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Plastic waste has emerged as a serious issue due to its impact on environmental degradation and resource scarcity. Plastic recycling, especially of halogen-containing plastics, presents challenges due to potential secondary pollution and lower-value implementations. Chemical recycling via pyrolysis is the most versatile and robust approach for combating plastic waste. In this Review, we present recent advancements in halogen-plastic pyrolysis for resource utilization and the potential pathways from “reducing to recycling to upcycling” halogens. We emphasize the advanced management of halogen-plastics through copyrolysis with solid wastes (waste polymers, biomass, coal, etc.), which is an efficient method for dealing with mixed wastes to obtain high-value products while reducing undesirable substances. Innovations in catalyst design and reaction configurations for catalytic pyrolysis are comprehensively evaluated. In particular, a tandem catalysis system is a promising route for halogen removal and selective conversion of targeted products. Furthermore, we propose novel insights regarding the utilization and upcycling of halogens from halogen-plastics. This includes the preparation of halogen-based sorbents for elemental mercury removal, the halogenation–vaporization process for metal recovery, and the development of halogen-doped functional materials for new materials and energy applications. The reutilization of halogens facilitates the upcycling of halogen-plastics, but many efforts are needed for mutually beneficial outcomes. Overall, future investigations in the development of copyrolysis and catalyst-driven technologies for upcycling halogen-plastics are highlighted.

The introduction of biodegradable plastics is considered a practical approach to reducing plastic waste accumulation in the environment. Regardless of their biodegradability, plastics should be recycled to effectively utilize and circulate carbon as a resource. Herein, the use of pyrolysis was examined as a method for recycling two common biobased/biodegradable plastics: PLA and PHBH. The pyrolysis of PLA produced lactides (10.7 wt% at 400 °C), but the yield was decreased when the pyrolysis temperature was increased. The presence of steam promoted the hydrolysis of PLA: a steam concentration of 25 vol % increased, the production of lactides at 400 °C to 17.4 wt%. The pyrolysis of PHBH primarily yielded crotonic acid (30.1 wt% at 400 °C), and the yield increased with increasing pyrolysis temperature (71.8 wt% at 800 °C). Steam injection increased the hydrolysis of oligomers, resulting in a 76.1 wt% yield of crotonic acid at 600 °C with a steam concentration of 25 vol %. Thus, we determined that hydrolysis and pyrolysis progress simultaneously under a steam atmosphere, increasing the chemical feedstock recovery from PLA and PHBH. These findings may lead to the proposal of effective degradation methods for treating biobased/biodegradable plastic wastes and ways to maximize the conversion efficiency and target product yields.

Accumulating evidence indicates that aberrant signalling stemming from genetic abnormalities in cancer cells has a fundamental role in their evasion of antitumour immunity. Immune escape mechanisms include enhanced expression of immunosuppressive molecules, such as immune-checkpoint proteins, and the accumulation of immunosuppressive cells, including regulatory T (Treg) cells, in the tumour microenvironment. Therefore, Tregcells are key targets for cancer immunotherapy. Given that therapies targeting molecules predominantly expressed by Tregcells, such as CD25 or GITR, have thus far had limited antitumour efficacy, elucidating how certain characteristics of cancer, particularly genetic abnormalities, influence Tregcells is necessary to develop novel immunotherapeutic strategies. Hence, Tregcell-targeted strategies based on the particular characteristics of cancer in each patient, such as the combination of immune-checkpoint inhibitors with molecularly targeted agents that disrupt the immunosuppressive networks mediating Tregcell recruitment and/or activation, could become a new paradigm of cancer therapy. In this Review, we discuss new insights on the mechanisms by which cancers generate immunosuppressive networks that attenuate antitumour immunity and how these networks confer resistance to cancer immunotherapy, with a focus on Tregcells. These insights lead us to propose the concept of ‘immuno-genomic precision medicine’ based on specific characteristics of cancer, especially genetic profiles, that correlate with particular mechanisms of tumour immune escape and might, therefore, inform the optimal choice of immunotherapy for individual patients.

