Recycling of enamelled copper wire from end-of-life electric motor via room temperature methanolysis

Polyester enamelled copper wire plays an important role in the manufacturing of electric motors. In line with the electrification of transport, the demand for electric motors and the future waste generated from their end-of-life cannot be ignored. The waste from the polyester enamelled copper wire is expected to increase steadily. Methods proposed by researchers are mainly focused on thermal treatment to either pyrolyse or burn off the polyester enamel. However, thermal treatments fail to consider the potential risk of air pollution and to recover the polyester enamel. In this manuscript, we propose two-stage processes comprised of methanol washing and room temperature methanolysis with dichloromethane as co-solvent and K2CO3 as catalyst to delaminate multilayered type enamelled copper wire. The methanol washing recovers polyvinyl butyral as it is, via dissolution. Whereas the methanolysis products are dimethyl terephthalate (DMT) and dimethyl isophthalate (DMI) which are precursors to the polyester and could be used to make new polyester. At room temperature, the parameters of solid to liquid, DCM to methanol, and K2CO3 to Cu ratio, of 500 g/L, 1.00 mol/mol, and 0.10 wt%, respectively, allow complete removal of polyester enamel in 24 h. The methanolysis parameters described manage to give a modest DMT and DMI yield of 86.0% and 92.2%, respectively. The reaction time can be sped up by increasing the temperature by 10 °C, leading to complete depolymerisation in 4 h. Compared to thermal treatment, the proposed method requires 80.7% lower energy with the products contained within the solution

Chlorine removal from the pyrolysis of urban polyolefinic waste in a semi-batch reactor

The pyrolysis of urban chlorine-containing polyolefinic plastic waste with simultaneous retention of HCl is investigated. Different chemical removers based on sodium, calcium and zinc bases, and different adsorbents based on alumina or zeolites were used inside the reactor or in downstream hot filters, respectively, for chlorine removal and upgrading of pyrolysis oils. Initially, polyolefin waste (POW, containing a 98.5 wt% polyolefins) was thermogravimetrically pyrolyzed to determine its thermal behaviour. Subsequently, chemical removers were mixed with the POW which was pyrolyzed at 480 °C in a semi-batch reactor. The adsorbents were tested separately in hot filters (300 ± 20 °C) downstream of the pyrolysis reactor. After the pyrolysis, the resulting char containing the chemical removers and the absorbents in the hot filters were analysed by FTIR, CHN elemental analysis and ESEM-EDS to determine their respective chlorine contents. The highest chlorine retention was 23.8 wt% for chemical remover when used in direct contact with POW, while a zeolite used in the hot filter (gas streams) gave a chlorine retention of 65.6 wt%. The pyrolytic liquids consisted of mixtures of C7-C40 hydrocarbons made up of olefinic and aliphatic hydrocarbons with a very low presence of aromatics (estimated to be below 3 wt% by HPLC). In most cases, the chlorine removal processes resulted in waxier pyrolytic oils and with a higher degree of branchin

Reduction of aerobic and lactic acid bacteria in dairy desludge using an integrated compressed CO2 and ultrasonic process

International audienceAbstractCurrent treatment routes are not suitable to reduce and stabilise bacterial content in some dairy process streams such as separator and bactofuge desludges which currently present a major emission problem faced by dairy producers. In this study, a novel method for the processing of desludge was developed. The new method, elevated pressure sonication (EPS), uses a combination of low frequency ultrasound (20 kHz) and elevated CO2 pressure (50 to 100 bar). Process conditions (pressure, sonicator power, processing time) were optimised for batch and continuous EPS processes to reduce viable numbers of aerobic and lactic acid bacteria in bactofuge desludge by ≥3-log fold. Coagulation of proteins present in the desludge also occurred, causing separation of solid (curd) and liquid (whey) fractions. The proposed process offers a 10-fold reduction in energy compared to high temperature short time (HTST) treatment of milk

Hydrochloric acid removal from the thermogravimetric pyrolysis of PVC

A powder characterization method was developed to screen the ability of a range of chemicals and absorbents to retain chlorine from chlorinated plastic pyrolysis. The behaviour of adsorbents such as Al2O3 and zeolites, and chemical removers based on NaHCO3, CaO and Na2CO3-ZnO were studied for the removal of HCl released during PVC pyrolysis. First, chlorine removers are mixed with PVC and tested in a thermobalance under pyrolysis conditions for the complete PVC dehydrochlorination (550 °C). Subsequently, after the release of HCl, CO2 and H2O, the chars are analysed by FTIR, CHN elemental analysis and ESEM-EDS to determine the retention of chlorine on the chlorine removers. According to FTIR and CHN, PVC pyrolysis occurs through dehydrochlorination and the formation of aromatics. FTIR and EDS were used to follow the consumption of the bases present in the chemical removers and the suppression of the CCl absorption bands of the PVC CHCl groups during pyrolysis, as well as the formation of the resulting salts (NaCl, CaCl2 and ZnCl2). The chemical removers exhibited chlorine retentions of up to 71 wt. % (using Na2CO3-ZnO), while the adsorbents presented a maximum of 19 % of retention at 550 °C and heating rate of 200 °C/min

