Orhan BAYTAR, Selman AĞRAK, Halil DEMİR, Ömer ŞAHİN

SODYUM BOR HİDRÜRÜN HİDROLİZİNDE KARBON NANOTÜP DESTEKLİ Co-Cr-B KATALİZÖRÜN KULLANILMASI

Artan teknoloji ile birlikte hem enerji ihtiyacı artmakta hem de mevcut fosil yakıtların miktarı gün geçtikçe azalmaktadır. Fosil yakıtların azalması ve enerji ihtiyacının artması araştırmacıları yenilenebilir enerji kaynakları için araştırmaya yönlendirmiştir. Hidrojen enerjisi bu yenilenebilir enerji kaynaklardan bir tanesidir. Sodyum borhidrür(NaBH4) hidrojen taşıyıcısıdır. Sodyum borhidrür hidrolizinde açığa çıkan hidrojenin yarısının sudan gelmesi büyük bir avantajdır. Bu çalışmada, NaBH4 hidrolizinde kullanılmak üzere karbon nanotüp destekli(KNT) Co-Cr-B katalizörü sentezlenmiştir. Sentezlenen katalizörün karakterizasyonu SEM, EDX, XRD ve BET ile gerçekleştirilmiştir. NaBH4 hidrolizinde NaOH konsantrasyonu, NaBH4 konsantrasyonu, katalizör miktarı ve sıcaklık parametrelerin etkisi incelenmiştir. Desteksiz Co-Cr-B katalizörün hidrojen üretim hızı 3560 ml.g-1.dk-1. iken KNT destekli Co-Cr-B katalizörün hidrojen üretim hızı 6600 ml.g-1.dk-1. olarak belirlenmiştir. NaBH4 hidroliz aktivasyon enerjisi ve kinetiği tespit edilmiş ve sırasıyla 55,88 kj/mol ve 0,2 olduğu tespit edilmiştir.

Anahtar Kelimeler:

Sodyum borhidrür, hidroliz, KNT, Co-Cr-B katalizör

Use of Carbon Nanotube Supported Co-Cr-B Catalyst in the Hydrolysis of Sodium Borohydride

With the increasing technology, the need for energy increases and the amount of fossil fuels available decreases over time. The decrease in fossil fuels and the increase in energy needs have prompted researchers to find new sources for renewable energy sources. Hydrogen energy is one of these renewable energy sources. Sodium borohydride (NaBH4) is a good source and carrier of hydrogen. Half of the hydrogen released in the hydrolysis of NaBH4 comes from water, which is a great advantage. In this study, carbon nanotube(CNT) supported Co-Cr-B catalyst was synthesized to be used in NaBH4 hydrolysis. The characterization of the synthesized catalyst was carried out with SEM, EDX, XRD and BET. The effects of parameters such as NaOH concentration, NaBH4 concentration, amount of catalyst and temperature on NaBH4 hydrolysis were investigated. While the hydrogen production rate of the unsupported Co-Cr-B catalyst was 3560 ml.g-1.dk-1, the hydrogen production rate of the CNT supported Co-Cr-B catalyst was determined as 6600 ml.g-1.dk-1. The kinetic order of hyrolysis and activation energy of NaBH4 were found as 0.2 and 55.88 kJ/mol, respectively.

Keywords:

Sodium borohydride, hydrolysis, CNT, Co-Cr-B catalyst,

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