Lung cancer is one of the most aggressive tumour types. Targeted therapies stratified by oncogenic drivers have substantially improved therapeutic outcomes in patients with non-small-cell lung cancer (NSCLC)1. However, such oncogenic drivers are not found in 25–40% of cases of lung adenocarcinoma, the most common histological subtype of NSCLC2. Here we identify a novel fusion transcript of CLIP1and LTKusing whole-transcriptome sequencing in a multi-institutional genome screening platform (LC-SCRUM-Asia, UMIN000036871). The CLIP1–LTKfusion was present in 0.4% of NSCLCs and was mutually exclusive with other known oncogenic drivers. We show that kinase activity of the CLIP1–LTK fusion protein is constitutively activated and has transformation potential. Treatment of Ba/F3 cells expressing CLIP1–LTK with lorlatinib, an ALK inhibitor, inhibited CLIP1–LTK kinase activity, suppressed proliferation and induced apoptosis. One patient with NSCLC harbouring the CLIP1–LTKfusion showed a good clinical response to lorlatinib treatment. To our knowledge, this is the first description of LTKalterations with oncogenic activity in cancers. These results identify the CLIP1–LTKfusion as a target in NSCLC that could be treated with lorlatinib.

The entire world is moving toward carbon neutrality, and Japan is aiming to achieve a carbon neutral society by 2050. Generation of waste plastic is annually increasing, and the demand for waste plastic recycling is rapidly and globally growing to allow sustainable plastic use. Therefore, rapid and substantial promotion of plastic recycling technology is a global preferential task. The authors believe that pyrolysis is a promising strategy for recovering chemical feedstock from waste plastics, which improves global recycling capacity. Herein, global trends in waste plastic recycling were summarized in the first chapter, and feedstock recycling through pyrolysis-based approaches for hard-to-recycle plastic wastes such as polyethylene terephthalate (PET) and polyurethanes (PUs) were reviewed in the second chapter. Finally, the applicability of pyrolysis-gas chromatography (Py-GC) was verified by the investigation of the pyrolysis reaction mechanism, in situpyrolyzate monitoring, and rapid screening of pyrolysis and catalytic reaction conditions.This account article summarized global trends in waste plastic recycling, feedstock recycling through pyrolysis-based approaches for hard-to-recycle plastic wastes, and the applicability of pyrolysis-gas chromatography (Py-GC) for investigating the pyrolysis reaction mechanism, in situ pyrolyzate monitoring, and rapid screening of pyrolysis and catalytic reaction conditions.

Aberrant signalling of ERBB family members plays an important role in tumorigenesis and in the escape from antitumour immunity in multiple malignancies. Molecular-targeted agents against these signalling pathways exhibit robust clinical efficacy, but patients inevitably experience acquired resistance to these molecular-targeted therapies. Although cancer immunotherapies, including immune checkpoint inhibitors (ICIs), have shown durable antitumour response in a subset of the treated patients in multiple cancer types, clinical efficacy is limited in cancers harbouring activating gene alterations of ERBB family members. In particular, ICI treatment of patients with non-small cell lung cancers with epidermal growth factor receptor (EGFR) alterations and breast cancers with HER2alterations failed to show clinical benefits, suggesting that EGFR and HER2 signalling may have an essential role in inhibiting antitumour immune responses. Here, we discuss the mechanisms by which the signalling of ERBB family members affects not only autonomous cancer hallmarks, such as uncontrolled cell proliferation, but also antitumour immune responses in the tumour microenvironment and the potential application of immune-genome precision medicine into immunotherapy and molecular-targeted therapy focusing on the signalling of ERBB family members.

Mg-Al layered double hydroxide intercalated with CO32−(CO3·Mg-Al LDH) is effective for treating HCl exhaust gas. HCl reacts with CO32−in CO3·Mg-Al LDH, resulting in the formation of Cl·Mg-Al LDH. We propose that CO2can be used for the desorption of Cl−from Cl·Mg-Al LDH to regenerate CO3·Mg-Al LDH. Herein, we studied the desorption of Cl−from Cl·Mg-Al LDH by adding water to Cl·Mg-Al LDH and blowing CO2into it. We also analyzed the effects of temperature and water addition speed on the desorption of Cl−from Cl·Mg-Al LDH. Our results show that the added water adhered to Cl·Mg-Al LDH and that CO2in the gaseous phase was dissolved in this adhered water, thus generating CO32−. Therefore, anion exchange occurred between CO32−and Cl−in the Cl·Mg-Al LDH, thus desorbing Cl−.

