Petroleum Coke Research Articles

Steam co-gasification characteristics of black liquor char and petroleum coke coupled with TiO2 direct causticization

The isothermal steam gasification experiments of a ternary mixture (BTP) containing black liquor char (BLC), causticizing agent (TiO2) and petroleum coke (PC) were carried out at 850 °C based on a thermogravimetric analyzer (TGA) and a horizontal fixed-bed reactor. A co-gasification process of BLC and PC coupled with TiO2 direct causticization was explored from the aspect of reaction rate as well as the characteristics of gaseous products and gasification residues (GR). The results show that in comparison to the weighted average (BTPtheo) of the independent gasification of TiO2 direct causticized BLC and PC, significant synergistic effects could be aroused during the coupled co-gasification process due to promoting action of mNa2O·nTiO2 on gasification of organic carbon. Specifically, the maximum reaction rate of BTP reaches 7.0%/min, which is 2.9 times that of BTPtheo. The content and yield of effective gas components, i.e., H2+CO, in the gas products, as well as its lower heating value (LHV) of BTP are 81.1%, 2059 mL/g, and 9343 kJ/m3, respectively, which is 6.8%, 137.3%, and 5.5% higher than that of BTPtheo. The carbon conversion and energy output ratio of BTP reaches 95.0% and 1.13, respectively, which is increased by 61.6% and 135.4% relative to the theoretical superposition value. In addition, the relative loss of inorganic salts in BTP during the whole thermochemical conversion process is effectively controlled at a lower level of about 9.4%. Since the Na-containing salts in GR of BTP are mainly mNa2O·nTiO2 with higher thermal stability, and GR maintains good particle flowability, it is conducive to downstream alkali recovery.

Co-pyrolysis of petroleum coke and wood pellet blend: Kinetic and Thermodynamic Evaluation using Thermogravimetric Analysis

The increasing demand for sustainable energy attracted researchers to explore the co-pyrolysis of several wastes. The present study evaluated the kinetic and thermodynamic parameters for the co-pyrolysis of wood pellets and petroleum coke (1:1 by mass) blends using thermogravimetric analysis. The TGA data were analyzed through iso-conversional Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS) models, along with the Coats-Redfern method. The results reflect that the order of reaction increases with an increased heating rate. An average value of activation energy calculated was 119.6 kJ mol−1 (OFW) and 126.2 kJ mol−1 (KAS). The values calculated for ΔH, ΔG and ΔS were in line with the past relevant studies on blends. The value ΔG was observed to fall around 182 kJ mol−1. The Coats-Redfern reaction mechanism indicates that D5 (based on diffusion) and F3 (based on chemical reaction) are best apt to the thermal process of degradation. DTA data specifies that degradation involves exothermic and endothermic reactions for the temperature range under study. The study not only provide the basic characteristics of one of the most dominant waste from refinery, but provides a platform for its futuristic potential usage with reliable kinetic and thermodynamic parameters for scale up, optimization, utilization and limitation for efficient system design.

Разработка методов получения углеродных адсорбентов на основе Ангренского угля и нефтяных остатков

Currently, activated carbon adsorbents are widely used in the world for industrial wastewater treatment from various organic compounds, sorption of heavy metal ions and life-threatening radioactive substances. Carbon adsorbents with hydrophobic properties are mainly modified based on the brown coal, coke, scape, and bark of plants. The methods of manufacturing coal adsorbents based on Angren coal, petroleum coke and asphaltenes are listed. The physicochemical composition and complete thermodynamic properties of the activated carbon adsorbent were studied. It was found that during the heat treatment of mixtures of carbonaceous raw materials, its mass is lost with increasing temperature. At the same time, the adsorption activity of iodine increases with increasing temperature. Depending on the change in temperature of the obtained carbon adsorbent samples, the calculated surface area with respect to iodine is 280.7 m2/g with a weight loss of 0.2 g. The differential heat of adsorption, isotherm, molar entropy and thermokinetics of the benzene and toluene molecules studied in the article are calculated. The adsorption of 4.5 mmol/g of benzene and 3.5 mmol/g of toluene on the activated carbon adsorbent was determined. It is noted that during the adsorption of benzene and toluene by the obtained adsorbent from activated carbon, the differential heat of reaction gradually decreases. When recalculating the isothermal adsorption of benzene and toluene on activated carbon according to the equation of the volumetric theory of micropore saturation, it was obtained that 84.5 % of benzene and 94.2 % of toluene were adsorbed on the pores of the adsorbent.

