SU963179A1 - Soluble glass binder - Google Patents

Abstract

Liquid glass binder for molding mixtures, including liquid glass and mineral supplement, characterized in that, in order to simplify the process of its preparation, to improve sanitary and hygienic working conditions and reduce the cost price of the binder, as a mineral additive, the binder contains used chromium-nickel catalyst in the production of synthetic rubber in the following ratio of ingredients, May.%: 75-99 Liquid glass Waste XP omni to an el e catalyst for the production of (/) synthetic 1-25 rubber. CO Y 00 4j with

Description

The proposed technical solution is designed to produce mold and core mixtures used to prepare casting molds and cores. A liquid glass binder, an aqueous alkaline solution of sodium silicate, is used to prepare molding and core mixtures flj. When using liquid glass mixtures have unsatisfactory knockability. A softening additive to liquid glass is known, including a basic sodium phosphorus salt and a 1-10% solution of hydrochloric acid 2j. This binder has a high cost and requires the use of special reagents. The closest to the invention in its technical essence and the effect achieved is a swelling link, including liquid glass and a mineral additive C. 3 C as a mineral additive in order to soften after heating to high temperatures. introduced based on calcium phosphorus in an amount of from 1 to 30%. . . The disadvantage of this binder is the difficulty of preparing the binder with the use of basic calcium phosphate salt as an additive, poor sanitary hygienic working conditions, as well as its high cost. To prepare the basic phosphoric calcium salt, it is necessary to prepare orthophosphoric acid, approximately 45% concentration, and dissolve calcium carbonate (chalk) in it in an amount that provides the pH of the product — the basic phosphoric calcium salt, not less than 7. This salt conglomerates and intergrowths, which makes it difficult to dose and introduce it into liquid glass. In the process of salt preparation, strict safety precautions are necessary, preventing the ingress of acid into open areas of the body, and an unpleasant odor that deteriorates working conditions. The aim of the invention is to simplify the preparation of a liquid binder and improve sanitary hygienic working conditions and cost reduction. The goal is achieved by the fact that the liquid glass binder of TS Forming mixtures, including liquid glass and mineral additives, contains a refined chromium-nickel catalyst as a mineral additive in the production of synthetic rubber in the following ratio of ingredients, wt.%: Liquid glass 75-99 synthetic rubber Liquid glass with a density of 1200–1500 kg / m3 is used to prepare the binder. The spent chromium nickel catalyst is obtained from the chromium nickel catalyst after it is used in the manufacture of synthetic rubber. The spent chromium-nickel catalyst of the IM-2-204 and IM-2206 grades consists of the following components: NU: STUO 4,5 H3R3-7-8 CaO 44-46 PjOg40-45 before the introduction. its in liquid glass. The presence of chromium nickel catalyst CaO and. determines the effectiveness of it as a softening agent in liquid glass mixtures. The binder is prepared as follows. A spent chromium-nickel catalyst is introduced into the water glass. The components are mixed until a homogeneous liquid product is cured, which is used as a binder. The spent chromium-nickel catalyst can also be introduced into the composition of liquid glass in the process of its preparation by the act-clave method. The invention is illustrated with binder compositions, physicomechanical and technological properties.

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sand mixture, which are listed respectively in Table. 1 and 2. Samples for dough testing are dried for 20 min. The work of knocking is determined by the method 5 of the CNIITMASH.

As follows from the table. 1 and 2, the spent chromium nickel catalyst does not reduce the initial strength of the liquid-glass mixture. At the same time, the operation of 10 knockout of mixtures with the addition of spent chromium-nickel catalyst and with a known binder is practically equal (mixtures 3, 4 and 8, -9, respectively) and in a number of cases when samples are heated to 15 ° C, it is zero ( mixtures 4-7) ..

Of. the table shows that the lower limit of the content of the spent chromium-nickel catalyst in the binder is 1%, since with its lower content the mixtures have unsatisfactory knockout performance, and the upper limit is 25%, since with a higher content of this material the properties of the mixtures are The basis 25 of the claimed binder does not change.

The spent chromium-nickel catalyst can be introduced directly into the composition of the molding mixture in the process of its preparation, however, JQ its consumption at the same time increases, and the efficiency decreases compared to its introduction into the composition of liquid glass.

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Using the invention, along with ensuring satisfactory properties of the mixtures, will significantly simplify the technology for preparing a binder based on liquid glass, sanitary and hygienic working conditions and reduce its cost. The simplification of the binder preparation technology is due to the lack of the need for special preparation of the spent chromium-nickel catalyst, as it is used in the delivery condition. In the process of preparing a sludge with a waste chrome-nickel catalysts, additional safety measures are not required, which improves the sanitary and hygienic labor conditions at the preparation site.

binder

Used chromium nickel catalyst,. introduced into the water glass according to the invention, is a waste product and is currently practically not disposed of. The estimated cost of 1 ton of spent chromium nickel catalyst, taking into account the loading and transportation, will be 5 rubles. Thus, the savings from the introduction of the claimed binder per 1 ton of binder will amount to 28 rubles.

Table t

95.2 95.2 0.8 0.8

four .

93.2 95.2 95.2 95.2 92.5 95.2 95.2 0.8 0.8 0.8 0.8 0.8 0.8 0.8

Ingredients

n: ei: i: i: ij: iziiiiii

10.0% 15.0% 25.0%. 25.5%

L (liquid glass with the addition of 5% basic salt. Calcium

10% - Continued table. one

The composition of the mixture, may.%

table 2

Claims (1)

LIQUID-GLASS BINDER for molding mixtures, including ingredients, liquid glass and a mineral additive, characterized in that, in order to simplify the process of its preparation, improve sanitary and hygienic working conditions and reduce the cost of the binder, the binder contains spent chromium-nickel catalyst as a mineral additive in the production of synthetic rubber in the following ratio in May,%: Liquid glass Spent chromium-nickel catalyst in the production of synthetic rubber.