JPH01152190A - Manufacture of fuel oil having excellent hue stability - Google Patents

Abstract

PURPOSE:To manufacture a fuel oil having excellent hue stability during storage, by subjecting a light to heavy oil fraction produced through fluid catalytic cracking of heavy oil to adsorption treatment with a solid adsorbent so as to reduce the basic nitrogen content below a specified amount. CONSTITUTION:A light to heavy oil fraction produced through fluid catalytic cracking of heavy oil is subjected to adsorption treatment with a solid adsorbent (e.g., silica or zeolite) to reduce the basic nitrogen content to 20ppm or less, thus producing a fuel oil having excellent storage stability. The addition of a small amount of a lubricant to the oil before or after the above-mentioned adsorption treatment can further improve the hue stability.

Description

[Detailed description of the invention] Production of light! The present invention relates to a method for producing fuel oil with excellent hue stability from light oil to heavy oil fractions produced by fluid catalytic cracking of heavy oil.

In conventional fluid catalytic cracking of heavy oil, large amounts of light oil and heavy oil fractions called cycle oil are produced in addition to gasoline.
The fraction tends to turn yellow to brown during storage;
It is not preferable to use it as fuel oil. Conventionally, hydrogenation treatment has been carried out as a countermeasure against this discoloration, but there is a problem in that it is not economical because the amount of hydrogen consumed is large. Additionally, attempts have been made to add a hue stability improver as another method, but nothing has been found to be practically effective.

Solution 2 Problem to be Solved The present inventor investigated the hue stability of fuel oils made from the above-mentioned light oil to heavy oil fractions, and found that these fuel oils were adsorbed with a solid adsorbent to reduce the basic nitrogen content (201). l) II+
It has been found that the hue of the fuel oil can be stabilized by doing the following.

Therefore, an object of the present invention is to provide a method for producing fuel oil with excellent hue stability during storage from light oil to heavy oil fractions produced by fluid catalytic cracking of heavy oil.

The present invention will be explained in detail below.

The structural feature of the present invention is that the light oil to heavy oil fraction produced by fluid catalytic cracking of heavy oil is adsorbed with a solid adsorbent to reduce its basic nitrogen content to 20 ppm or less. The present invention is also characterized in that a small amount of lubricating oil is added before or after the adsorption treatment.

The fuel oil targeted by the present invention is light cycle oil (light cycle oil), which is produced by fluid catalytic cracking of heavy oil as a raw material using a powder catalyst such as zeolite or silica. The fraction constituting the above fuel oil is a light oil to heavy oil fraction rich in aromatic hydrocarbons with a boiling point range of about 150 to 400°C. It is abbreviated as LCO.

This FC-LCO is a cracked oil, and after being distilled from a fluid catalytic cracker, when it comes into contact with air, it begins to take on a yellow tinge within a short period of time, and then turns brown. Therefore, this discoloration phenomenon is not preferable when using FC-LCO as a fuel oil.

In the present invention, the FC-LCO is brought into contact with a solid adsorbent as soon as possible after distillation from the cracker, preferably before contacting with air.

Examples of the solid adsorbent used here include clay, silica, alumina, zeolite, etc., and are used in powder form or in the form of a molded body. To treat FC-LCO with this solid adsorbent, approximately 1 to 10% by weight of solid adsorbent, such as powdered clay, is added to the fuel oil, and the mixture is stirred at a temperature of 50 to 85°C for 5 to 20 minutes. Alternatively, it is preferable to fill a container with white clay molded into a spherical, cylindrical, etc. shape, and pour the fuel oil into the container and allow it to come in contact with the container for a sufficient period of time.

By bringing the oil into contact with the solid adsorbent as described above, contact conditions (temperature, time, etc.) are set such that the basic nitrogen content in the oil is 20 ppm or less, preferably 15 ppm or less, more preferably 10 ppm or less. Select.

The above treatment improves the hue stability of the oil by reducing the basic nitrogen content in the oil.

Further, in the present invention, hue stability can be further improved by adding a small amount of lubricating oil to the oil before or after the treatment of the solid adsorbent.

The lubricating oils used here include hydrorefining, solvent extraction refining,
It is purified by appropriately combining known methods such as dewaxing purification and adsorption purification, and has a viscosity of 5 to 30 cSt (at 40°C).
), containing a sulfide type sulfur content of 200 ppm or more, preferably 300 to 3000 ppm, and containing 5% by weight or more of tetralin and/or indane hydrocarbon, and a nitrogen content, particularly a basic nitrogen content, of 10 ppm or less is preferable. .

This lubricating oil is added in an amount of 0.5 to 5% by weight to the oil, and the selection of the amount added depends on the composition of the lubricating oil, but the sulfide sulfur content in the FC-LCO after addition is 10 ppm.
The above is preferably carried out so that the content of tetralin or indane hydrocarbon is 20 ppm or more, and the content of tetralin or indane hydrocarbon is about 0.05 to 3% by weight, preferably about 0.1 to 3% by weight. Incidentally, if the amount of sulfide sulfur content or tetralin in FC-LCO is insufficient, another source such as diphenyl sulfide, p-hydroxybenzyl sulfide, etc. may be added, or hydrogenation of FC-LCO You may also mix the tetralin-forming oil produced by.