Screening activated carbons produced from recycled petroleum coke for acid gas separation

Screening activated carbons produced from recycled petroleum coke for acid gas separation

Hydrodesulphurisation of Petroleum Coke

Hydrodesulphurisation in a fluidized bed offers the most attractive process for the desulphurisation of petroleum coke. Results of coke hydrodesulphurisation clearly indicate that the rate of sulphur removal is greatest at about 1100 K. The hydrodesulphurisation process is particularly effective with cokes of high sulphur content and high ash and heavy metals content, as at temperatures less than 1100 K the adverse effects of high ash and heavy metals content on desulphurisation is largely avoided. The process leads in general to increased porosity, density and surface area and improved reactivity. These properties are dependent on the sulphur concentration. The greater the amount of sulphur removed, the greater the structural changes expected in the coke treated. The weight loss is less than 10%.

Coal-based sulfur hybrid sorbent for removal of Hg0 from flue gas. Part 2. High organic sulfur coal

It is a win–win strategy to prepare mercury sorbents from low-cost high-sulfur raw materials. In part 1, mercury sorbents with excellent performance were prepared from high inorganic sulfur coal through KOH activation. However, this method does not work for high organic sulfur coal. In this work, a two-step preparation method is developed to prepare mercury sorbents from high organic sulfur coal. The first step is the co-pyrolysis/carbonization of Fe2O3 and coal, during which organic sulfur in coal is converted into FeSx. XPS shows that the percentage of Sx2–/S on the surface of the carbonized samples gradually increases from 5.4% to 22.2% with the m(Fe):m(So) ratio from 0:4 to 5:4. The second step is KOH activation, and it converts FeSx into various S species, including C-S, S0, S22− and S2−. Among the prepared mercury sorbents, LF+3Fe/4S-A (m(Fe):m(So) = 3:4) shows the best mercury removal performance, and its mercury removal efficiency remains above 84% for 120 min under N2+O2 at 120 °C. The Hg-TPDD and XPS results indicate that S*, including C-S, S0 and S22−, are the major active sites for mercury removal rather than Fe element, and HgS is the main existing form of mercury on the used sorbents. Besides LF coal, this two-step process is also applicable to other high organic sulfur coals (such as LL coal, WJZ coal, and SY coal) and high-sulfur petroleum coke.

A stepwise regression to identify relevant variables affecting the environmental impacts of clinker production

The construction sector contributes to 8% of carbon dioxide emissions, most of them caused by clinker production: in recent years, the efforts to reduce environmental impacts are growing. This paper investigates the environmental performances of clinker production and the factors driving emissions. For this purpose, the environmental impacts of 41 different grey clinkers produced in Italy from 2016 to 2021 certified by a third party according to the European standard EN 15804 have been assessed. Three input datasets (i.e., energy consumption, raw materials, and transport) have been investigated to identify the most significant variables that affected the environmental impact categories in the period 2016–2020: a stepwise regression allowed the identification of the optimal predictors to be included in the multiple regression models. The most significant variables are pet coke, fossil fuels, natural raw materials, and lorry transport. The identified models have been validated having regard to 2021 data. Therefore, for each impact category, multiple positive and negative dependencies which bear an effect on the environmental results have been quantified. The output provides proven quantitative results that can support cement producers to develop low-impacting clinker recipes.

Preparation of mesophase pitch with domain textures by molecular regulation of ethylene tar pitch for boosting the performance of its carbon materials

The fast formation of mosaic optical textures is one of main factors limited its application in high performance carbon materials due to active components containing olefins in ethylene tar pitch (ETP). In this paper, a thermal pretreatment process is proposed for effective molecular reformation of ETP, especially for separation of these active components containing olefins. Mesophase pitch with developed rheological properties and domain anisotropic textures was then prepared via polymerization of the post-treated ETP. Molecular structures analysis results show that these active components containing olefins in ETP prefer to form macromolecules consisted of multiple aromatic cores via rapid radical reactions, and develop a mixed anisotropic texture consequently. Nevertheless, these normal aromatic components tend to produce a semi-rigid molecular structure with less aromatic cores by aliphatic chains transfer reactions and stable radical polymerization reactions. This architecture facilitates its molecular stacking and orientation thus the prepared mesophase pitch (ETP-MP) shows better anisotropic domain texture. The prepared mesophase pitch had suitable performance for the application in needle cokes and carbon foams. This work will help to expand the manufacturing of ETP-derived carbon materials through molecular reformation.

