Study on In Situ Catalytic Cracking of Coal Tar by Plasma Preparation of the Pyrolysis Coke Catalyst

Abstract

A two-stage pyrolysis fixed bed was used, and the vapor-modified pyrolysis coke was used as a carrier. A ZHPC catalyst was prepared by plasma calcination. Gas-phase tar produced by the pyrolysis of raw coal was subjected to in situ catalytic cracking to improve tar and gas yield. The effects of plasma calcination power, calcination time, and ZnO loading on in situ cracked products were studied. The prepared catalyst was characterized by X-ray electron spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, and scanning electron microscopy. The results showed that (1) compared with traditional catalysts, the catalyst prepared by plasma has better performance; (2) the optimal calcination time of the ZHPC catalyst is 5 min, calcination power is 60 W, and ZnO loading is 10%; (3) compared with raw coal pyrolysis, the optimal ZHPC catalyst on in situ catalytic cracking tar, gas yield increased by 66.16%; the cracking rate of tar increased by 54.46%, and the content of light components increased to 60.7%; (4) in situ catalytic cracking of tar with the optimal PC, the light tar has been greatly improved, in which the light oil, phenol oil, naphthalene oil, and wash oil have increased by 93.04, 126.31, 257.28, and 108.08%, respectively. The anthracene oil and asphalt have decreased by 26.98 and 58.71%; the tar cracking rate has increased.

Towards full recyclability of end-of-life tires: Challenges and opportunities

“…As discussed in the previous sections, vulcanized cis-rubbers are highly prone to secondary and tertiary reactions, including Diels-Alder reactions. In such cases, by increasing the heating rate and reducing the residence time, the possibility of secondary and tertiary reactions is minimized in order to decrease the production of tar, coke, and polar aromatics (Lei et al, 2020). The first step to reducing the residence time in the reactor and increasing the heating rate should be taken in the feeding section.…”

“…The first step to reducing the residence time in the reactor and increasing the heating rate should be taken in the feeding section. A twin-screw extruder at high temperatures of around 300 • C and/or crumb tire dissolution can result in complete devulcanization under optimal conditions (Lei et al, 2020). Released chains have lower thermal stability during pyrolysis, and the residence time can be decreased by half than vulcanized chains in similar conditions (Kebritchi et al, 2013).…”

Study on Denitration Performance of Solid Waste Blast Furnace Slag Catalysts under Different Preparation Processes

“… 40 , 41 At present, few studies focus on the application of blast furnace slag to denitration. 42 , 43 Therefore, selecting a suitable blast furnace slag catalyst preparation method for subsequent research is important.…”