Pyrolysis is considered to be a promising method for polymer characterization (in the field of analytical pyrolysis) and for chemical feedstock recovery from plastic wastes (in the field of applied pyrolysis) because it can decompose any polymeric material into smaller molecules by applying heat alone in an inert atmosphere. Pyrolysis–gas chromatography (Py-GC) involves pyrolyzing polymeric materials in a micropyrolyzer and a subsequent direct GC analysis of pyrolyzates. Py-GC has immense potential for applications in the fields of both analytical and applied pyrolysis, as it allows for rapid and accurate analysis of pyrolyzates. This is beneficial for elucidating microstructure and composition of polymers and for a rapid screening of pyrolysis conditions for designing feedstock recycling processes. In this review, we examined the latest research trends in Py-GC applications for polymer characterization, analysis of plastics in the environment, and chemical feedstock recovery from plastics.

In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g−1for urea, 18 mg·g−1for creatinine, and 20 mg·g−1for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500 °C, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process.

Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) is a promising technique allowing the rapid characterization of the polymer structure and additives of microgram-scale plastics. However, the Py-GC/MS analysis of polymers with urethane bonds is challenging because they produce highly reactive pyrolyzates such as amines and isocyanates polymerizing in the GC column, which limits the efforts to elucidate the pyrolysis mechanism and plastic characterization by online GC analysis. Herein, a novel pyrolysis-gas-phase derivatization-GC/MS (Py-GPD-GC/MS) technique was developed, allowing the pyrolysis of polymers and the subsequent direct gas-phase derivatization of pyrolyzates, employing a modified tandem μ-reactor-GC/MS system. This work conducted the gas-phase trifluoroacetylation of 4,4′-methylenedianiline (MDA), which is one of the major polyurethane (PU) pyrolyzates, using N-methyl-bis-trifluoroacetamide (MBTFA) as a derivatization agent. The trifluoroacetylation gas-phase reaction was monitored by in situGC/MS analysis and the effects of derivatization conditions were investigated. The highest MDA conversion observed was 65.6 area %. Furthermore, the sequential PU pyrolysis and direct trifluoroacetylation of PU pyrolyzates in the first μ-reactor and second μ-reactor, respectively, were successfully operated, achieving the inhibited polymerization and detection of trifluoroacetylated derivatives. Thus, the Py-GPD-GC/MS method has a significant potential to be applied for other combinations of pyrolyzates and derivatization reactions, enabling deeper characterization of plastics producing highly reactive pyrolyzates that cannot be accurately analyzed by conventional Py-GC/MS analysis.

The dechlorination (de-Cl) process for polyvinyl chloride wastes not only removes chlorine (Cl) that is undesired in the subsequent thermal treatment but also potentially establishes a Cl cycle that avoids NaCl production. Because the de-Cl process utilizes a mixture of sodium hydroxide (NaOH) and ethylene glycol (EG), the recovery of both Cl ions and EG is practically necessary for economic and environmental reasons. Designing an electrodialysis (ED) process that can recover Cl ions and EG from their mixture requires an understanding of the expected trade-off among the extent of recovery, energy consumption, and other unforeseen factors prior to the experiments. Here, the trade-off is assessed by combining laboratory-scale experiments, simulation for scale-up, and ex-ante life cycle assessment (LCA). Laboratory-scale ED experiments were performed by varying NaCl concentration in EG, NaCl concentration in water, and electrode voltage. In experiments, a Cl yield over 90% was achieved with an electrode voltage at 2.5 V, and treatment was still possible when the NaCl/H2O solution was concentrated to saturation. Based on the experiments, a commercial-scale ED process was simulated to provide LCA with inventory data under different ED operation conditions. The results revealed high environmental impacts caused by the solvent penetration reported in our previous study. To reduce the environmental impacts, a high NaCl concentration in EG is preferable, while the membranes and the electrode voltage need to be optimized to balance Cl recovery efficiency and environmental impacts, which are suggested for the future direction of research and development.

Immune checkpoint blockade has provided a paradigm shift in cancer therapy, but the success of this approach is very variable; therefore, biomarkers predictive of clinical efficacy are urgently required. Here, we show that the frequency of PD-1+CD8+T cells relative to that of PD-1+regulatory T (Treg) cells in the tumor microenvironment can predict the clinical efficacy of programmed cell death protein 1 (PD-1) blockade therapies and is superior to other predictors, including PD ligand 1 (PD-L1) expression or tumor mutational burden. PD-1 expression by CD8+T cells and Tregcells negatively impacts effector and immunosuppressive functions, respectively. PD-1 blockade induces both recovery of dysfunctional PD-1+CD8+T cells and enhanced PD-1+Tregcell–mediated immunosuppression. A profound reactivation of effector PD-1+CD8+T cells rather than PD-1+Tregcells by PD-1 blockade is necessary for tumor regression. These findings provide a promising predictive biomarker for PD-1 blockade therapies.

A low carbon yield is a major limitation for the use of cellulose-based filaments as carbon fiber precursors. The present study aims to investigate the use of an abundant biopolymer chitosan as a natural charring agent particularly on enhancing the carbon yield of the cellulose-derived carbon fiber. The ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH]OAc) was used for direct dissolution of cellulose and chitosan and to spin cellulose–chitosan composite fibers through a dry-jet wet spinning process (Ioncell). The homogenous distribution and tight packing of cellulose and chitosan revealed by X-ray scattering experiments enable a synergistic interaction between the two polymers during the pyrolysis reaction, resulting in a substantial increase of the carbon yield and preservation of mechanical properties of cellulose fiber compared to other cobiopolymers such as lignin and xylan.

Ni/Mg/Al catalysts with different atomic ratios were synthesized and tested for simultaneous H2-rich syngas recovery and toxic hydrogen cyanide (HCN) removal from polyurethane cushion waste. The waste decomposition products were converted into H2-rich syngas, and toxic HCN was removed using the Ni/Mg/Al catalysts. The catalyst composition drastically affected the ease of reduction to metallic Ni. Easily reduced catalysts effectively increased the syngas yield with red-Ni1.0Mg2.1Al6.0, giving the maximum syngas yield (1925 mL/g sample). Moreover, smaller Ni particle sizes (high dispersion) resulted in more effective HCN decomposition. Thus, red-Ni1.0Mg4.9Al4.1gave the lowest HCN yield (0.9 wt %) and concentration (0.5 vol %). Durability testing revealed a decrease in the catalytic activity with repeated use (first cycle, 1497 mL/g sample; fifth cycle, 1148 mL/g sample). However, regeneration improved the gas yield (1515 mL/g sample) owing to the redispersion of the aggregated Ni particles. These results reveal the potential for the continuous use of catalysts, advancing the possibility of recycling polyurethane waste.

Poly(ethylene terephthalate) (PET) pyrolysis products and those produced from their subsequent catalytic reactions under various metal oxides (ZnO, MgO, TiO2, and ZrO2) were evaluated qualitatively and semiquantitatively using a tandem μ-reactor gas chromatography–mass spectrometry (TR-GC/MS) system. The catalytic reaction products were analyzed in situ to determine the duration and temperature dependence of their production. In the TR-GC/MS, a reactor with two-tier, independent heat sources was linked directly to a GC/MS device. PET pyrolysis was carried out at 450 °C, whereas the pyrolysis products were reacted in the presence of metal oxides at 700 °C. ZnO, which has a high base strength, promoted decarboxylation of the principal pyrolysis products of benzoic acid and terephthalic acid (TPA) selectively and at a low temperature. The proportion of oil components made up by benzene was up to 88.8 area%. On the other hand, MgO, TiO2, and ZrO2have lower base strengths than ZnO. Hence, their capabilities for benzoic acid and TPA decarboxylation were low, and carboxylation using these oxides required temperatures 50–70 °C higher than that using ZnO. In summary, the present study found that benzene-rich aromatic hydrocarbons can be obtained by the catalytic pyrolysis of PET using various metal oxides and that the product composition depends on the acid–base properties of the metal oxides. These findings will help promote feedstock recycling to convert PET waste materials or mixed plastics that contain PET into raw chemical materials by pyrolysis.

