SU1084243A1 - Reagent for decomposing calcium hypochloride in calcium chloride solutions and method for preparing same - Google Patents

Abstract

1. A reagent for the decomposition of calcium hypochlorite in solutions of calcium chloride containing ferric chloride (III, characterized by I. 1 J | 3 ... v; l (since, in order to increase the stability of the reagent, it additionally contains chloride (S) and potassium chloride in the following ratios of ingredients, mol.%: Ferric chloride (llJ Potassium chloride 4-9 Ferric chloride (P) Remaining 2. A method for preparing a reagent for the decomposition of calcium hypochlorite in chloride solutions by chlorination of iron with condensation of vapors on potassium chloride, characterized in that, in order to increase st decomposition of the calcium chlorite hypoe, chlorination is carried out at 650i5 ° C and supplied (L of chlorine at a rate of 0.20-0.25, l / h cm, and vapor condensation is carried out on a potassium chloride of 1.6-2, 8 mm at 600-650 C.

Description

The invention relates to the metallurgy of non-ferrous and rare metals, in particular, to the widely used method of producing calcium chloride free from calcium hypochloride, in the processes of utilization and neutralization of chlorine-containing gases, discharges of various productions by the known milk Ca (OH). A known reagent for the decomposition of calcium hypochlorite is Ca (CU), which is an aqueous or hydrochloric solution of nickel chloride, copper (I) chloride and ferric chloride (1 CONTAINED in a ratio of 1: 1: 3 (calculated as HYDROXIDE. SI) l The lack of reagent is its instability over time, a decrease in storage efficiency, therefore it is used only freshly prepared to avoid the formation of hydroxides before calcium chloride is added to the solution. In addition, the reagent contains expensive nickel and copper chlorides. standing In this process, the components of the hydroxide reagent are filtered out along with the sands from the calcium chloride solution and dumped into waste dump, i.e. valuable components are irretrievably lost. A significant drawback is the toxicity of copper and nickel compounds, which are extremely dangerous. and hazardous substances their use leads to environmental pollution.The aim of the invention is to increase the stability of the reagent. This goal is achieved by the fact that the reagent for the decomposition of calcium hypochlorite in solutions of calcium chloride containing ferric chloride (l additionally contains ferric chloride (U) and potassium chloride in the following ratios of ingredients, mol. Ferric chloride (III) 9-31 Potassium chloride 4-9 Ferric Chloride (it) Else With this, nickel and copper chlorides are completely eliminated. Reagent is obtained in a compact form (alloy of salts) and it can be stored (in sealed packaging) for a long time. Also, in the method of producing reagent for the decomposition of calcium hypochloriteCalcium chloride solutions. The process is carried out by chlorinating 432 iron at 650–5 ° C and feeding chlorine at a rate of 0.20–0.25 l / h cm, vapor condensation is carried out on potassium chloride with a particle size of 1.6–2.8 mm at 600–650 ° C. Example 1. Experiments to determine the stability of calcium hypochlorite are carried out in a solution of milk of lime after chlorination, the concentration of calcium hypochlorite in which is determined by the content of active chlorine and is 3.7 g / l. In the course of the experiments, two parallel samples of the test solution of 15 ml each were taken. A reagent for decomposition of calcium hypochlorite is added to one of them, allowed to stand for 1 min and analyzed for Ca content (ClOj. The results of the experiments are given in Table 1. It can be seen from the table that almost complete decomposition of calcium hypochlorite can be carried out with reagent 2 and 3. The degree of decomposition of Ca (C10) 2 with pure ferric chloride is low — 16.5% even at a Fe CBj concentration of 7.55 g / l. Excess potassium chloride (above 10%) is undesirable, since this will lead to a change in the electrolyte composition and its additional adjustment when electrolytic p Calcium extraction. Thus, the most optimal for the decomposition of calcium hypochlorite is a reagent of the following composition, mol.%: Fe, 31, Fe C 60-87; KC1 4-9. The effectiveness of a known reagent drops sharply with its restraint. Thus, the degree of decomposition Calcium hypochlorite with a reagent prepared 24 hours before the experiment is reduced from 99.2% to 43% (experiment 7, table 1). However, there was no change in the stability of this reagent for a year. The reagent obtained by the prototype method does not provide a sufficient degree of decomposition of calcium hypochlorite (test 8, Table 1). Example 2. Iron scrap is chlorinated at 650 ° C in a quartz cell of 30 mm connected to a 45 mm quartz glass. The lower part of the glass is a collection of the flowing salt mixture, and the upper part separated from it by a false bottom is filled with potassium chloride. The height of the salt column is 100-120 mm. The temperature of the collector and the lower part is maintained at a predetermined value constant within 12 ° C. The resulting salts are analyzed for iron (11) and (110) chlorides. The results of experiments, depending on the size of KC1 and temperatures (at a chlorine feed rate of 0.2 l / h cm) to chlorinator, are given in Table 2. From Table. 2, it can be seen that a mixture of the required composition can be obtained on a salt nozzle with a particle size of 2.81.6 mm at a temperature of 600-650 0. A decrease in temperature and an increase in particle size of KC1 lead to a drastic decrease in the content of ferric chloride (C) in the mixture. reducing the size of the salt nozzle reduces the content of chloride glands (110 in the resulting mixture. This can be explained by the fact that with an increase in condensation surface and temperature, the probability of thermal decomposition of ferric chloride (110 increases. Thus, a change in the set values — temperature and particle size KC1) will result in a deviation from the boundary values of the ingredients of the object. The results of experiments to determine the effect of the rate of chlorine supply to the chlorine on the composition of the resulting salt mixture with a KS1 particle size of 2.8 mm are given in Table. 3. From table. 3, it can be seen that the optimal feed rate of chlorine to the chlorinator is 0.20-0.25 l / h. The chlorination temperature of scrap iron is 650i5 C. A change in temperature (decrease or increase) leads to a change in the ratio of ferric chloride (II and Sh) to steam phase. For example, an increase to 700–750s leads to a 1.5 times decrease in the content of ferric chloride (III) due to dissociation into ferric chloride and chlorine. A decrease in the chlorination temperature leads to the predominant formation of ferric chloride (llfi. Thus, in the chlorination of scrap iron with a chlorine feed rate to a chlorinator of 0.20-0.25 l / h with the condensation of the ferric chloride formed on the salt nozzle of potassium chloride of particle size 2, 8-1.6 mm, heated to 600-650 C, can be obtained reagent for the decomposition of calcium hypochlorite. The proposed method will provide the most simple in composition of the reagent, the preparation of which can be organized directly at the enterprise to consume le waste from production. The loss of valuable components such as nickel and copper are excluded, the wastewater is neutralized, and the reagent obtained is much more stable and easy to handle.