Understanding the dechlorination of chlorinated hydrocarbons in the pyrolysis of mixed plastics

The dechlorination of chlorine containing hydrocarbons in pyrolysis vapor is poorly understood. In order to shed new light on the dechlorination mechanism, a model mixture composed of iso-octane doped with 2-chlorobutane, 2-chloroethylbenzene, and chlorobenzene was used to study the dechlorination of chlorinated hydrocarbons by alkali adsorption. These three chlorinated hydrocarbons were selected as they can be typically produced from the pyrolysis of mixed plastic waste containing polyvinyl chloride (PVC). The mixture is pumped continuously through a Na2CO3 or CaCO3/alumina bed, and GC-MS is used to identify the dechlorination products and to follow the dechlorination reactions. When chlorine is bonded to an aliphatic carbon with an adjacent aliphatic hydrogen, the chlorinated compound first undergoes a dehydrochlorination reaction to form HCl and olefins, and subsequently the HCl is reacted with the alkali in the absorbents. In our experiments, 2-chlorobutane is converted to 2-butene, and 2-chloroethylbenzene is converted to styrene. The formation of HCl and subsequent reaction with alkali components in the absorbent is verified by IR spectroscopy and XRD. In the presence of an alkali, the aliphatic chlorinated hydrocarbons underwent dechlorination at a temperature of 180 °C. The removal of chlorine from aromatic chlorinated compounds operates in a different mechanism, in which the C–Cl bond scission is promoted significantly by the presence of an alumina and hydrocarbon medium. It was found that chlorobenzene undergoes dechlorination forming phenol and benzene

An Examination of Celtic Craft and the Creative Consciousness as a Contribution to Marketing Creativity

Examination of the Celtic craft sector identifies a creative form of marketing which has its foundations in imagination, intuition and innovation, rather than the linear prescriptions of formal marketing frameworks and language which still dominate contemporary marketing management texts. The creative marketing competencies identified in the sector are also grounded within a wider creative marketing paradigm where experimental forms of marketing are encouraged, postmodern ideals are embraced and artistic philosophy and practice encouraged. The controlled Saxon influenced Marketing Establishment is challenged by the freer, more creative fringe of Celtic marketing as the avant garde

Roadmap for a sustainable circular economy in lithium-ion and future battery technologies

The market dynamics, and their impact on a future circular economy for lithium-ion batteries (LIB), are presented in this roadmap, with safety as an integral consideration throughout the life cycle. At the point of end-of-life (EOL), there is a range of potential options—remanufacturing, reuse and recycling. Diagnostics play a significant role in evaluating the state-of-health and condition of batteries, and improvements to diagnostic techniques are evaluated. At present, manual disassembly dominates EOL disposal, however, given the volumes of future batteries that are to be anticipated, automated approaches to the dismantling of EOL battery packs will be key. The first stage in recycling after the removal of the cells is the initial cell-breaking or opening step. Approaches to this are reviewed, contrasting shredding and cell disassembly as two alternative approaches. Design for recycling is one approach that could assist in easier disassembly of cells, and new approaches to cell design that could enable the circular economy of LIBs are reviewed. After disassembly, subsequent separation of the black mass is performed before further concentration of components. There are a plethora of alternative approaches for recovering materials; this roadmap sets out the future directions for a range of approaches including pyrometallurgy, hydrometallurgy, short-loop, direct, and the biological recovery of LIB materials. Furthermore, anode, lithium, electrolyte, binder and plastics recovery are considered in order to maximise the proportion of materials recovered, minimise waste and point the way towards zero-waste recycling. The life-cycle implications of a circular economy are discussed considering the overall system of LIB recycling, and also directly investigating the different recycling methods. The legal and regulatory perspectives are also considered. Finally, with a view to the future, approaches for next-generation battery chemistries and recycling are evaluated, identifying gaps for research. This review takes the form of a series of short reviews, with each section written independently by a diverse international authorship of experts on the topic. Collectively, these reviews form a comprehensive picture of the current state of the art in LIB recycling, and how these technologies are expected to develop in the future

Effects of Instrumentation Recorder time Base Error on Spectral Purity

International Telemetering Conference Proceedings / October 13-15, 1970 / International Hotel, Los Angeles, CaliforniaExperimental data is presented to show how carrier amplitude of a recorded signal is affected by Time Base Error. Time Base Error effects on the sideband structure of a recorded signal are also shown for different amounts of Time Base Error and at several frequencies. The effect of capstan servo adjustment on spectral purity demonstrates the need for new methods of performance evaluation to achieve optimum performance when recording spectrum information. The data presented shows that skew (ITDE) has little effect on spectral purity for analysis bandwidths of 50 Hz or greater.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection