Influence of Ni Species of Ni/AC Catalyst on Its Desulfurization Performance at Low Temperature

A series of Ni/AC catalyst samples were prepared by excessive impregnation, and the desulfurization activity of Ni/AC calcined at different temperatures was investigated. The Ni species on the Ni/AC catalyst calcined at different temperatures were studied by X-ray diffraction and X-ray photoelectron spectroscopy. The characterization results showed that the Ni species on the catalyst calcined at 400 °C is Ni2O3. After calcination at 550 °C, NiO species is formed on the activated carbon. NiO and Ni coexist on the Ni/AC catalyst calcined at 800 °C, and only pure Ni species is observed after calcination at 1000 °C. This suggested that Ni can form different chemical states on the Ni/AC catalyst calcined at different temperatures. The desulfurization test results showed that the catalysts calcined at 550 and 800 °C exhibit good desulfurization activity, whereas the catalyst calcined at 400 °C has poor activity, indicating that different chemical states of Ni on the Ni/AC catalyst show different desulfurization performance, and NiO is the main active phase of the Ni/AC catalyst.

摘要采用过量浸渍法制备了䜕Ni/AC䜕催化剂,䜕考察了不同焙烧温度对䜕Ni/AC䜕脱硫活性的影响,䜕并通过䜕X䜕射线衍射和䜕X䜕射线光电子能谱对催化剂进行了表征,䜕研究了经不同温度焙烧后的催化剂上的䜕Ni䜕物种形态及其对催化剂性能的影响.䜕䜕结果表明,䜕经䜕400䜕䜕焙烧后的催化剂中䜕Ni䜕物种为䜕Ni2O3,䜕550䜕C䜕焙烧后出现了䜕NiO䜕物种,䜕800䜕°C䜕焙烧后䜕Ni䜕物种变为䜕NiO䜕和䜕Ni䜕共存,䜕而䜕1 000䜕°C䜕焙烧后只存在单质䜕Ni.䜕䜕这说明不同温度焙烧后的催化剂中䜕Ni䜕形成了不同的化学形态.䜕䜕脱硫活性的测试结果表明,䜕经䜕550䜕°C䜕和䜕800䜕°C䜕焙烧后的催化剂表现出较好的脱硫活性,䜕而䜕400䜕°C䜕焙烧的催化剂脱硫活性最差.䜕䜕这说明䜕Ni䜕在催化剂上的不同化学形态是造成脱硫效果差异的主要原因,䜕而䜕NiO䜕是䜕Ni/AC䜕催化剂脱硫的主要活性物相.

The chemical state of Ni on activated carbon (AC) is different after calcination at different temperatures and can influence the desulfurization performance. NiO on AC is the best active species.Figure optionsDownload as PowerPoint slide