The effect of chlorine and fluorine in platinum-zeolite catalysts on the isomerization of n-heptane
Тезисы доклада (Meeting Abstracts),
The 5th International Scientific School-Conference for Young Scientists “Catalysis: from science to industry”
25-29 сент. 2018
||Catalysis: from science to industry: proceedings of V International scientific school-conference for young scientists, September 25-29, 2018, Tomsk
"Ivan Fedorov" publishing. Tomsk.2018.
142 c. ISBN 9785917011325.
Institute of Hydrocarbons Processing SB RAS, Omsk, Russia
Omsk State Technical University, Omsk, Russia
Информация о финансировании (1)
Министерство науки и высшего образования Российской Федерации
By the beginning of 2018, the content of aromatic hydrocarbons in commercial motor gasoline is regulated in 123 countries. Thus, in Russia, according to the requirements of the Technical Regulations of the Customs Union, the content of aromatic hydrocarbons should not exceed 35 % vol., including benzene not more than 1 % vol. . In Russia, the key source of high-octane components of commercial gasoline is the reforming process, in which products the content of aromatic hydrocarbons can reach 80% wt., and the benzene content is 5% wt. As a result, modern enterprises for the production of gasoline that meet the requirements of technical regulations should have additional processes that allow obtaining non-aromatic high-octane components of gasoline.
One of such processes is the isomerization of paraffins of normal structure. In Russia over the past 10 years, the number of isomerization units in operation and under construction has doubled, and the content of branched paraffins in commercial gasoline has increased from 5-10 % to 12-15 % wt. [2, 3].
At present, the isomerization of pentane-hexane fractions is widely distributed at oil refineries. The catalysts of this process are sulfated zirconia, zeolite-containing and fluorinated alumoplatinum catalysts, chlorinated alumina. In the last two catalysts, fluorine and chlorine are the main sources of Lewis acid sites. The use of fluorine and chlorine as an acid component has also been widely used in the production of reforming catalysts.
A relatively new and promising process is the isomerization of n-heptane. The main feed for one is the straight-chain or recovered from the reformate heptane fraction 70-105 °C. As catalysts, systems based on molybdenum oxide, tungstate-containing or sulfated zirconia, borate-containing systems and systems based on zeolites are examined.
The aim of this work was to study the effect of fluorine and chlorine in platinum zeolite-containing catalysts on the isomerization reaction of n-heptane. For this purpose, halogens were introduced into the catalysts from hydrofluoric and hydrochloric acids, respectively, in various amounts and at different stages of synthesis. The carriers were a mixture of zeolite BEA and alumina in a ratio of 30 to 70 % wt. Platinum was deposited from hexachloroplatinic acid H2PtCl6 in an amount of 0.3 % wt. The main criteria for assessing the effectiveness of catalysts were the operating temperature, the yield of the target products and the selectivity for the target products.