The large-scale culture of human induced pluripotent stem cells (hiPSCs) is essential for developing new pharmaceuticals and regenerative therapy methods. While for the development of cultured meat products, mass production of animal myoblasts is necessary. Both hiPSCs and animal myoblasts consume d-glucose as their energy source and produce l-lactate, which accumulates in cell culture media and inhibits cell proliferation. To make large-scale cell culture economically feasible, l-lactate removal and subsequent reuse of media are of high importance. The adsorption technique is attractive for l-lactate removal due to its low cost, ease of operation, and scalability. The current study is dedicated to 4-(2-hydroxyethyl)-1-piperazineethanesulfonate (HEPES) intercalated Mg–Al layered double hydroxide (LDH), which acts as a biocompatible anion-exchanger in media. HEPES‧Mg–Al LDH was able to remove l-lactate from hiPS cells and myoblast-relevant media selectively while mostly retaining d-glucose. Adsorbent exhibited dose-dependent cytotoxicity to hiPSCs and C2C12 cells, mainly related to elevated osmolarity, HEPES, and Mg levels and adsorption of media micro components. By employing alternatively prepared sol-gel derived HEPES‧Mg–Al LDH, the required adsorbent dose for efficient l-lactate removal was reduced to a safe level. The current study thoroughly evaluates Mg–Al layered double hydroxides as suitable adsorbents for cell culture media regeneration and discusses the limitations of Mg–Al LDHs in systems relevant to hiPS cells and C2C12 cells. This work promotes the cost-effective large-scale production of cells and gives insight into the limitations of Mg–Al LDHs applied to systems of biological origin.

Most patients with acute eosinophilic pneumonia (AEP) show rapid improvement. However, some cases of AEP prove fatal. The aims of this study were to determine the clinical, radiographic, and pathologic characteristics of patients in whom AEP has a fatal outcome and to identify predictors of a poor prognosis.

The mass production of human induced pluripotent stem cells (hiPSCs) is important in the area of regenerative medicine. During proliferation, stem cells metabolize D-glucose into L-lactate, the accumulation of which in a cell culture medium impairs the mass production of cells. It is therefore important to supply D-glucose and remove L-lactate from the cell culture medium to ensure that the stem cell mass culture can be achieved. In the present study, L-lactate-selective Mg-Al layered double hydroxide (LDH) adsorbents containing celL-culture-compatible exchangeable anions were designed. More specifically, different stem cell nutrients (i.e., L-alanyL-L-glutamine, L-glutamine, L-serine, L-methionine, L-cysteine, L-glutamate and α-ketoglutarate) and the cell culture buffer component (i.e., 4-(2-hydroxyethyl)-1-piperazineethanesulfonate (HEPES)) were incorporated into the Mg-Al LDHs via a rehydration method. The orientations of the organic guests and the host–guest interactions were characterized using a range of analytical and computational techniques. It was deduced that the L-lactate adsorption ability of the LDHs and the selectivity over D-glucose depended on a number of factors, including the charge density of the LDH guest relative to L-lactate, the guest orientation and the hydrogen bonds formed in the host–guest, guest–guest and guest–host–glucose complexes. Overall, this study provides insights into the design of effective and potentially biocompatible adsorbents for cell culture media regeneration to promote the cost-effective mass production of stem cells.

Arsenic contamination in groundwater is an environmental problem that affects large populations on the global scale. The anion exchange material, Mg–Al layered double hydroxide (Mg–Al LDH) intercalated with NO3−, is an effective adsorbent for removing As(V) from aqueous solutions. In this study, we prepared Mg–Al LDH with a high anion exchange capacity by the co-precipitation method, and investigated its adsorption isotherm and reaction kinetics with As(V). The adsorption process is well described by the Langmuir model. The maximum adsorption capacities were determined to be 142.86 and 76.92 mg/g for LDHs synthesized with initial Mg/Al molar ratios of 2 and 4, respectively. The reaction kinetics of As(V) with Mg–Al LDH is demonstrated to be pseudo-second order, which indicates that chemisorption (i.e., anion exchange of HAsO42−with the intercalated NO3−) is the rate determining step. The values of the activation energy also indicate that anion exchange is the predominant adsorption mechanism.

EGFR exon 20 insertion mutations account for 5% to 10% of EGFR-mutated NSCLC. CLN-081 (formerly known as TAS6417), a novel covalent EGFR tyrosine kinase inhibitor, exhibits pan-mutation selective efficacy, including exon 20 insertions, in the clinical setting. Nevertheless, some patients may not respond to CLN-081 and resistance to CLN-081 may emerge over time in others.

