No abstract

The addition of plastics to the steam pyrolysis/gasification of wood sawdust with and without a Ni/Al 2 O 3 catalyst was investigated in order to increase the production of hydrogen in the gaseous stream. To study the influence of the biomass/plastic ratio in the initial feedstock, 5, 10 and 20 wt. % of polypropylene was introduced with the wood in the pyrolysis reactor. To investigate the effect of plastic type, a blend of 80 wt. % of biomass and 20 wt. % of either polypropylene, high density polyethylene, polystyrene or a mixture of real world plastics was fed into the reactor. The results showed that a higher gas yield (56.9 wt.%) and a higher hydrogen concentration and production (36.1 vol.% and 10.98 mmol. H 2 g -1 sample, respectively) were obtained in the gaseous fraction when 20 wt. % of polypropylene was mixed with the biomass. This significant improvement in gas and hydrogen yield was attributed to synergetic effects between intermediate species generated via co-pyrolysis. TheNi/Al 2 O 3 catalyst dramatically improved the gas yield as well as the hydrogen concentration and production due to the enhancement of water-gas-shift and steam reforming reactions.Very low amounts of coke (less than 1 wt. % in all cases) were formed on the catalyst during reaction, with the deposited carbonaceous material being of the filamentous type. The Ni/Al 2 O 3 catalyst was shown to be effective one hydrogen production in the copyrolysis/gasification process of wood sawdust and plastics.

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.

Abstract. Paclitaxel/carboplatin chemotherapy for cancer (TC therapy) exhibits neurotoxicity and causes peripheral neuropathy at a high frequency, which is difficult to cope with. In this study, we investigated the efficacy of Goshajinkigan, a traditional Japanese herbal medicine, for TC therapy-induced peripheral neuropathy. The subjects included in our study were patients with ovarian or endometrial cancer who underwent TC therapy and developed peripheral neuropathy. The patients were randomly divided into Group A, comprising of 14 patients (vitamin B12 treatment), and Group B, comprising of 15 patients (vitamin B12 + Goshajinkigan treatment). The observation period was 6 weeks following treatment initiation, and the evaluation items were as follows: i) the current perception threshold (CPT value) of the peripheral nerve, ii) visual analogue scale for numbness, iii) National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 grade of neurotoxicity, and iv) a questionnaire on the subjective symptoms of peripheral neuropathy (functional assessment of cancer therapy-taxane). These were compared between the groups and no significant differences were noted in any item. However, CTCAE grade 3 neurotoxicity developed in 2 patients (14.3%) after 6 weeks of administration in Group A, whereas no neurotoxicity was observed in Group B. When the change in the frequency of abnormal CPT ratio at 6 weeks of administration from that before treatment was compared between the groups, the frequency of abnormal value was significantly lower in Group B than in Group A (p<0.05). This suggests that Goshajinkigan inhibits the progression of peripheral neuropathy.

The decomposition of PET during thermal treatment of municipal waste results in the formation of sublimating substances such as terephthalic acid (TPA) and benzoic acid, causing blockage and corrosion of pipes in the treatment facilities. To prevent these effects, TPA can be decarboxylated in the presence of calcium oxide (CaO) to obtain benzene as the main product. However, high concentrations of TPA cause the formation of large char fractions, reducing the yield of desired products. In this investigation, TPA was decarboxylated using a fixed-bed reactor filled with CaO. To increase the yield of benzene and reduce the carbonaceous residue, the effects of pyrolysis temperature and TPA feed rate were investigated. The best results were achieved at 500 °C and a TPA feed rate of 51 mg L -1 , yielding 67% benzene with a purity of 99.2% and a carbonaceous residue containing 18% of the initial carbon.

No abstract

Plastics are essential materials for various products such as packaging and containers, electrical and electronic equipment, and automobiles. Japanese production of polymers was reported as 10.6 million t in 2014 1) , with the majority prepared from finite fossil resources. Currently, in excess of 150 and 200 different types of polymers and additives, respectively, are produced and distributed within Japan 2 ) . Metals and fillers are further mixed with these products to achieve the desired properties, giving innumerable combinations. Thus, no single recycling technique can treat all types of waste plastics. Consequently, waste plastics are commonly treated by mechanical recycling, feedstock recycling, and energy recovery, depending on the waste composition and the purpose of the recycled products.The Plastic Waste Management Institute reported that 9.3 million t of waste plastics were collected in 2014 in Japan 1 ) . The utilized rate (mechanical recycling feedstock recycling energy recovery) for collected waste plastics was 83 %, and is increasing yearly. Utilization can be broken down into 70 % energy recovery, 26 % mechanical recycling, and 4 % feedstock recycling. According to the Basic Law for Establishing the Recycling-based Society, the order of priority of these techniques is as follows: mechanical recycling feedstock recycling energy recovery. Therefore, the ideal and actual situations show a wide gap.Feedstock recycling is a growing field in Japan, but is challenging due to the mismatch with current domestic recycling systems. However, advances in research and technical development show the potential to achieve an advanced recycling-based society. In Japan, monomerization, blast furnace reduction, coke oven chemical feedstock recycling, liquefaction, and gasification are categorized as feedstock recycling. In this paper, we focus on liquefaction and gasification, which are based on the pyrolysis technique.Pyrolysis converts polymeric materials into gases, liquids, and solids at high temperatures in the absence of oxygen. This process cleaves various chemical bonds in polymers and additives by the action of only heat, which is advantageous for low-purity waste that cannot be treated by mechanical recycling. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) are the main polymeric materials produced worldwide, so have been widely studied. In addition, these materials are good quality carbon and hydrogen resources (PE and PP: 86 % C and 14 % H; PS: 92 % C and 8 % H). In contrast, the pyrolysis of polyvinyl chloride (PVC) and poly(ethylene terephthalate) (PET) Recycling of waste plastics is essential for reducing environmental degradation and ensuring future resource security. The quantity of domestic plastic waste recycled is increasing yearly, reaching 83 % in 2014. However, only 26 % and 4 % of the recycled waste plastic is treated by mechanical and feedstock recycling, respectively, whereas 70 % is treated by energy recovery (incineration). Therefore, the mechanical and feedstock recycling ra...

The possibility of simultaneous recovery of benzene and metals from the hydrolysis of poly(ethylene terephthalate) (PET)-based materials such as X-ray films, magnetic tape, and prepaid cards under a steam atmosphere at a temperature of 450 °C was evaluated. The hydrolysis resulted in metal-containing carbonaceous residue and volatile terephthalic acid (TPA). The effects of metals and additives on the recovery process were also investigated. All metals were quantitatively recovered, and silver, maghemite (γ-Fe2O3), and anatase (TiO2) were recovered without any changes in their crystal structures or compositions. In a second step, TPA was decarboxylized in the presence of calcium oxide (CaO) at 700 °C, producing benzene with an average yield of 34% and purity of 76%. Maghemite (γ-Fe2O3) incorporated in magnetic tape and prepaid cards could decarboxylate TPA. Aluminum present in the prepaid cards produced hydrogen by the reaction with steam. However, the presence of metals had no adverse influence on the recovery of benzene-rich oil in the presence of CaO. Therefore, this method can be applied to PET-based materials containing inorganic substances, which cannot be recycled effectively otherwise.