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Distillation serves as the foremost method for commercial-scale separation of fluid mixtures. Widely applied in wastewater treatment, it is the preferred choice for isolating volatile multi-component mixtures into pure substances. Distillation technology offers notable economic benefits due to its easy implementation, high efficiency, productivity, and robust safety features. This study examines the environmental impacts associated with the production and usage of a distillation, specifically in treating pharmaceutical process wastewater containing organic halogen compounds (AOX). The analysis adopts a 'gate-to-gate' approach, with the specified functional unit (FU) set at 1 kg of treated effluent containing no more than 8 ppm of AOX and less than 1000 mg O2/L of Chemical Oxygen Demand (COD). In this work, Life Cycle Assessment (LCA) is conducted using Product Environmental Footprint (PEF) and Recipe 2016 Endpoint (H) V1.06 methodologies, utilizing the SimaPro V9.3.0.3 software in conjunction with the Ecoinvent V3.8 database. Analysis results have shown the emission of 1.11 × 10 –2  kg CO 2 -eq, in which operational and production processes contribute 91.9% and 8.1%, respectively. To mitigate adverse effects, alternative energy sources, i.e., solar, offshore wind, and onshore wind are integrated into the distillation procedure. The substitution of hard coal with solar, offshore wind, and onshore wind energy displays the potential to significantly reduce climate change impact by 64.3%, 62.9%, and 62.8%, respectively. Article Highlights Distillation process undergoes a thorough life cycle assessment from production to application. Distillation process requires high energy and emits 1.11 × 10 –2  kg CO 2 -eq per functional unit. The operational phase dominates over 90% in three damage categories: human health, ecosystems, and resources.

We investigated dioxin formation and removal in a commercial thermal waste treatment plant employing a gasification and melting process that has become widespread in the last decade in Japan. The aim was to clarify the possibility of dioxin formation in a process operation at high temperatures and the applicability of catalytic decomposition of dioxins. Also, the possible use of dioxin surrogate compounds for plant monitoring was further evaluated. The main test parameter was the influence of changes in the amount and type of municipal solid waste (MSW) supplied to the thermal waste treatment plant which from day to day operation is a relevant parameter also from commercial perspective. Here especially, the plastic content on dioxin release was assessed. The following conclusions were reached: (1) disturbance of combustion by adding plastic waste above the capability of the system resulted in a considerable increase in dioxin content of the flue gas at the inlet of the bag house and (2) bag filter equipment incorporating a catalytic filter effectively reduced the gaseous dioxin content below the standard of 0.1 ng toxic equivalency (TEQ)/m 3 N , by decomposition and partly adsorption, as was revealed by total dioxin mass balance and an increased levels in the fly ash. Also, the possible use of organohalogen compounds as dioxin surrogate compounds for plant monitoring was further evaluated. The levels of these surrogates did not exceed values corresponding to 0.1 ng TEQ/m 3 N dioxins established from former tests. This further substantiated that surrogate measurement therefore can well reflect dioxin levels.

Hypervalent Iodine Chemistry is the first comprehensive text covering all of the main aspects of the chemistry of organic and inorganic polyvalent iodine compounds, including applications in chemical research, medicine, and industry. Providing a comprehensive overview of the preparation, properties, and synthetic applications of this important class of reagents, the text is presented in the following way:  The introductory chapter provides a historical background and describes the general classification of iodine compounds, nomenclature, hypervalent bonding, structural features, and the principles of reactivity of polyvalent iodine compounds. Chapter 2 gives a detailed description of the preparative methods and structural features of all known classes of organic and inorganic derivatives of polyvalent iodine. Chapter 3, the key chapter of the book, deals with the many applications of hypervalent iodine reagents in organic synthesis. Chapter 4 describes the most recent achievements in hypervalent iodine catalysis. Chapter 5 deals with recyclable polymer-supported and nonpolymeric hypervalent iodine reagents. Chapter 6 covers the \"green\" reactions of hypervalent iodine reagents under solvent-free conditions or in aqueous solutions. The final chapter provides an overview of the important practical applications of polyvalent iodine compounds in medicine and industry. This book is aimed at all chemists interested in iodine compounds, including academic and industrial researchers in inorganic, organic, physical, medicinal, and biological chemistry. It will be particularly useful to synthetic organic and inorganic chemists, including graduate and advanced undergraduate students. It comprehensively covers the green chemistry aspects of hypervalent iodine chemistry, making it especially useful for industrial chemists.

