Hidrokarburo likidoen ekoizpena etilenoaren oligomerizazioaren bitartez

Abstract

Ethylene is the most demanded light olefin within petrochemical industry, with an increasing annual rate of 3,4% on its demand. Due to the availability of natural gas, ethane’s price has shown a drastic decrease worldwide and, therefore, ethane steam cracking (SC) units are beind boosted within refineries, where ethylene is the main product. This situation has led to an excess of ethylene production, while the deficit on propylene production has increased. Therefore, the valorization of ethylene by oligomerization brings the opportunity to obtain high-added valued products, such as, higher olefins, transportation fuels (gasoline, jet fuel and diesel) and/or aromatics; which has increased the interest in both refiner-ies and petrochemical industries. Appart from facing the excess of ethylene production, the ethylene used in the oligomerization process, can be produced from more sustainable sources (i.e. by CO2 valorization). Hence, oligomerization products, particularly fuels, will be free of sulfur and heteroatoms, and thus, they will show a lower level of toxicity as well as a lower environmental impact in comparison to those derived from fossil fuels. In this work, the main applications of ethylene and the main technologies for ethylene production (conventional and more sustainable ones) are firstly analyzed. Then, ethylene oligomerization technologies which are available in industry are described, where different types of catalysts, operating conditions (temperature and pressure) and the reaction mechanism are explained. Finally, the main facts that relate ethylene oligomerization to Sustainable Development Goals (SDGs) are analyzed.; Etilenoa industria petrokimikoko olefina arinen merkatuan liderra da, eta haren eskaria urtean % 3,4 igo-tzen da. Gas naturalaren eskuragarritasuna dela eta, etanoaren prezioak beherakada nabarmena izan du mundu-mailan eta horrek findegietan etanoaren ur-lurrun bidezko cracking termiko (SC) izeneko prozesuaren erabilera areagotu du, non eti-lenoa ekoizten den nagusiki. Horrek findegietan etilenoaren gaindikina izatea eragin du, eta areagotu egin du propilenoaren ekoizpenean dagoen defizita. Hori horrela, etilenoa oligomerizazioaren bitartez balorizatzeak balio erantsiko produktuak ekoiztea ahalbidetzen du, hala nola olefina astunak, erregaiak (gasolina, jet fuela eta diesela) edota aromatikoak; beraz, interesa piztu du gaur egungo findegietan zein industria petrokimikoetan. Izan ere, etilenoaren gaindikinari aurre egiteaz gain, oligomerizazioan erabilitako etilenoa iturri jasangarrietatik baldin badator, esate baterako CO2-aren balorizaziotik, lortutako oligomerizazio-produktuek, bereziki erregaiek, ez dute sufrerik izango, ezta heteroatomorik ere; beraz, toxikotasun-maila askoz baxuagoa izango dute, eta jatorri fosiletik lortutako erregaiek baino inpaktu txikiagoa ingurumenean. Artikulu honetan, lehendabizi etilenoaren erabilerak, ohiko teknologiak eta teknologia berriztagarriagoak laburki azaldu dira. Jarraian, etile-noaren oligomerizaziorako industrian ezarrita dauden teknologiak deskribatu dira, katalizatzaile motak, operazio-baldintzak(tenperatura eta presioa) eta erreakzio-mekanismoa aztertuz. Azkenik, etilenoaren oligomerizazioak eta garapen jasangarrirako helburuen (GJHen) arteko harremana erlazionatzen duten gakoak laburbildu dira.