SU1558871A1 - Method of photo catalyst production of ammonia - Google Patents

Abstract

The invention relates to the chemical industry and allows ammonia to be produced by reacting nitrogen and water in the presence of a photocatalyst under the action of UV irradiation. Moreover, nitrogen is bubbled at an optimal rate of 0.04 l / min through an aqueous suspension of a photocatalyst with a catalyst concentration of 0.017 wt.% :. The photocatalyst is unmodified titanium dioxide supported on silicon dioxide by co-flame hydrolysis of titanium tetrachloride and silicon. 2 tab.

Description

The invention relates to photocatalytic reduction of nitrogen to ammonia during the photolysis of water under the action of UV light and can be used in industrial technology for producing ammonia.

The purpose of the invention is to increase the yield of ammonia.

Example. 5 mg of unmodified titanium dioxide supported on silicon dioxide by co-flame hydrolysis of titanium tetrachloride and silicon was suspended in 30 ml of deionized water (which corresponds to the amount of photocatalyst — 0.017% by weight). The resulting suspension is poured into a pyrex reactor, which is a thin-walled pyrex tube with a length of 500 mm, an external diameter of 11 mm, an internal diameter of 10 mm, connected to a Schott filter. The reactor, filled with this suspension, is fixed vertically in a cylindrical chamber. A source of UV radiation is installed in the center of the chamber - a quartz quartz lamp DRT-1000. Eight holes are uniformly distributed around the lamp with a radius of 20 cm around the lamp to attach eight reactors. From the bottom, through the Shott filter, a stream of nitrogen, previously cleared of, is fed into the irradiated reactor. traces of oxygen and carbon dioxide at a rate of 0.04 l / min, which ensures an optimal mode of the photocatalytic process in this reactor and the photocatalyst in a suspended state. The outlet from the reactor is connected in series to an absorption column with a solution of hydrochloric acid (to trap partially carried ammonia) and a rotameter (to adjust the flow of nitrogen). The irradiation time is 60 s, after which the suspension is removed from the reactor and the aqueous solution forms (L

SP

GHS 00 00 4

The ammonia is separated from the photocatalyst, an aqueous solution is added to it from the absorption column, and the amount of ammonia formed is determined photocolorimetrically using the Neslér's method. The ammonia yield is 6.-10 g / min, g cat.

In order to select the optimal modes, the process of photocatalytic reduction of nitrogen to ammonia is carried out at room temperature, various values of nitrogen consumption and composition of the suspension. The results are shown in Table. one.

Table 1

As follows from Table 1e, the ammonia yield maximum is reached at nitrogen consumption and suspension concentrations, respectively, 0.04 L / min and 0.17 mg / ml, which are assumed to be optimal for the process.

Comparative studies on the proposed and known methods of photocatalytic ammonia production are given in Table 2,

Table 2

6.0-10

s

-3

As can be seen from the table.23 the proposed method of photocatalytic restorationN.Yatsola editor

Compiled by M Naumova Tehred M. Khodanych

Order 814

Circulation 404

VNIIL of the State Committee for Inventions and Discoveries at the State Committee for Science and Technology of the USSR 4/5, Moscow, Zh-35, Raushsk nab. 113035

Laziness of nitrogen to ammonia provides the yield of the final product, two orders of magnitude greater than the yield of ammonia obtained by a known method.

Claims (1)

Invention Formula A method of photocatalytic production of ammonia, including the interaction of nitrogen and water under the action of UV irradiation in the presence of a photocatalyst, characterized in that, in order to increase the yield of ammonia, nitrogen is bubbled through the aqueous suspension of the photocatalyst — non- modified titanium dioxide supported on silica by the joint plasma hydrolysis of titanium tetrachloride and silicon. Proofreader O. Tsiple Subscription