Fluoropolymers are used in many technologically demanding applications because of their balance of high-performance properties. A significant impediment to the synthesis of variants of commercially available amorphous fluoropolymers is their general insolubility in most solvents except chlorofluorocarbons (CFCs). The environmental concerns about CFCs can be circumvented by preparing these technologically important materials in supercritical fluids. The homogeneous solution polymerization of highly fluorinated acrylic monomers can be achieved in supercritical carbon dioxide by using free radical methods. In addition, detailed decomposition rates and efficiency factors were measured for azobisisobutyronitrile in supercritical carbon dioxide and were compared to those obtained with conventional liquid solvents.

Halogen compounds have been studied widely due to their unique hypercoordinated and hypervalent features. Generally, in halogen compounds, the maximal coordination number of halogens is smaller than eight. Here, based on the particle swarm optimization method and first-principles calculations, we report an exotically icosahedral cage-like hypercoordinated IN 6 compound composed of N 6 rings and an unusual iodine−nitrogen covalent bond network. To the best of our knowledge, this is the first halogen compound showing twelve-fold coordination of halogen. High pressure and the presence of N 6 rings reduce the energy level of the 5d orbitals of iodine, making them part of the valence orbital. Highly symmetrical covalent bonding networks contribute to the formation of twelve-fold iodine hypercoordination. Moreover, our theoretical analysis suggests that a halogen element with a lower atomic number has a weaker propensity for valence expansion in halogen nitrides. High pressure can modify the chemical properties of the elements, giving rise to exotic bonding. Here the authors report the prediction of a nitrogen-rich iodine nitride compound IN 6 where the iodine atom has an unusual twelve-fold coordination, stable above 100 GPa.

The atmospheric lifetimes of the fluorinated gases CF$_4$, C$_2$F$_6$, c-C$_4$F$_8$, (CF$_3$)$_2$c-C$_4$F$_6$, C$_5$F$_12$, C$_6$F$_14$, C$_2$F$_5$Cl, C$_2$F$_4$Cl$_2$, CF$_3$Cl, and SF$_6$ are of concern because of the effects that these long-lived compounds acting as greenhouse gases can have on global climate. The possible atmospheric loss processes of these gases were assessed by determining the rate coefficients for the reactions of these gases with O($^1$D), H, and OH and the absorption cross sections at 121.6 nanometers in the laboratory and using these data as input to a two-dimensional atmospheric model. The lifetimes of all the studied perfluoro compounds are >2000 years, and those of CF$_3$Cl, CF$_3$CF$_2$Cl, and CF$_2$CICF$_2$Cl are >300 years. If released into the atmosphere, these molecules will accumulate and their effects will persist for centuries or millennia.

* Byproduct formation mechanisms during electrochemical oxidation water treatment. * Control byproduct formation by quenchers. * Process optimization to suppress byproduct formation. Electrochemical oxidation (EO) is a promising technique for decentralized wastewater treatment, owing to its modular design, high efficiency, and ease of automation and transportation. The catalytic destruction of recalcitrant, non-biodegradable pollutants (per- and poly-fluoroalkyl substances (PFAS), pharmaceuticals, and personal care products (PPCPs), pesticides, etc.) is an appropriate niche for EO. EO can be more effective than homogeneous advanced oxidation processes for the degradation of recalcitrant chemicals inert to radical-mediated oxidation, because the potential of the anode can be made much higher than that of hydroxyl radicals (E OH = 2.7 V vs. NHE), forcing the direct transfer of electrons from pollutants to electrodes. Unfortunately, at such high anodic potential, chloride ions, which are ubiquitous in natural water systems, will be readily oxidized to chlorine and perchlorate. Perchlorate is a to-be-regulated byproduct, and chlorine can react with matrix organics to produce organic halogen compounds. In the past ten years, novel electrode materials and processes have been developed. However, spotlights were rarely focused on the control of byproduct formation during EO processes in a real-world context. When we use EO techniques to eliminate target contaminants with concentrations at μg/L-levels, byproducts at mg/L-levels might be produced. Is it a good trade-off? Is it possible to inhibit byproduct formation without compromising the performance of EO? In this mini-review, we will summarize the recent advances and provide perspectives to address the above questions.

Oxidation of bromide in aqueous environments initiates the formation of molecular halogen compounds, which is important for the global tropospheric ozone budget. In the aqueous bulk, oxidation of bromide by ozone involves a [Br•OOO − ] complex as intermediate. Here we report liquid jet X-ray photoelectron spectroscopy measurements that provide direct experimental evidence for the ozonide and establish its propensity for the solution-vapour interface. Theoretical calculations support these findings, showing that water stabilizes the ozonide and lowers the energy of the transition state at neutral pH. Kinetic experiments confirm the dominance of the heterogeneous oxidation route established by this precursor at low, atmospherically relevant ozone concentrations. Taken together, our results provide a strong case of different reaction kinetics and mechanisms of reactions occurring at the aqueous phase-vapour interface compared with the bulk aqueous phase. Heterogeneous oxidation of bromide in atmospheric aqueous environments has long been suspected to be accelerated at the interface between aqueous solution and air. Here, the authors provide spectroscopic, kinetic and theoretical evidence for a rate limiting, surface active ozonide formed at the interface.

