Scrap Tires Pyrolysis Oil Research Articles

Production of transportation fuels via hydrotreating of scrap tires pyrolysis oil

The hydrotreating of scrap tires pyrolysis oil over commercial Ni-Mo/Al2O3 catalyst was researched for the best processing scheme allowing the production of high-quality alternative transportation fuels components of gasoline, jet, diesel, and marine fuel. Despite the initial high content of olefins, aromatics, sulfur, and nitrogen in pyrolysis oil, fuel components obtained by redistillation after the hydrotreating at 360 °C and 10 MPa met the majority of standard fuel specifications. Although the octane number of the naphtha fraction was lower, this fraction can be used as acomponent of the gasoline pool directly or after the catalytic reforming. Kerosene fraction can be utilized as jet fuel after the additional mild hydrotreatment or blending with hydroprocessed esters and fatty acids (HEFA) to decrease aromatics content. Diesel fraction can be blended with hydrotreated vegetable oils (HVO) to fulfill the density and cetane index specification. The bottom residue can be utilized as a low-sulfur fuel oil component in marine transportation.

Production of Transportation Fuels Via Hydrotreating of Scrap Tires Pyrolysis Oil

Production of Transportation Fuels Via Hydrotreating of Scrap Tires Pyrolysis Oil

Production and characterization of diesel-like fuel by catalytic upgrading of scrap tire pyrolysis oil using basic catalyst derived from blood cockle shell (Anadara Granosa)

This paper investigates the catalytic upgrading process in overcoming the scrap tire pyrolysis oil (STPO) complexities using a calcium-based catalyst derived from blood cockle shell (Anadara granosa). The calcined blood cockle (CBC) shells were synthesized by varying the temperature of calcination to 800, 900 and 1000 °C. In order to investigate the physico-chemical properties, the STPO was subjected to test method according to ASTM D975. The final distilled oil obtained from catalytic upgrading underwent gas chromatography with mass spectroscopy (GC–MS) analysis, in order to identify its chemical composition. According to the results, CaO material gives the lowest sulphur content (0.08%), compared to Ca(OH)2 and Na2CO3 catalysts. Among the CBC materials, the highest distilled oil yield is the CBC-1000 catalyst, with a value of 37.7%. The GC–MS analysis of distilled oil obtained from catalytic upgrading using the CBC-1000 catalyst reveals that, predominantly, the hydrocarbon chain is between C8 to C10, which is similar to conventional diesel fuel. The results also infer that there is improvement in STPO in terms of sulphur content (%), yield, and chemical compositions via the catalytic upgrading process. In conclusion, the CBC catalyst derived from blood cockle shell revealed that it has potential in upgrading the STPO to diesel-like fuel.

Lessening coke formation and boosting gasoline yield by incorporating scrap tire pyrolysis oil in the cracking conditions of an FCC unit

We have studied the effect of adding scrap tire pyrolysis oil (STPO) as feed or co-feed in the cracking of vacuum gasoil (VGO) using a commercial equilibrated catalyst. The cracking experiments were performed in a laboratory scale fluid catalytic cracking (FCC) simulator using VGO, STPO, or a blend of the two (20 wt% of STPO), contact time = 6 s, catalyst/feed ratio = 5, and 530 °C. The composition of the different feeds has been correlated with the yield of products and the amount-location-nature of the deactivating species (coke). Our results indicate that adding STPO increases proportionally the gasoline yield, synergistically increase the yield of light cycle oil while uncooperatively decrease the yields of heavy cycle oil and coke. We further investigated the effect on coke formation, characterizing deeply the coked catalyst and coke. In fact, the coke deposited under the cracking of STPO is more aliphatic, lighter, and located in the micropores of the catalyst. The complete analysis of the coke fractions (soluble and insoluble) have lighted the peculiar chemistry of these species as a function of the type of feed used. The results point to a viable and economically attractive valorization route for discarded tires.

