The purpose of this research is to evaluate, at a molecular level, the removal of nitrogen compounds from vacuum gas oil (VGO), which is used as feedstock for fluid catalytic cracking units. Here, a VGO sample was treated with two different adsorbents: an argillaceous material specifically developed for the removal of nitrogen compounds in middle distillate cuts (kerosene and diesel) and a commercial silica adsorbent. Breakthrough curves were built on two temperature levels (80 and 150 °C), containing different rupture times (from 60 to 420 min), to determine their influence on nitrogen compound removal. All samples, produced from each condition of adsorption, were analyzed by positive and negative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry [ESI(±)­FT-ICR MS]. Besides FT-ICR MS characterization, the total nitrogen content was monitored. FT-ICR MS indicated that the removal of nitrogen compounds by the clay adsorbent was enhanced when the temperature was higher (150 °C). Conversely, silica has shown a rich adsorption capacity at moderate temperatures (80 °C). This result corroborates the existence of two different adsorption mechanisms. The clay adsorption mechanism is likely a chemisorption process, while the silica adsorption mechanism is related to physisorption. Both processes displayed better performance in short rupture times, for example, at 60 min. Longer rupture times require a saturation of the adsorption process through a packed bed. FT-ICR mass spectra detected a wide range of compounds from m/z 220 to 800, with average molecular weight distributions (M w) that increase as a function of decreasing the total nitrogen content (424 → 711 Da). Class distribution showed a removal preferential of N­[H] and N2[H] compounds with low carbon numbers (

Stringent specifications for sulfur compounds content and the need to use oils with large amount of nitrogen compounds are challenges for fuel producers. Adsorption is an alternative process to remove sulfur and nitrogen compounds and clays are promising adsorbents for this removal. In this work, the adsorption performance of different commercial claysClay A (attapulgite), Clay B (bentonite), and Clay C (bentonite)for the removal of sulfur and nitrogen compounds from a real diesel stream was studied through kinetic and isothermal experiments. The bentonite clays showed the best adsorptive capacity for the removal of sulfur and nitrogen compounds, probably due to the presence of Brønsted acid sites. The highest adsorption capacity was observed for Clay B: 0.174 mol kg −1 for sulfur compounds and 0.127 mol kg −1 for nitrogen compounds. Clay A was more selective to the removal of nitrogen compounds. Equilibrium data showed that adsorbate−absorbate and adsorbate−surface interactions predominate for sulfur and nitrogen compounds, respectively, for Clay A and Clay B.

This study was designed to investigate the use of commercial adsorbent materials for the removal of nitrogen compounds from a vacuum gas oil obtained from an industrial atmospheric distillation unit. Two types of adsorbents were tested: a clay developed specifically for the removal of nitrogen compounds from middle distillates (jet fuel and diesel); and a silica used in a variety of industries. Kinetic and thermodynamic equilibrium experiments were conducted at three temperatures: 80, 100, and 120 °C. The variation in the concentration of nitrogen and aromatic compounds was monitored throughout the kinetic adsorption and thermodynamic equilibrium experiments. When an adsorbent/gas oil mass ratio of 0.75 was used, the clay removed around 70 % of the basic nitrogen compounds from the gas oil, while the silica removed 80 % of the same compounds, which are the ones that effectively hamper catalytic cracking. The silica also removed 14.2 % of the aromatic compounds, while the clay only removed 4.1 %. This study shows that it is possible to treat a viscous hydrocarbon feed using an adsorption process to remove nitrogen compounds without the need to dilute the feed. Using a fluidized bed advanced cracking evaluation (ACE) unit, which simulates a fluid catalytic cracking unit on a bench scale, the gas oil treated with silica produced 3 % more liquid petroleum gas (LPG) and 4 % more gasoline, while the gas oil treated with clay produced 2 % more LPG and 3 % more gasoline than the untreated gas oil.

Ultra-low sulfur diesel (ULSD) is obtained by Light Gas Oil (LGO) and Light Cycle Oil (LCO) feedstocks (middle fractions from distillate petroleum). In addition to the environmental requirements related to the production of fuels with a lower content of nitrogen, technical specifications refineries also stimulate the need to remove such compounds. Nitrogenous compounds, for example, are strong inhibitors for hydrodesulfurization reactions. As Brazilian oil has a high amount of nitrogen compounds, an alternative process for nitrogen removal has been investigated, such as adsorption. In this paper, the nitrogen removal was investigated. The adsorption tests were carried out in a shaking water batchs, by performing kinetic and isotherm tests. Two commercial clays were used: Fuller's earth and bentonite.

Currently, the biggest concern of different industries is the disposal of waste generated. The liquid effluents in general have more elaborate studies realizing alternatives for their treatment by reducing their toxicity or changing specifications for a return to the process, an internal recycling or even studying alternatives for recycling outside. In the case of solid waste, there are many papers on reuse. In general, the studies involve alternatives to reduce the possible toxicity and subsequent disposal. In some cases, the studies dealt with the residue already involve their use as material for construction (bricks). This work aims to evaluate two types of waste, namely, the drilling mud to clay-based generated by the activity of exploration and exploitation of oil and solid waste generated in the production process and catalyst for fluid catalytic cracking plant. In both cases, is currently the destination for industrial landfills, and the generating unit has to bear all expenses related to material handling. Our purpose in studying this waste, will initially study the temperature profiles. The dry material being ground and with a pre-determined size will be tested for physical-chemical, such as X-ray fluorescence (XRF) to see the composition and ASAP to analyze the surface area and pore volume. With this material treated in bench tests will be performed to assess the capability of removing nitrogen and sulfur contaminants in lighter fractions of petroleum. Preliminary tests with the industrial base of sorbent clay and zeolite showed a good result. These tests serve as a basis for comparison with material obtained in the laboratory.