One-pot synthesis of self S-doped porous carbon for efficient CO2 adsorption

Considering the rising environmental and efficiency concerns, the development of porous carbon via a surface decoration approach has received great attention for selectively adsorb CO2 from the flue gas. Herein, self-S-doped porous carbon was prepared from petroleum coke with high sulfur content (PHS) utilizing KOH as an activating agent. The effect of the activating temperatures and the KOH/PHS mass ratio on the physical feature and CO2 uptake performance of the as-synthesis porous carbons was fully examined. The optimal sample (PHS-650-3) presents the specific BET surface area and total pore volume of 1278 m2/g and 0.56 cm3/g, respectively. The PHS-650-3 sample displayed the maximum CO2 adsorption capacity of 4.18 and 5.57 mmol g−1 at 25 and 0 °C and 1 bar thanks to its enhanced textural characteristics and high amount of sulfur functionality on the surface. Last but not least, the as-synthesized S-doped porous carbon shows ideal adsorption solution theory (IAST) CO2/N2 selectivity of 21, fast adsorption kinetics, suitable heat of adsorption value and stable uptake capacity upon consecutive adsorption cycles, claiming its readily potential CO2 adsorption applications.

One-pot synthesis of N-doped petroleum coke-based microporous carbon for high-performance CO2 adsorption and supercapacitors

Waste resource utilization of petroleum coke is crucial for achieving global carbon emission reduction. Herein, a series of N-doped microporous carbons were fabricated from petroleum coke using a one-pot synthesis method. The as-prepared samples had a large specific surface area (up to 2512 m2/g), a moderate-high N content (up to 4.82 at.%), and high population (55%) of ultra-micropores (<0.7 nm). Regulating the N content and ultra-microporosity led to efficient CO2 adsorption and separation. At ambient pressure, the optimal N-doped petroleum coke-based microporous carbon exhibited the highest CO2 uptake of 4.25 mmol/g at 25°C and 6.57 mmol/g at 0°C. These values are comparable or even better than those of numerous previously reported adsorbents prepared by multistep synthesis, primarily due to the existence of ultra-micropores. The sample exhibited excellent CO2/N2 selectivity at 25°C owing to the abundant basic pyridinic and pyrrolic N species; and showed superior CO2 adsorption-desorption cycling performance, which was maintained at 97% after 10 cycles at 25°C. Moreover, petroleum coke-based microporous carbon, with a considerably high specific surface area and hierarchical pore structure, exhibited excellent electrochemical performance over the N-doped sample, maintaining a favorable specific capacitance of 233.25 F/g at 0.5 A/g in 6 mol/L KOH aqueous electrolyte. This study provides insight into the influence of N-doping on the porous properties of petroleum coke-based carbon. Furthermore, the as-prepared carbons were found to be promising adsorbents for CO2 adsorption, CO2/N2 separation and electrochemical application.

Growth responses of 20 boreal forest species to oil sands non‐segregating tailings: significance for reclamation

Oil sands mining in northeastern Alberta, Canada, generates tailings containing sand, silt, clay, water, and residual bitumen with hydrocarbons. The impact of tailings on revegetation is a major environmental concern and poses a significant land reclamation challenge. Oil sands companies have recently developed technologies that use thickeners in combination with carbon dioxide to produce non‐segregating tailings (NST), to accelerate the consolidation of tailings while sequestering greenhouse gases. Effects of these tailings on plant re‐establishment have yet to be determined. We investigated the impact of NST on biomass and physiology of 20 boreal woody plant species grown in environmentally controlled growth rooms. The seedlings were grown for 8 weeks in NST capped with boreal forest topsoil or peat‐mineral soil mix or petroleum coke in 50‐cm‐long polyvinyl chloride pipes. We found that the biomass of balsam fir, beaked hazelnut, blueberry, green alder, Labrador tea, lowbush cranberry, paper birch, and raspberry was severely reduced by NST, while the effects on balsam poplar, Bebb's willow, chokecherry, dogwood, saskatoon, and white spruce were relatively weak. This was also the case for jack pine, which showed poor survival in NST. The negative impact of NST on plants can be largely explained by elevated sodium and decreased foliar nutrient concentrations. The impact of NST capping with petroleum coke on plant growth was non‐significant. Differences among species in their survival and biomass responses to NST appeared to be partly a reflection of their natural habitats. Findings from this study can help guide revegetation oil sands reclamation strategies.

