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Gorka Elordi

Bio: Gorka Elordi is an academic researcher from University of the Basque Country. The author has contributed to research in topics: Pyrolysis & High-density polyethylene. The author has an hindex of 22, co-authored 35 publications receiving 2167 citations.

Papers
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TL;DR: In this article, a Pinewood sawdust flash pyrolysis has been performed in continuous mode in a pilot plant provided with a conical spouted bed reactor, in the 400-600°C range.
Abstract: Pinewood sawdust flash pyrolysis has been performed in continuous mode in a pilot plant provided with a conical spouted bed reactor, in the 400–600 °C range. The influence of temperature on the pyrolysis yields and product properties has been studied. Product analysis has been carried out on-line by means of chromatographic methods. High liquid yields have been achieved, with the maximum bio-oil yield (75 wt%) at 500 °C. Gas yield is very low at low temperatures and this fraction is mainly composed of carbon dioxide, carbon monoxide and small amounts of methane, hydrogen and C2–C4 hydrocarbons. Bio-oil has been characterized and its major compounds are phenols, specifically guaiacols at low temperatures and catechols at high temperatures. At 600 °C, there is an increase in light compounds due to the cracking reactions, but no aromatic compounds have been detected due to the low residence time of the volatiles in the reactor. The fuel properties of the bio-oil have been measured and the results indicate that it can be a potential substitute to conventional fuels, although its heating value should be improved by subjecting to further treatments. Char can be used as energy source or as active carbon. The char obtained at 600 °C has a high surface area and is suitable for active carbon production.

288 citations

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TL;DR: In this article, the effect of the zeolite structure (HZSM-5, Hβ and HY) on coke deposition during the cracking of high-density polyethylene has been studied by combining the results of multiple spectroscopic and analytical techniques: FTIR, Raman, UV-vis, 13 C NMR and coke extraction.
Abstract: The effect of the zeolite structure (HZSM-5, Hβ and HY) on coke deposition during the cracking of high-density polyethylene has been studied by combining the results of multiple spectroscopic and analytical techniques: FTIR, Raman, UV–vis, 13 C NMR and coke extraction, followed by GC-MS and 1 H NMR analysis. In addition, by combining FTIR and temperature programmed oxidation (TPO) analysis we obtained information on the coke: properties, burn-off, and changes in composition during catalyst regeneration. Samples of the spent catalysts were obtained in a state-of-the-art pilot plant (conical spouted bed reactor) after the continuous treatment of 900 g (1 g min −1 , 15 h) of high-density polyethylene at 500 °C, using 30 g of catalyst. The results show that as the pore diameter of the zeolite is increased, bimolecular reactions (hydrogen transfer and oligomerizations), condensations and cyclizations are enhanced, yielding more aromatic coke. Furthermore, the pore topology of the HZSM-5 zeolite improves the flow of coke precursors (also favored by the high flow rate of N 2 ) to the outside of the catalyst; viz. HZSM-5 catalyst preserves its activity for longer.

194 citations

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TL;DR: In this article, thermal pyrolysis of three different polyolefin plastics (HDPE, LDPE and PP) has been carried out in a conical spouted bed reactor.

186 citations

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TL;DR: In this paper, a study has been carried out using HZSM-5, HY and Hβ zeolite-based catalysts in the pyrolysis of high density polyethylene (HDPE) continuously fed into a conical spouted bed reactor (CSBR) at 500°C and atmospheric pressure, with the aim being to assess the yields and composition of the main products (both light olefins and automotive fuel hydrocarbons).

186 citations

Journal ArticleDOI
TL;DR: In this paper, the deactivation of three different catalysts used in the cracking of high density polyethylene (HDPE) has been compared and the results of temperature program combustion and transmission electron microscopy show that coke growth is hindered in the HZSM-5 zeolite pore structure.
Abstract: The deactivation of three different catalysts used in the cracking of high density polyethylene (HDPE) has been compared. The catalysts used are HZSM-5, Hβ and HY zeolites agglomerated with bentonite and alumina. The reactions have been carried out in a conical spouted bed reactor at 500 °C, and plastic (high density polyethylene) has been fed in continuous mode (1 g min−1) for up to 15 h of reaction. The HZSM-5 zeolite catalyst gives way to high yields of C2–C4 olefins (57 wt%) and, moreover, it is the one least influenced by deactivation throughout the run, which is explained by the lower deterioration of its physical properties and acidity. The results of temperature program combustion and transmission electron microscopy show that coke growth is hindered in the HZSM-5 zeolite pore structure. The high N2 flow rate used in the conical spouted bed reactor enhances coke precursor circulation towards the outside of the zeolite crystal channels.

154 citations


Cited by
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TL;DR: In this article, the pyrolysis process for each type of plastics and the main process parameters that influenced the final end product such as oil, gaseous and char were reviewed.

1,150 citations

Journal ArticleDOI
TL;DR: The existing techniques of pyrolysis, the parameters which affect the products yield and selectivity and the influence of different catalysts on the process are presented and major research gaps in this technology are identified.

687 citations

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TL;DR: A mesoporous carbon developed from waste tire rubber was used as an adsorbent for the removal and recovery of a hazardous azo dye, Acid Blue 113 and Kinetic studies indicated that the adsorption process follow first order kinetics and particle diffusion mechanisms are operative.

613 citations

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TL;DR: This review highlights the use of waste-tires derived carbon to remove various types of pollutants like heavy metals, dye, pesticides and others from aqueous media.

613 citations

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TL;DR: In this paper, a comprehensive review has been carried out in order to show the effects of the main process conditions (heating rate, temperature, pressure, carrier gas flow rate and type, volatiles residence time and pyrolysis time) on physicochemical properties and distributions of the resulting products (gas, liquid and solid fractions).
Abstract: This review deals with the state-of-the-art of waste tyre pyrolysis for the first time in literature. Pyrolysis has been addressed as an attractive thermochemical process to tackle the waste tyre disposal problem while allowing energy recovery. Pyrolysis enables the separation of carbon black from tyres and the volatile matter released (condensable and non-condensable compounds) has the potential of renewable energy recovery given the significant proportion of natural rubber present in the tyre. Given this waste-to-energy pathway, a comprehensive review has been carried out in order to show the effects of the main process conditions (heating rate, temperature, pressure, carrier gas flow rate and type, volatiles residence time and pyrolysis time) on the physicochemical properties and distributions of the resulting products (gas, liquid and solid fractions). It has also been reviewed the influence of the size and composition of the feedstock. All reported results have been framed regarding the type of reactor as well as the experimental conditions used to avoid contradictions among the large number of publications on the subject. It is shown that the occurrence of secondary reactions is very sensitive to the interaction of the aforementioned variables. Also, the main properties of the pyrolytic products are pointed out. The liquid and gaseous fractions obtained are a valuable fuel source; while the solid fraction (char) has the recovery potential of low- grade carbon black or as carbon adsorbent after applying an activation step. Special attention has been given to the liquid fraction, highlighting its properties as alternative fuel in compression ignition engines.

596 citations