Industrial naphthalene contains thionaphthene, quinoline, and their derivatives, which can cause catalyst poisoning during the hydrogenation process, significantly reducing catalyst lifespan. A two-step hydrogenation technology involving fixed-bed hydrofining and deep hydrogenation of industrial naphthalene was designed to produce decalin. The hydrofining process mainly removed sulfur and nitrogen impurities from industrial naphthalene. Using NiMo sulfide catalysts for hydrofining, sulfur content was reduced from 3 200ppm to below 34ppm, and nitrogen content from 102ppm to below 38ppm. Taking the hydrofining product as the raw material for deep hydrogenation, a Pt-Pd/SiO2-Al2O3 catalyst was used in deep hydrogenation process and then both naphthalene and tetraline were completely converted to decalin, with the trans-decalin content in the product stabilized at approximately 87.2% and a maximum trans-/cis- of 6.8. Both catalysts exhibited excellent stability over a 1 000-hour test, showing no signs of deactivation.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |