Publication: Sentez gazından hafif olefin üretimine yönelik inorganik ve polimerik destekli demir ve demir borid katalizörlerin geliştirilmesi
Abstract
Olefinler, başta plastik olmak üzere otomotiv, ambalaj, tekstil ve elektronik gibi birçok sektöre hidrokarbon girdisi sağlayan önemli kimyasallardır. Petrol yağlarının benzin ve türevlerinin üretiminde uygulanan “parçalama (kracking) prosesi” sırasında hafif olefinler olarak adlandırılan etilen, propilen ve bütilen kimyasalları da elde edilmektedir. Petrol rezervlerinin sınırlı olması ve olefin kimyasallarına olan ihtiyacın nüfüs artışıyla orantılı olarak artması, petrole alternatif hammadde kaynaklarına olan talebi arttırmaktadır. Bu amaçla kömür, doğal gaz ve biyokütle gibi kaynaklar öne çıkmaktadır. Fischer-Tropsch’den olefin (FTO) prosesi, olefin üretimi için kullanılan katalitik bir prosestir. Kömür veya biyokütlenin gazlaştırılmasıyla elde edilen sentez gazının (CO+H2) katalizör eşliğinde reaksiyonu sonucu olefinler üretilmektedir. Bu bağlamda yüksek kükürt içeren Türk linyit kömürlerinin gazlaştırılmasıyla sentez gazı elde edilmesi ve bu sentez gazından olefin üretimi için katalizör geliştirilmesi önem arz etmektedir.Bu çalışmada, sentez gazından hafif olefinlerin üretimine yönelik demir bazlı katalizörlerin geliştirilmesi hedeflenmiştir. Tez kapsamında kullanılan katalizörler destekli/ desteksiz ve promotörlü/ promotörsüz olarak farklı yöntemler kullanılarak sentezlenmiştir. Sentezlenen katalizörlerin fiziksel ve yapısal özelliklerini inceleyebilmek için SEM-EDX, ICP, BET, XRD, XRF ve TGA gibi analiz yöntemleri kullanılarak karakterizasyon çalışmaları yapılmıştır.Reaksiyon testleri, yüksek basınç ve sıcaklıkta çalışma imkânı sunan Çoklu Yüksek Basınç Katalizör Test Sistemi’nde 340°C sıcaklık ve 10 bar basınç şartları altında gerçekleştirilmiştir. Reaksiyon sırasında sürekli olarak gaz analizleri alınmış ve katalizörlerin FTO reaksiyonunda göstermiş oldukları performanslar karşılaştırılmalı olarak incelenmiştir.Yapılan tüm testler sonucunda, poli(2,6-difenilfenilen-oksit) destekli ve potasyum promotörlü polimerik demir katalizörün (3K10FePPPO), %61.76 CO dönüşümü ve %55.14 C2-C4 olefin seçiciliği ile birlikte en iyi aktivite özelliklerine sahip olduğu belirlenmiştir. Bu sonuç, FTO prosesinde polimer katalizör kullanımı için umut vadetmektedir.
Olefins are important chemicals that provide hydrocarbon input to many industries such as automotive, packaging, textile and electronics, especially plastic. During the cracking process applied in the production of gasoline and derivatives of petroleum oils, ethylene, propylene and butylene chemicals called light olefins are also obtained. Due to the limited oil reserves and the need for olefin chemicals increasing in proportion to population growth, the demand for alternative raw material sources to oil is ascended. For this purpose, resources such as coal, natural gas and biomass come to the forefront.The process of olefin from Fischer-Tropsch (FTO) is a catalytic process used for olefin production. Olefins are produced by the reaction of the syngas (CO+H2) obtained by gasification of coal or biomass in the presence of catalysts. In this context, syngas producing by gasified of Turkey lignite coals which contains high sulfur and catalyst development for the production of olefins from syngas is significant.In this study, it is aimed to develop iron-based catalysts for the production of light olefins from syngas. Catalysts used in thesis were synthesized by using different methods as supported/ unsupported and with/ without promotor. In order to examine the physical and structural properties of synthesized catalysts, characterization studies were carried out by employing analysis methods such as SEM-EDX, ICP, BET, XRD, XRF and TGA. Reaction tests were performed under the conditions of 340°C temperature and 10 bar pressure in The High Throughput Screening Catalyst Test System which provides the opportunity to operate at high pressure and temperature. During the reaction gas analyzes were taken continuously and the performances of the catalysts in the FTO reaction were investigated comparatively.As a result of all the tests, it was determined that the polymeric iron catalyst (3K10FePPPO) with poly (2,6-diphenylphenylene-oxide) supported and potassium promoted had the best activity properties with 61.76% CO conversion and 55.14% C2-C4 olefin selectivity. This result is promising for the use of polymer catalysts in the FTO process.
Olefins are important chemicals that provide hydrocarbon input to many industries such as automotive, packaging, textile and electronics, especially plastic. During the cracking process applied in the production of gasoline and derivatives of petroleum oils, ethylene, propylene and butylene chemicals called light olefins are also obtained. Due to the limited oil reserves and the need for olefin chemicals increasing in proportion to population growth, the demand for alternative raw material sources to oil is ascended. For this purpose, resources such as coal, natural gas and biomass come to the forefront.The process of olefin from Fischer-Tropsch (FTO) is a catalytic process used for olefin production. Olefins are produced by the reaction of the syngas (CO+H2) obtained by gasification of coal or biomass in the presence of catalysts. In this context, syngas producing by gasified of Turkey lignite coals which contains high sulfur and catalyst development for the production of olefins from syngas is significant.In this study, it is aimed to develop iron-based catalysts for the production of light olefins from syngas. Catalysts used in thesis were synthesized by using different methods as supported/ unsupported and with/ without promotor. In order to examine the physical and structural properties of synthesized catalysts, characterization studies were carried out by employing analysis methods such as SEM-EDX, ICP, BET, XRD, XRF and TGA. Reaction tests were performed under the conditions of 340°C temperature and 10 bar pressure in The High Throughput Screening Catalyst Test System which provides the opportunity to operate at high pressure and temperature. During the reaction gas analyzes were taken continuously and the performances of the catalysts in the FTO reaction were investigated comparatively.As a result of all the tests, it was determined that the polymeric iron catalyst (3K10FePPPO) with poly (2,6-diphenylphenylene-oxide) supported and potassium promoted had the best activity properties with 61.76% CO conversion and 55.14% C2-C4 olefin selectivity. This result is promising for the use of polymer catalysts in the FTO process.