Scrap tires pyrolysis oil as a co-feeding stream on the catalytic cracking of vacuum gasoil under fluid catalytic cracking conditions

The co-feeding of scrap tires pyrolysis oil (STPO) on the catalytic cracking of vacuum gasoil (VGO) has been investigated with the aim of exploring the capacity of the refinery fluid catalytic cracking (FCC) unit to upgrade discarded tires at large-scale. The runs have been carried out in a CREC (Chemical Reactor Engineering Centre) riser simulator reactor that mimics the behavior of the industrial unit at the following conditions: 500–560 °C; catalyst/oil ratio, 3–7 gcat goil−1; contact time, 6 s. Obtained results with the blend of 20 wt% STPO in VGO have been compared with those obtained in the cracking of the pure streams, i.e., STPO and VGO, to get a proper idea of the synergetic effects that could be involved in the co-feeding. This way, when the STPO is co-fed with the VGO the production of naphtha (C5–C12) and light cycle oil (C13–C20) lumps are maximized, as the over-cracking reactions that convert them into gaseous products (C1–C4) are mitigated. Consequently, the co-feeding promotes the production of high-interest hydrocarbons for refineries. Additionally, the naphtha obtained in the cracking of the blend shows a lower content of paraffins and naphthenes than that obtained with the VGO, and higher of olefins and aromatics.

Cracking of Scrap Tires Pyrolysis Oil in a Fluidized Bed Reactor under Catalytic Cracking Unit Conditions. Effects of Operating Conditions

Tire valorization by catalytic cracking of scrap tires pyrolysis oil has been investigated in a riser simulator reactor under fluid catalytic cracking (FCC) unit conditions using an equilibrated FC...

Production of Non-Conventional Fuels by Catalytic Cracking of Scrap Tires Pyrolysis Oil

Different commercial equilibrium fluidized catalytic cracking (FCC) catalysts have been tested in the upgrading of scrap tires pyrolysis oil (STPO) with the aim of obtaining automotive-like fuels. ...

A Data-Driven Reaction Network for the Fluid Catalytic Cracking of Waste Feeds

Establishing a reaction network is of uttermost importance in complex catalytic processes such as fluid catalytic cracking (FCC). This step is the seed for a faithful reactor modeling and the subsequent catalyst re-design, process optimization or prediction. In this work, a dataset of 104 uncorrelated experiments, with 64 variables, was obtained in an FCC simulator using six types of feedstock (vacuum gasoil, polyethylene pyrolysis waxes, scrap tire pyrolysis oil, dissolved polyethylene and blends of the previous), 36 possible sets of conditions (varying contact time, temperature and catalyst/oil ratio) and three industrial catalysts. Principal component analysis (PCA) was applied over the dataset, showing that the main components are associated with feed composition (27.41% variance), operational conditions (19.09%) and catalyst properties (12.72%). The variables of each component were correlated with the indexes and yields of the products: conversion, octane number, aromatics, olefins (propylene) or coke, among others. Then, a data-driven reaction network was proposed for the cracking of waste feeds based on the previously obtained correlations.

Characterization and controlled combustion of carbonaceous deactivating species deposited on an activated carbon-based catalyst

The composition of the carbonaceous deactivating species (coke) deposited on a Pt and Pd supported P-containing activated carbon catalyst has been studied. These deactivating species were deposited on the catalyst during the hydrocracking of scrap tire pyrolysis oil at 400–500°C, and it has been selectively characterized by means of temperature-programmed oxidation (TPO), temperature-programmed desorption/gas chromatography (TPD/GC) and laser desorption-ionization/mass spectroscopy (LDI/MS). In addition, the evolution of the textural properties and the acidity of the deactivated catalysts have been evaluated. The high thermal and oxidation resistance of the catalytic support has allowed to combust the coke in the TPO and calculate its intrinsic activation energy as a function of the extent of the combustion. Combined TPO and LDI/MS results have shown that an increase in the hydrocracking temperature attenuates the catalyst deactivation due to the hydrocracking of coke precursors. Coke aging, by evolving towards a more condensed structure, is also favored at higher hydrocracking temperatures. The combustion of the most condensed coke requires of higher temperatures than 375°C, which hinders the complete regeneration of the activated carbon-based catalyst.

