Catalytic co-pyrolysis of oil sludge with HDPE to obtain paraffinic products over HUSY zeolites prepared by dealumination and desilication

Regulation of the Si/Al ratios and Al distributions of zeolites and their impact on properties

“…Recently, a series of high-silica Y zeolites have been prepared in the laboratory for cracking and pyrolysis. 24,61,100 Y zeolite with a Si/Al ratio of 8.0 exhibited higher conversion than two USY zeolites with Si/Al ratios of 5.3 and 6.9 in n-octane and 1,3,5triisopropylbenzene(TIPB) cracking. 24 Compared to the USY zeolite with lower Si/Al ratios, the USY zeolite with higher Si/Al ratios has fewer acid sites.…”

“…Thus, alkaline solution treatment of zeolites can remove the Si atoms from the framework, which certainly reduces the Si/Al ratios 142,143 and thus forms the mesopores within the zeolite crystals. 45,[144][145][146][147][148][149][150][151][152] Up to date, the inorganic bases of NaOH 45,100,111,142,[147][148][149][150][151][152][153][154][155] and Na 2 CO 3 145 have been used for the desilication of zeolites. For example, Bjørgen and co-workers produced ZSM-12 with the Si/Al ratios of 13-34 by treating the calcined ZSM-12 (Si/Al = 39) with 0.2 M-0.6 M NaOH solutions at temperatures of 35°C, 65°C, or 85 °C and duration from 15 to 60 min.…”

“…23 In the co-pyrolysis of oil sludge and high density polyethylene (HDPE) catalysed by the USY zeolites, Please do not adjust margins Please do not adjust margins Calderari and co-workers found that the catalytic cracking process followed a carbenium ion reaction mechanism, which was generated by the removal of a negative hydrogen ion from the alkanes or the protonation of olefins. 100,181 The species containing carbenium ions cracked to small hydrocarbons on the BASs and Lewis acid sites of USY zeolites and resulted in the formation of the new carbonium ions. 182,183 Recently, Shen and co-workers discovered that the dealuminated Beta zeolite generated more carbonium ions in the cracking of n-octane due to the enhanced strength of BASs, which is beneficial for hydrocarbon conversion.…”

Analysis of n-hexane, 1-hexene, cyclohexane and cyclohexene catalytic cracking over HZSM-5 zeolites: effects of molecular structure

“…Hydrocarbon catalytic cracking is a traditional topic that has been researched for almost a century. Detailed information about hydrocarbon behavior over zeolites is of significant importance to the production of light olefins, [1][2][3][4][5] the petroleum process, [6][7][8] solid waste resources, [9][10][11][12] etc.…”

Wax Separated Effectively from Fischer-Tropsch Wax Residue by Solvent Desorption: Thermodynamic and Kinetic Analysis

“…In many countries, FTWR is classified as hazardous waste. If improperly handled, it will produce toxic and hazardous substances [11,12], causing damage to the ecological environment and posing a threat to human health. Reports have reported that approximately 20,000 tons of slag wax are produced in China each year, 60% of the slag wax is incinerated, and the rest is used for landfill [13].…”