Increasing biodegradability of a real amine-contaminated spent caustic problematic stream through WAO and CWAO oxidation using a high specific surface catalyst from petcoke

Different operating conditions of wet air oxidation and catalytic wet air oxidation have been studied for the treatment of highly concentrated methyldiethanolamine wastewater streams from amine units of acid gas recovery in petrol refineries. These units occasionally generate streams of high methyldiethanolamine content that require special actions to avoid undesirable impacts on the downstream biological process of the petrochemical wastewater treatment plant due to its inhibition effect. The wet air oxidation treatment achieved remarkable removals of methyldiethanolamine, sulfides, chemical oxygen demand and total organic carbon (99%, 95%, 65% and 38%, respectively). Likewise, activated petroleum coke materials from the own refinery plant were tested as catalysts in the process. These materials were prepared under different conditions (chemical activating agent and thermal carbonization process). The catalytic wet air oxidation treatment using an activated petroleum coke was able to remove the methyldiethanolamine at milder operation conditions keeping a similar performance in terms of wastewater treatment removals as compared to the non-catalytic experiments. This technology significantly increased the biodegradability of the treated effluents ranging from 25 to 70 % due to the formation of more biodegradable substrates (acetic acid and ammonium) for further biological treatment.

Transforming micropores to mesopores by heat cycling KOH activated petcoke for improved kinetics of adsorption of naphthenic acids

Formation of activated carbon from petroleum coke by KOH, results in high specific surface area materials that are predominantly microporous. This initial microporosity means that the adsorption kinetics of target species are not as rapid as they could be, thus limiting environmental remediation applications for the material. To address this problem a series of additional heat cycles with no additional chemical inputs were applied after activation but prior to the removal of activating agents. This process resulted in the oxidation of residual potassium metal from the initial activation which allows it to function again as an activating agent for the subsequent cycles. The heat cycling resulted in an increase in mesoporosity by 10–25% with each successive cycle independent of the KOH to feedstock ratio. This was shown to be demonstrably different than equivalently extended heating times, thus identifying the importance of thermal cycling. Adsorption kinetics of three model naphthenic acids showed faster kinetics for the pore widened activated carbon. The t1/2 times dropped from 20 to 6.6 min for diphenyl acetic acid, 34.3 to 4.5 min for cyclohexane acetic acid, and 51.4 to 12.0 min for heptanoic acid.

Effect of Current Density on Specific Characteristics of Negative Electrodes for Lithium-Ion Batteries Based on Heat-Treated Petroleum Coke

The results of comparative studies of the effect of current density on the average discharge voltage and specific discharge capacity of carbon electrodes based on heat-treated petroleum coke and graphite are presented. The carbon obtained by heat treatment of petroleum coke is shown to have better kinetic characteristics than graphite. The increase in the current density from 0.2 mA/cm2 (36 mA/g) to 2 mA/cm2 (364 mA/g) leads to a decrease in the discharge capacity of heat-treated petroleum coke by 26%; graphite, by 93%. When the current density is restored to 0.2 mA/cm2, the discharge capacity of carbon electrodes is also restored to its initial value. The increase in the current density is also shown to lead to increase in the average discharge voltage of lithium–carbon cells. Thus, with the increase in current density from 0.2 to 2 mA/cm2, the average discharge voltage of the lithium–carbon cells with the electrode active component of the heat-treated petroleum coke increased from 0.39 to 0.62 V; that of graphite, from 0.14 to 0.35 V.

Recycling Waste from Coal and Petroleum Coke Production

Recycling Waste from Coal and Petroleum Coke Production

Effect of Current Density on Specific Characteristics of Negative Electrodes for Lithium-Ion Batteries Based on Heat-Treated Petroleum Coke

Effect of Current Density on Specific Characteristics of Negative Electrodes for Lithium-Ion Batteries Based on Heat-Treated Petroleum Coke

Multiregional input–output analysis of carbon transfer in interprovincial trade and sectoral strategies for mitigation: Case study of Shanxi province in China