Immunophenotyping of tumor-infiltrating lymphocytes (TILs) by flow cytometry can predict clinical efficacy of immunotherapy. However, several obstacles need to be overcome for developing a flow cytometry assay starting from solid tumor specimens. Here, we show a detailed enzyme-based protocol to isolate TILs from human tumor tissues. The protocol was optimized to obtain enough viable TILs from a biopsy tissue specimen for flow cytometry-based TIL immunophenotyping. Additionally, tissue samples could be preserved for up to 72 h for subsequent characterization.

Poly(ethylene terephthalate) (PET) was pyrolyzed in the presence of several metal hydroxides for the high-yielding recovery of benzene in one benzene-rich fraction. The highest benzene yield of 80.7% and a purity of 90.2 wt % were achieved in the presence of Ca(OH)2and Ba(OH)2, respectively. In addition, thermogravimetric–mass spectroscopic (TG-MS) measurements of metal terephthalates as the benzene precursors suggested a mechanism of benzene formation from metal terephthalates.

Lactate is an important metabolite generated during the culture of pluripotent stem cells and is known to inhibit the cell growth. With the increase in the prominence of pluripotent stem cell applications, reliable methods are required to remove metabolites such as lactate for enabling the high-density culture of cells. Herein, we report an investigation of layered double hydroxides (LDHs) and layered double oxides (LDOs) as anion-adsorbents for lactate removal to regenerate the cell culture medium. The lactate absorption ability of Cu-Al and Mg-Al LDH and Cu-Al and Mg-Al LDO adsorbents was evaluated. The influence of various process parameters, including temperature and pH, on the lactate adsorption, were investigated. The kinetics of the adsorption process and equilibrium dynamics were studied, and the maximum adsorption amounts were determined. The Cu-Al LDH, Cu-Al LDO, Mg-Al LDH, and Mg-Al LDO exhibited a lactate adsorption that followed a pseudo-second-order kinetic model, and their apparent activation energies for adsorption were 32.0, 47.4, 95.7, and 61.7 kJ/mol, respectively; these values indicated that chemical adsorption was the underlying mechanism of adsorption. The Langmuir and Freundlich models were analyzed and revealed the nature of the anion-exchange process. This study is expected to promote the high-density culture of cells by ensuring the regeneration of the media by the efficient removal of the undesired lactate.

Sulfate-contaminated water is a major environmental problem that alters the taste of water, disturbs the digestive systems of animals and humans, and erodes both soil and metals. In this study, the layered double hydroxide (LDH) 4Mg2Al.NO3and LDH 8Mg2Al.NO3were prepared using a co-precipitation technique, and applied in the adsorption of SO42-from an aqueous solution. The reaction is well described by the Langmuir adsorption model. LDH 4Mg2Al.NO3and LDH 8Mg2Al.NO3afforded maximum SO42-adsorption values of 135.14 and 92.59 mg/g, respectively. The reaction is best explained by a pseudo-second-order mechanism, which suggests that chemisorption is the rate-determining step. The activation energies of LDH 4Mg2Al.NO3and LDH 8Mg2Al.NO3indicate that the adsorption of SO42-on synthetic LDHs predominantly follows an anion-exchange mechanism, wherein SO42-ions in the aqueous medium replaces intercalated NO3-ions in the synthetic LDHs. The thermodynamic parameters (ΔH̊, ΔS̊, and ΔG̊) were also calculated. The reaction was endothermic, and the synthetic LDHs afforded feasible and spontaneous adsorption of SO42-.

The proportions of pyrolysis and hydrolysis in poly(ethylene terephthalate) (PET) degradation were determined from the decomposition of PET in 18O-labeled steam, producing labeled and unlabeled terephthalic acid. At a 100 vol % steam concentration at 400 °C, 74% of the ester bonds were pyrolyzed and 26% were hydrolyzed, as determined by gas chromatography-mass spectrometry. In addition, thermogravimetric analysis revealed the activation energy to be 199 kJ mol−1under pyrolytic conditions, decreasing with increasing steam concentration, and reaching a minimum of 132 kJ mol−1at 75 vol %.

To realize improved wastewater treatment processes, the study investigated the processing of boron and fluorine and the processing of real landfill leachate using MgO with different specific surface areas. By optimizing the MgO absorbent, the time required for boron and fluorine processing can be reduced dramatically and uniform wastewater quality standards can be achieved. The rate constants for boron and fluorine removal increased with both temperature and specific surface area. In the processing of actual wastewater, which contained many coexisting ions, MgO was successfully applied to the removal of boron.