Catalytic reforming is a progressive technology with centuries of history

Useful properties of oil are known to mankind from time immemorial. It is used to produce fuel and raw materials for the production of synthetic fibers and plastics. At the same time, mankind has always sought to maximize the benefits of fossil fuel processing. One of these methods was catalytic reforming, the process that gave rise to high-quality gasolines and aromatic hydrocarbons. This method of oil refining was invented in the distant 1911, and since 1939 the technology has been applied on an industrial scale. Since then, the method of distillation of natural fuels has been constantly improved. To date, it represents one of the most complex and effective ways to produce gasoline with a high octane number.

Distillation of fuel

Catalytic reforming is the process of dehydrogenation (splitting of the hydrogen molecule from organic compounds) of six-membered naphthenes in the presence of nickel and some other metals of the platinum group at high temperature, which leads to the formation of aromatic compounds. In other words, this is a process that allows you to get a high-octane product - reformate - from low-quality raw materials - straight-run gasolines.

The main reason that reforming has become so widespread is the care of the environment. Prior to this, lead-based antidetonators were used to obtain gasoline with a high octane number . There are practically no emissions during reforming.

Products

Using this technology it is possible to extract the most valuable petrochemical raw materials - benzene, toluene, aromatic hydrocarbons. Today, catalytic reforming is the process by which up to 480 million tons of petrochemical products are produced per year around the world.

The main end product of the production cycle is reformate - gasoline with an octane number of 93-102. At the same time, by-products - paraffin hydrocarbons, as well as 90% hydrogen gas, which is the purest, than other methods, arise.

Another product that accompanies catalytic reforming is coke. It, depositing on the surface of catalysts, significantly reduces their activity. Its number is trying to reduce.

Catalytic reforming technology

As raw material for catalytic reforming, straight-run gasoline is a fuel with low octane number. The whole process is carried out in 3-4 reactors, which have a fixed catalyst bed. Reactors are connected with each other by pipes with a complex multi-chamber system and heating the transition product.

Catalytic reforming catalysts are a carrier-alumina (A1203) with impregnations of platinum crystals. In reactors at a temperature of 480-520 ° C and a pressure of 1.2-4 MPa, the feedstock is converted to high octane isoparaffinic and aromatic compounds. Very often, more expensive metals (rhenium, germanium, iridium), as well as halogens - chlorine and fluorine are introduced to increase the stability of the process in technology.

Types of catalytic reforming

To date, many methods have been invented to produce high octane gasoline and aromatic hydrocarbons through catalytic reforming reactions. Each foreign company keeps its own production method secret. However, they are all based on three main methods:

1. Reforming of oil, carried out simultaneously in three or four reactors continuously. Its essence is that the catalyst of the process first fully develops its potential, after which the reactors stop until the accelerator recovers its properties.
2. Continuous reaction in 2-3 units - the reagent is periodically restored in each system as it is developed. In this case, the process does not stop, and the regenerating reactor is replaced by a "floating", additional one.

The highest productivity can be achieved by continuous reaction with the use of regenerating plants and reactors. The catalyst, as its properties deteriorate, is placed in the regenerating chamber, and in its place comes the "recently restored reagent", the circulation of the aluminoplatin compounds occurs.

Main problem

The main problem that accompanies reforming is the formation of a large amount of coke, which reduces the catalytic properties of the aluminoplatin materials. The solution to this problem is to burn out coke deposits on the surface of the reacting elements with the aid of an oxygen-inert mixture at a temperature of 300-500 degrees Celsius. This process in a scientific environment is called regeneration. Completely restore the catalytic element is impossible. As it is used, it irrevocably ages, after which it goes to special factories, where platinum and other expensive metals are extracted from it.

Reactors for catalytic reforming

This method of processing natural fuels is carried out by various types of installations. Let's name a few of them:

• Selectoforming. Here, the reformer combines catalytic dehydrogenation with selective hydrocracking.
• Platforming. It has 3 reactors in its composition, and the operating time of the catalysts is from 6 to 12 months.
• Ultraforming. One of the first installations with a "floating" reactor, which carries out the process of recovery of the reagent.
• Isoplus. To obtain the product, the reforming and thermal cracking processes are combined.

The greatest distribution of oil reforming was in North America - it annually processes up to 180 million tons of natural fuel. On the second place are the countries of Europe - they account for 93 million tons. Russia closes the top three with an annual production of about 50 million tons of oil.