanded graphite were evaluated by DC measurements and impedance spectroscopy (IS). Based on Nyquist plots, two equivalent circuits were adopted for the composites. Next, the values of capacitance and inductance of cement composites with expanded graphite were calculated from the fitted equivalent circuits. The analysis of the results shows that the percolation threshold occurs when the reactance of the composite changes from captative to inductive. Comparison between the values of percolation threshold obtained from DC measurements and IS shows that the method is effective for cement composites with conductive additives.

Photochemical degradation of fragrance ingredient benzyl formate in water: Mechanism and toxicity assessment.

Recently, fragrance ingredients have attracted increasing attention due to their imperceptible risks accompanying the comfortable feeling. To understand transformation mechanisms and toxicity evolution of benzyl formate (BF) in environment, its photochemical degradation in water was thoroughly studied herein. Results showed that 83.5% BF was degraded under ultraviolet (UV) irradiation for 30 min. Laser flash photolysis and quenching experiments demonstrated that triplet excited state (3BF*), O2•-, and 1O2 were three main reactive species found during BF photodegradation. Eight degradation intermediates, including benzaldehyde, benzyl alcohol, o-cresol, bibenzyl, benzyl ether, 1,2-diphenylethanol, benzoic acid, and benzylhemiformal, were mainly formed as identified by LC-Q-TOF/MS and GC-MS analyses. Furthermore, the degradation mechanism was explained as the bond cleavage of 3BF* and BF•+, O2•-/1O2 oxidation, eaq- reduction, and •OH addition reactions. Aquatic assessment suggests that except benzyl alcohol, benzoic acid, and benzylhemiformal, all the products were persistent and could result in increased aquatic toxicity compared to original BF. Consequently, these degradation products may cause more toxicity to organisms if they remain accumulated in water environment for a long time.

An Ion-exchange Bone Demineralization Method for Improved Time, Expense, and Tissue Preservation.

Here, we describe an ethylenediaminetetraacetic acid (EDTA)-based bone demineralization procedure that uses cation-exchange resin and dialysis tubing. This method does not require solution changes or special equipment, is faster than EDTA alone, is cost-effective, and is environmentally friendly. Like other EDTA-based methods, this procedure yields superior tissue preservation than formic acid demineralization. Greater protein antigenicity using EDTA as opposed to formic acid has been described, but we also find significant improvements in carbohydrate-based histological staining. Histological staining using this method reveals cartilage layers that are not distinguishable with formic acid demineralization. Carbohydrate preservation is relevant to many applications of bone demineralization, including the assessment of osteoarthritis from bone biopsies and the use of demineralized bone powder for tissue culture and surgical implants. The improvements in time, expense, and tissue quality indicate this method is a practical and often superior alternative to formic acid demineralization.