H2S’ÜN ELEMENTEL KÜKÜRDE SEÇİCİ OKSİDASYONUNDA Ti-V-Cr ve Ti-V-Fe KATALİZÖRLERİ

Yıl 2018, Cilt: 23 Sayı: 2, 167 - 182, 31.08.2018

H. Mehmet Taşdemir

https://doi.org/10.17482/uumfd.358520

Öz

Bu çalışmada kompleksleştirme yöntemiyle eşmolar
oranda Ti-V-Fe ve Ti-V-Cr katalizörleri sentezlenmiş ve H₂S’ün
seçici oksidasyon reaksiyonuyla elementel kükürt eldesindeki aktiviteleri
incelenmiştir. Katalizörlerin katalitik aktiviteleri dolgulu kolon reaktör
sisteminde farklı sıcaklık (200°C, 250°C, 300°C) ve stokiyometrik gaz (O₂/H₂S:0,5)
bileşiminde incelenmiştir. Katalizörlerin yapısal özellikleri N₂
adsorpsiyon-desorpsiyon, XRD, TPR, SEM-EDS analizleri ile belirlenmiştir.
Sentezlenen katalizörlerin mezogözenekli yapıya sahip olduğu tespit edilmiştir.
Ti-V-Cr katalizörünün kristal yapısı TiO₂’in rutile fazı ve Cr₂O₃
bileşiklerinden oluşurken, Ti-V-Fe katalizörü kompleks bir kristal yapı
sergilemiştir. Bu katalizörün yapısında Fe₂TiO₅, V₂O₅,
FeV₂O₄, rutile TiO₂ ve Fe₂O₃
bileşikleri görülmüştür. Sentezlenen her iki katalizörle de 250°C reaksiyon
sıcaklığında % 100 H₂S dönüşümü elde edilmiştir. Reaksiyon
sıcaklığındaki artış ve azalış katalizörlerde elde edilen H₂S
dönüşümünde azalmaya sebep olmuştur. Bunun yanı sıra çalışılan tüm şartlarda
her iki katalizörle de oldukça yüksek (≥% 97) elementel kükürt seçiciliği elde
edilmiştir.  Özellikle 200°C sıcaklıkta,
yapısında kompleks bileşikleri içeren Ti-V-Fe katalizörü ile (% 73 H₂S
dönüşümü) Ti-V-Cr katalizörüne kıyasla (% 51 H₂S dönüşümü) daha
yüksek dönüşüm elde edilmiştir. 

Anahtar Kelimeler

Katalizör, H2S, Seçici oksidasyon, elementel kükürt

Ti-V-Cr and Ti-V-Fe Catalysts for H2S Selective Oxidation to Elemental Sulfur

Öz

In this study, Ti-V-Fe and Ti-V-Cr catalysts
were synthesized by complexation method and their activities were investigated
for H₂S selective oxidation reaction to elemental sulfur. Structural
properties of the catalysts were determined by N₂
adsorption-desorption, XRD, TPR, SEM-EDS analyzes. According to the analysis
results, it has been found that the synthesized catalysts have a mesoporous
structure. Ti-V-Fe catalyst exhibits a complex crystal structure, while the
crystal structure of the Ti-V-Cr catalyst is comprised of the rutile phase of
TiO₂ and Cr₂O₃ compounds. In this catalyst
structure, Fe₂TiO₅, V₂O₅, FeV₂O₄,
rutile TiO₂ and Fe₂O₃ compounds were observed.
The catalytic activities of the catalysts were investigated in a packed column
reactor system at different temperatures (200°C, 250°C, 300°C) and
stoichiometric gas composition (O₂/H₂S:0.5). 100% H₂S
conversion was obtained at 250°C reaction temperature with both catalysts
synthesized. The increase and decrease in the reaction temperature led to a
decrease in the conversion of H₂S obtained with the catalysts due to
the increase in sulfur deposition in the catalyst structure. In addition, under
all conditions studied, elemental sulfur selectivity was high (≥ 97%) with both
catalysts. Espe,cially at 200°C, a higher conversion was obtained with Ti-V-Fe (73%
H₂S conversion) catalyst which has complex compounds in the
structure compared to Ti-V-Cr catalyst (51% H₂S conversion).

Anahtar Kelimeler

Catalyst, H2S, Selective oxidation, Elemental sülfür

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