Bromoform (CHBr3) contributes to stratospheric ozone depletion but is not regulated under the Montreal Protocol due to its short lifetime and large natural sources. Here, we show that anthropogenic sources contribute significantly to the amount of CHBr3 transported into the Northern Hemisphere (NH) extratropical stratosphere. We present a new CHBr3 emission inventory comprised of natural and anthropogenic sources, with the latter estimated from ship ballast, power plant cooling and desalination plant brine water. Including anthropogenic sources in the new inventory increases CHBr3 emissions by up to 31.5% globally and 70.5% in the NH. In consequence, atmospheric CHBr3 is also significantly higher, especially over the NH extratropics during boreal winter. Here anthropogenic sources enhance bromine at the tropopause by 0.9 ppt Br, thus doubling natural CHBr3 abundances. For some latitudes, tropopause bromine increases by 2.4 ppt Br suggesting significant contributions of anthropogenic CHBr3 to the NH lowermost stratosphere. Plain Language Summary Halogen‐containing compounds are emitted at the Earth's surface and transported into the stratosphere, where they contribute to the depletion of the ozone layer. Emissions of long‐lived halogen compounds such as CFC‐11 have been reduced following the implementation of the Montreal Protocol and its later adjustments. Emissions of short‐lived halogen‐containing compounds, on the other hand, are currently not regulated. Within this group, bromoform (CHBr3) is one of the most abundant compounds and has been known to have mostly natural sources. In this study, we present a new data set of CHBr3 emissions which includes anthropogenic sources from industrial water use. We show that these anthropogenic sources increase global CHBr3 emissions by one‐third. Our results also suggest that the anthropogenic emissions contribute significantly to the amount of CHBr3 transported into the stratosphere over the Northern Hemisphere mid‐latitudes. Key Points A new CHBr3 emission inventory based on natural and anthropogenic sources suggests that the latter account for 12%–28% of the global emissions In the NH, new anthropogenic estimates increase known natural CHBr3 emissions by up to 70.5%, leading to higher atmospheric CHBr3 levels At the NH extratropical tropopause, CHBr3 is enhanced by 0.9 ppt Br due to anthropogenic sources thus doubling natural CHBr3 abundances

Few studies have investigated the impact of new particle formation (NPF) on cloud condensation nuclei (CCN) in remote Antarctica, and none has elucidated the relationship between NPF and CCN production. To address that knowledge gap, we continuously measured the number size distribution of 2.5–300 nm particles and CCN number concentrations at King Sejong Station on the Antarctic Peninsula from 1 January to 31 December 2018. Ninety-seven NPF events were detected throughout the year. Clear annual and seasonal patterns of NPF were observed: high concentration and frequency of nucleation-mode particles in summer (December–February: 53 NPF cases) and undetected nucleation-mode particles in winter (June–August: no NPF cases). We estimated the spatial scale of NPF by multiplying the time during which a distinct nucleation mode can be observed at the sampling site by the locally measured wind speed. The estimated median spatial scale of NPF around the Antarctic Peninsula was found to be approximately 155 km, indicating the large scale of NPF events. Air back-trajectory analysis revealed that 80 cases of NPF events were associated with air masses originating over the ocean, followed by sea-ice (12 cases), multiple (3 cases), and land (2 cases) regions. We present and discuss three major NPF categories: (1) marine NPF, (2) sea-ice NPF, and (3) multiple NPF. Satellite estimates for sea-surface dimethylsulfoniopropionate (DMSP; a precursor of gaseous dimethyl sulfide) data showed that the production of oceanic biogenic precursors could be a key component in marine NPF events, whereas halogen compounds released from ice-covered areas could contribute to sea-ice NPF events. Terrestrial sources (wildlife colonies, vegetation, and meltwater ponds) from Antarctica could affect aerosol production in multiple air masses. Out of 97 observed NPF events, 83 cases were characterized by the simultaneous increase in the CCN concentration by 2 %–270 % (median 44 %) in the following 1 to 36 h (median 8 h) after NPF events. Overall, Antarctic NPF events were found to be a significant source of particles with different physical characteristics and related to biogenic sources in and around the Antarctic Peninsula, which subsequently grew to cloud condensation nuclei.