排序方式: 共有4条查询结果,搜索用时 15 毫秒
1
1.
2.
采用四槽高压连续流动反应器研究了添加助剂Ba、K和Sm对活性炭负载钴催化剂氨合成活性的影响,结果发现,添加助剂Ba、K和Sm可以提高催化剂的氨合成活性,其中,Ba的促进效果最好,Ba与Co物质的量比为0.3时,催化活性最高。在Ba-Co/AC催化剂中,助剂Sm的加入降低了催化剂的氨合成活性,而少量K助剂(K与Co物质的量比为0.25~0.5)可以提高其催化性能,在10 MPa、10 000 h-1和450 ℃条件下,双助剂催化剂的氨合成活性可达120 mmol·(g·h)-1,进一步增加K的量,其氨合成活性下降。 相似文献
3.
研究了浸渍条件和还原剂种类对蒽醌氢化制备过氧化氢Pd-BaO/δ,θ-Al2O3催化剂性能的影响。结果表明,当浸渍液温度60 ℃和pH=3.5时,催化剂上钯金属的分散度较高,钯粒子较小,催化剂活性较高。使用不同还原剂也会影响催化剂的Pd分散度和粒子大小,其中,以水合肼和H2还原得到的催化剂有较高的活性比表面积、分散度和较小的粒子尺寸,而经硼氢化钾还原的催化剂的分散度偏低。水合肼还原得到的催化剂的活性较高,H2还原的催化剂活性次之,以硼氢化钾还原的催化剂活性最差。 相似文献
4.
Rare earth gangue, which mainly consists of mixtures of light rare earths such as lanthana, ceria, neodymium oxide and praseodymium oxide, was used as the promoter of fused iron catalysts for ammonia synthesis. The result showed that the activity of the catalyst promoted with rare earth gangue was comparable with those of commercial iron catalysts with high amount of cobalt. The role of rare earths was owed to their advantages for favoring the deep reduction of the main composite in catalyst, i.e., iron oxide. This fmding indicated that the use of rare earth gangue could decrease the content of cobalt or even completely replace cobalt, which was used to be regarded as unsub- stitutable promoters for high performance ammonia catalyst; therefore, the cost of fused iron catalysts would decrease significantly. 相似文献
1