A kind of alkali-resistant gypsum retarder and preparation method thereof

Abstract

The invention provides an alkali-resistant gypsum retarder, which is prepared from the following components according to the mass percentage: 33% to 47% of amino acid, 25% to 35% of acid anhydride, 16% to 26% of activator, 6% of steel slag %~12%. The preparation method is as follows: uniformly stirring amino acid, acid anhydride and water, adding sodium hydroxide and steel slag, controlling the reaction temperature and time to obtain the alkali-resistant gypsum retarder. The obtained retarder can be used directly in a liquid form, or can be used in a powder form. The retarder can stably regulate the hydration rate of the building gypsum under alkaline conditions, and prolong the setting time of the building phosphogypsum and the building desulfurization gypsum. This method opens up a new way for the high-value utilization of steel slag, and plays an important role in promoting the high-quality utilization of industrial by-product gypsum.

Description

technical field

[0001] The invention relates to an alkali-resistant gypsum retarder and a preparation method thereof. In particular, the retarder has an excellent retarder effect on building gypsum under alkaline conditions. Background technique

[0002] Using industrial by-product gypsum to prepare building gypsum has low energy consumption and can be recycled. Its products have the advantages of light weight, fire prevention, heat preservation, and sound insulation. It has become a green building material recognized and widely used in the world. However, its fast setting and hardening and short operating time greatly limit the application of the product. In practical application, it is necessary to add retarder to control its hydration hardening speed and prolong its operable time.

[0003] Currently commonly used gypsum retarders mainly include organic acids and their soluble salts, alkaline phosphates, proteins, etc. Among them, the most researched and the most effecti...

Examples

Embodiment 1

[0018] By weight, mix 35% lysine hydrochloride, 30% maleic anhydride and 1.5 times water to make a mixed solution, then add 26% sodium hydroxide and 9% steel slag to adjust the pH of the system to 10 , reacted at 100°C for 2h, cooled to room temperature and dried to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

Embodiment 2

[0020] By weight, mix 47% lysine hydrochloride, 26% maleic anhydride and 1 times water to make a mixed solution, then add 20% sodium hydroxide and 7% steel slag to adjust the pH of the system To 7, react at 110°C for 0.5h, cool to room temperature and dry to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

Embodiment 3

[0022] By weight, mix 45% lysine hydrochloride, 29% maleic anhydride and 1.4 times water to make a mixed solution, then add 16% sodium hydroxide and 10% steel slag to adjust the pH of the system To 6, react at 90°C for 1 h, cool to room temperature and dry to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

technical field

[0001] The invention relates to an alkali-resistant gypsum retarder and a preparation method thereof. In particular, the retarder has an excellent retarder effect on building gypsum under alkaline conditions. Background technique

[0002] Using industrial by-product gypsum to prepare building gypsum has low energy consumption and can be recycled. Its products have the advantages of light weight, fire prevention, heat preservation, and sound insulation. It has become a green building material recognized and widely used in the world. However, its fast setting and hardening and short operating time greatly limit the application of the product. In practical application, it is necessary to add retarder to control its hydration hardening speed and prolong its operable time.

[0003] Currently commonly used gypsum retarders mainly include organic acids and their soluble salts, alkaline phosphates, proteins, etc. Among them, the most researched and the most effecti...

Examples

Embodiment 1

[0018] By weight, mix 35% lysine hydrochloride, 30% maleic anhydride and 1.5 times water to make a mixed solution, then add 26% sodium hydroxide and 9% steel slag to adjust the pH of the system to 10 , reacted at 100°C for 2h, cooled to room temperature and dried to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

Embodiment 2

[0020] By weight, mix 47% lysine hydrochloride, 26% maleic anhydride and 1 times water to make a mixed solution, then add 20% sodium hydroxide and 7% steel slag to adjust the pH of the system To 7, react at 110°C for 0.5h, cool to room temperature and dry to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

Embodiment 3

[0022] By weight, mix 45% lysine hydrochloride, 29% maleic anhydride and 1.4 times water to make a mixed solution, then add 16% sodium hydroxide and 10% steel slag to adjust the pH of the system To 6, react at 90°C for 1 h, cool to room temperature and dry to obtain a powder retarder. Wherein, the amount of water added is by weight of amino acid and maleic anhydride.

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