The addition of the lubricating oil improves the hue stability of the fuel oil, improves the lubricity, and improves the wear prevention of the fuel injection nozzle of a diesel engine. Also,
If necessary, hydrogenation treatment may be performed, and an oxidation stability improver or the like may be added.

Incidentally, the heavy oil fluid catalytic cracking catalyst (FCC catalyst) itself can be used as the above-mentioned solid adsorbent, and furthermore, it can be reused as a catalyst in the above-mentioned fluid catalytic cracking reaction after adsorption treatment. It is economically advantageous for use as a solid adsorbent in

As shown in the examples below, the oil treated with a solid adsorbent in the form of soft soil according to the present invention has excellent hue stability, shows no discoloration during storage, and is suitable for lubricating oil. Since the oil to which is added has high lubricity, it is suitable as a fuel oil, and can also be used by mixing with other fuel oil base oils.

EXAMPLES The present invention and its effects will be specifically explained below with reference to Examples.

Example 1 Desulfurized heavy oil is subjected to fluid catalytic cracking using a zeolite catalyst to produce light cycle oil (FC-
LCO-A) was collected.

Next, 5% by weight of activated clay powder was added to the above-collected oil, and the mixture was stirred at a temperature of 60°C for 10 minutes to perform an adsorption treatment, and then filtered through a filter paper to obtain a purified oil (FC-LCO-B1). .

Table 1 shows the results of testing the properties and hue stability during storage of the oil before adsorption treatment (FC-LCO-A) and the oil after adsorption treatment (FC-LCO-Bl').

Table 1 (Note) Hue stability is based on 1) capacity of 200 tons of oil in a metal container.
a l and stored at room temperature under air contact for 30 days,
During that time, samples were taken into glass containers every 10 days and their appearance was evaluated.

As seen in Table 1, FC-LCO-Bl adsorbed with a solid adsorbent (shiratama powder) did not change color even when stored at room temperature for 30 days.

Example 2 Oil FC-LCO treated with solid adsorbent in Example 1
- A lubricating oil prepared as follows was added to Bl, and the hue stability during storage was tested. For reference, a similar test was also conducted on oil FC-LCO-A before solid adsorbent treatment. The results are shown in Table 2.

Preparation of lubricating oil: The fraction with a viscosity of 10.2 cSt separated from Middle Eastern crude oil was
Using i-Co-Mo hydrorefining catalyst, temperature 370
°C, hydrogen pressure 90 kg/cd, LHSV 1. The lubricating oil A was obtained by hydrorefining under Ohr conditions, followed by solvent film waxing and adsorption treatment with clay.

In addition, the above crude oil was mixed with furfural solvent at a ratio of 2.5 to the oil.
The raffinate was recovered by extraction using twice the volume, and then subjected to solvent film waxing and clay treatment to obtain lubricating oil B.

The properties of the obtained lubricating oil are as follows.

Properties: A1 viscosity cst
(40℃) 6.65 8.98 Sulfur content (wt%) 0.05 0.64 Sulfide sulfur content (ppm) 30 2600 Nitrogen content (p
pm) 20 15 basic nitrogen content (ppm) 1 or less 1 or less Total amount of tetralin and indane 15.4 10.6 (w
t%) As seen in Table 2, the oil treated with white clay (FC-LC
O-Bl) mixed with lubricating oil B containing a large amount of sulfide sulfur remained light yellow and did not change color even after being stored at a temperature of 60° C. for 30 days. On the other hand, the lubricating oil with a low sulfide sulfur content (Nct 9) and the lubricating oil with no sulfide content (Nct 12) turned brown. That is, it can be seen that the effect of greatly improving the hue stability of a specific lubricating oil FC-LCO is shown.

Claims (5)

[Claims] (1) The light oil or heavy oil fraction produced by fluid catalytic cracking of heavy oil is adsorbed with a solid adsorbent to reduce its basic nitrogen content to 2
A method for producing fuel oil with excellent hue stability characterized by reducing the content to 0 ppm or less. (2) The manufacturing method according to claim (1), in which the basic nitrogen content is 10 ppm or less. (3) The light oil or heavy oil fraction produced by fluid catalytic cracking of heavy oil is treated with a solid adsorbent, and at that time, before or after the treatment, a small amount of lubricating oil is added to the above fraction to remove its basic nitrogen content. A method for producing fuel oil with excellent hue stability, characterized in that the content of fuel oil is 20 ppm or less. (4) The lubricating oil has a sulfide sulfur content of 200 ppm or more and a tetralin and/or indane hydrocarbon compound of 5
Claim No. 3 (3) containing % by weight or more
) The manufacturing method described in section 2. (5) The manufacturing method according to claim (1) or (3), wherein the solid adsorbent is clay, silica, alumina, or zeolite.