Kinetic Modeling of the Hydrotreating and Hydrocracking Stages for Upgrading Scrap Tires Pyrolysis Oil (STPO) toward High-Quality Fuels

The upgrading of scrap tires pyrolysis oil (STPO) has been studied in order to produce high-quality alternative fuels, conceived as the second and third stage of an industrially orientated valorization pathway for tires: pyrolysis, hydrotreating, and hydrocracking. The experiments have been carried out in a fixed-bed reactor under the following experimental conditions: (i) for hydrotreating: NiMo/Al2O3 catalyst; time on stream (TOS), 0–8 h; 300–375 °C; 65 bar; H2:oil ratio, 1000 (v/v); space time, 0–0.5 gcat h gfeed–1; and (ii) for hydrocracking: PtPd/SiO2–Al2O3 catalyst; TOS, 0–6 h; 440–500 °C; 65 bar; space time, 0–0.28 gcat h gfeed–1; H2:oil ratio, 1000 (v/v). From the results, lump-based kinetic models have been established for both stages, considering the reactions of (i) hydrodesulfurization (HDS), (ii) hydrocracking (HC), and (iii) hydrodearomatization (HDA) in each one of them. Catalyst deactivation is insignificant in the hydrotreating stage but important for the hydrocracking stage. Therefore, d...

Prospects for Obtaining High Quality Fuels from the Hydrocracking of a Hydrotreated Scrap Tires Pyrolysis Oil

The hydrocracking of hydrotreated scrap tires pyrolysis oil (HT-STPO) has been studied aiming at high-quality refinery blends for alternative automotive fuels. The hydrocracking runs have been carried out with a PtPd/SiO2-Al2O3 catalyst in a fixed-bed reactor at 440–500 °C, 65 bar and space time of 0.16 h. The catalyst has been characterized by inductively coupled plasma optical emission spectroscopy, N2 adsorption–desorption isotherms, and tert-butylamine adsorption–desorption (TPD), while coke has been studied both quantitatively and qualitatively by thermogravimetric-temperature-programmed oxidation (TG-TPO), Fourier transform infrared-TPO, and Raman spectroscopy. During the first two hours of reaction and at temperatures above 480 °C, we have been able to (1) reach ultra low sulfur levels lower than 15 ppm; (2) remove almost completely the less interesting fraction—boiling points higher than 350 °C, named as the gasoil fraction—with remaining amounts lower than 1 wt %; (3) obtain a paraffinic and isop...

Upgrading model compounds and Scrap Tires Pyrolysis Oil (STPO) on hydrotreating NiMo catalysts with tailored supports

The upgrading of Scrap Tire Pyrolysis Oil (STPO) has been studied in order to remove undesired sulfur, nitrogen and unsaturated compounds while improving the properties of its different fractions (naphtha, diesel and gasoil) toward being used as a potential blend in the refinery. The studied catalysts are NiMo supported on 5 porous materials: γ-Al2O3 (ALM catalyst), SiO2–Al2O3 (ASA), SBA-15 (SBA), MCM-41 (MCM) and an equilibrated FCC catalyst (FCC). The hydrotreating runs have been carried out in a fixed bed reactor at 275–375°C and 65bar. The catalysts were characterized by ICP-AES, N2 adsorption–desorption isotherms, H2 chemisorption, XRD, XPS, TPR and terc-butylamine adsorption–desorption (TPD). A preliminary catalyst screening with a model mixture of representative STPO compounds has been performed for selecting the most active catalysts: ALM, ASA and MCM catalysts ensured the 99.9% removal of sulfur. Secondly and in the hydrotreating of STPO, our results point the suitability of ASA catalyst for obtaining the highest proportion of naphtha (25wt%) and diesel (57wt%), ALM catalyst for increasing the yield of paraffins and the cetane number in diesel, and the promising performance of MCM catalyst for facilitating internal mass transfer.