Embodied carbon emissions have an important role in China's “dual carbon” target and carbon reduction policy. Our study applied a multiregional input–output (MRIO) model and structural decomposition analysis (SDA) to examine the spatiotemporal evolution and driving forces of embodied carbon emissions in the specific region of Shanxi Province, an energy-rich region in China, in the empirical study using MRIO data. First, we found that Shanxi had considerable net embodied carbon outflow in interprovincial trade, with outflow increasing from 216.18 Mt in 2012 to 221.60 Mt in 2017. Second, the main driving forces of embodied carbon outflow include technological level and trade demand. We then classified 29 sectors into six categories, including mainly developed, controlled, moderately guided, moderately controlled, cost guided, and maintained to describe the relationship between the net transfer of embodied carbon emissions and value added, and formulated proposed sectoral development policies. Third, the sectors with the highest net embodied carbon outflow include electricity and heat production and supply; metal smelting and rolling processing; and petroleum processing, coking, and nuclear fuel processing. We constructed a coupled relationship model to adjust the technology and scale of interprovincial trade to reduce carbon emissions with lower cost and higher equity. The results can be used as a reference for formulating carbon reduction policies in energy-rich regions.

Adsorption of single‐ring model naphthenic acid from oil sands tailings pond water using physically activated petroleum coke

AbstractPetroleum coke‐derived activated cokes were prepared and used for the adsorptive removal of a single‐ring naphthenic acid (NA) from synthetic oil sands process affected water (OSPW). CO2 activation produced carbon with a larger mesopore volume fraction (0.67) than steam activation (0.25). Interestingly, prolonging the activation time of CO2 from 6 to 9 h led to a simultaneous increase in specific surface area (276–405 m2/g) and mesopore volume (0.51–0.67). Furthermore, a positive relationship was found between the pseudo‐second‐order kinetic rate constant and the mesoporous volume of the activated coke. This suggests both the importance of pore size on kinetics and the fact that physical activation with a reagent such as CO2 may be better suited than chemical activation due to its ability to create mesopores. Although enlarging the pores and accelerating the adsorption rate, post‐oxidation had detrimental effects on adsorption capacity, resulting in a decrease in equilibrium adsorbed amount from 115 to 34 mg/g, a 70% decrease, when post‐oxidized with O2, due to the negative charge of oxygen‐containing functional groups. On the other hand, the measured adsorption capacity increased by over 60% when activated coke was treated with ammonia, a result of the positively charged nitrogen‐containing surface groups. Finally, in real OSPW, the activated coke had a much lower capacity for total acid‐extractable organics than for the model NA. Therefore, activated petroleum coke may not be the best choice for treating raw tailings pond water and may be better suited for polishing.

High-Purity Graphitic Carbon for Energy Storage: Sustainable Electrochemical Conversion from Petroleum Coke.

The petroleum coke (PC) has been widely used as raw materials for the preparation of electrodes in aluminium electrolysis and lithium-ion batteries (LIB), during which massive CO2 gases are produced. To meet global CO2 reduction, an environmentally friendly route for utilizing PC is highly required. Here, a simple, scalable, catalyst-free process that can directly convert high-sulfur PC into graphitic nanomaterials under cathodic polarization in molten CaCl2 -LiCl at mild temperatures is proposed. The energy consumption of the proposed process is calculated to be 3627.08 kWh t-1 , half that of the traditional graphitization process (≈7,825.21 kWh t-1 graphite). When applied as a negative electrode for LIBs, the as-converted graphite materials deliver a competitive specific capacity of ≈360 mAh g-1 (0.2 C) compared with commercial graphite. This approach has great potential to scale up for sustainably converting low-value PC into high-quality graphite for energy storage.

Resource Recovery from Crude Oil Sludge Using Solvent Extraction and Delayed Cooking Method

The main objective of this work is to make an economically useful recovery from waste. Crude oil sludge is gotten from the bottom of crude oil storage tank. 100mI (109.2g) of crude oil sludge when treated with 50mI, 100mI, 200mi……400 ml of solvent heptane resulted in the formation of three different layers. The first layer contains the solvent and some extracted crude oil in the oil phase. This is distilled to get different hydrocarbon fractions. The second layer is asphaltic residue which when furnace treated and activated or washed and neutralized with inclusion of additives yields activated coke used as adsorbent and newsprint paste respectively. The third layer is the mud or clay which could be furnace treated to produce activated clay.Results show that petroleum coke is best activated at 800°C and the optimal condition for bleaching red palm oil by the adsorbent is at 130•C.