Promoting asphaltene conversion by tetralin for hydrocracking of petroleum pitch

Tire pyrolysis char: Processes, properties, upgrading and applications

Direct primary brown coal liquefaction via non-catalytic and catalytic co-processing with model, waste and petroleum-derived hydrogen donors

A petroleum aromatic-rich component was used to prepare mesophase pitch by thermal condensation. In-process hydrogenation method was employed to achieve the hydrogenation reaction of intermediates generated during the thermal reaction using tetrahydronaphthalene (THN) as a hydrogen donor. Impacts of in-process hydrogenation on the properties of intermediates and mesophase pitches were investigated. It was found that the in-process hydrogenation was conducive to the generation of hydrogenated intermediates with concentrated extracted component distribution, uniform molecular structure and abundant naphthenic structures. The characterizations of mesophase pitches showed that the in-process hydrogenation contributed to the preparation of mesophase pitch with concentrated extracted component distribution, low softening point, large domain structure and ordered crystal structure. This was due to the increasing contents of naphthenic structures in intermediates. Moreover, the increase of methylene bridges in the product was the critical reason for improving the product's properties.

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Preparation and characterization of petroleum-based mesophase pitch by thermal condensation with in-process hydrogenation

Coal and waste direct liquefaction, using glycerol, polyethylene waste and waste tyres pyrolysis oil. Optimisation of liquids yield by response surface methodology

Demand for high-value petroleum products is increasing and crude oils and their distillation products are becoming heavier. The thermal cracking of a vacuum residue (VR) from REB (Russian Export Blend) crude oil was carried out in an autoclave. LCO (light cycle oil), naphtha, and brown coal (BC) were added with the aim of studying their effect on the final products composition. The elemental analysis (%C, %N, %H, %S) was performed and dynamic viscosity, density, GC of gases (“Refinery Gas Analysis”), solubility in hexane and toluene, and simulated distillation were examined in raw materials, gaseous, and liquid products. As anticipated, due to its high aromatics content, the addition of LCO proved the best option, obtaining the highest yield of lighter liquids. The naphtha addition resulted in a slight increment of heavier products in the gaseous phase and higher yields to solids. The literature does not contain any extensive studies of the addition of BC to VR in the hydrovisbreaking process. The addition of BC resulted in an increment in the yield of the gaseous product and assumed the highest relative total consumption of hydrogen during the reaction.

Hydrovisbreaking of vacuum residue from Russian Export Blend: influence of brown coal, light cycle oil, or naphtha addition

Most of the resources used for energy have a fossil origin and they are non-renewable materials. Using mixtures of waste materials with the currently used non-renewable materials can improve the renewability of the energy production. The goal of this work was to explore the effect of waste tire addition on a hydrovisbreaking process at low temperature. Four tests were carried out at 300 °C in H2 with different feedstocks: (1) vacuum residue; (2) tires; (3) 37.5wt% tires + 62.5wt% vacuum residue; (4) 15wt% tires + 85wt% vacuum residue. Dynamic viscosity, simulated distillation, density, elemental analysis (C, H, N, S% content) by ICP and analysis of gaseous products by GC–MS were carried out for all products. Content of insoluble compounds in hexane was estimated for the products from test (1) and vacuum residue. TGA analyses of the tires were carried out. The addition of tires to the vacuum residue brought a positive effect to increasing the yield of lighter products in the final liquid product. Densities and composition determinated by elemental analyses were similar for feedstock and products. The dynamic viscosity (60 °C) decreased from 24,550 to 17,700 mPa s for test (1) and to 1640 mPa s for test (3).

Jana Hamerníková

Papers

Hydrovisbreaking of vacuum residue from Russian Export Blend: influence of brown coal, light cycle oil, or naphtha addition

Effect of waste tires addition on a low-temperature hydrovisbreaking process of vacuum residue