1084243

8 Continued table. one

7. Fe C1 "- Ni Cu Ql

Freshly prepared 99.2 After 24 hours aging 43.0

B. By method-type

KC1-25 (Fe Clfl.uD21.0 Characteristics Temperature of the composition 550 600 I 600 7.0, 7.06.35.0 Fineness 6.36.35.02.2 KC1, mm Content in a mixture of Fe Cl-, mol.% 52 , 8 52,041,221,1 Content in the mixture of Fe Sdl 2.410,17,469,7 mol.% Content in the mixture KC1, 44,7 38,041,423,3 mol.%

Table 2 salt nozzle ,, With T 600 TbOO I 650 | 650 tb50 | 650 gb50 2.87,06,35,02,81,6 1,66,35,02,81,6 1,244,336,19,91,12,1 4,510,812,962,087,789,1 9,044,9, 50,928,111,28,1

Claims (1)

1. The reagent for the decomposition of calcium hypochlorite in solutions of calcium chloride containing chloride (iron (BUT, characterized in that, in order to increase the stability of the reagent, it additionally contains iron chloride (P) and potassium chloride in the following ratios of ingredients, mol.% : Ferric Chloride (Πί Potassium Chloride Ferric Chloride (11) 2. Production Method 9th 4-9 The rest of the reagent for the decomposition of calcium hypochlorite in calcium chloride solutions by iron chlorination with vapor condensation on potassium chloride, characterized in that, in order to increase the degree of decomposition of calcium hypochlorite, chlorination is carried out at 65O + 5 ° C and the flow of chlorine at a rate of 0.20-0 , 25 l / h.cm ² , and vapor condensation is carried out on potassium chloride with a particle size of 1.6-2.8 mm at 600-650 “s.