ПЕРСУЛЬФАТ КАЛИЯ химические свойства, назначение, производство
Описание
Potassium persulfate, is composed of white crystals that are soluble in water, and it decomposes below 212°F (100°C). Potassium persulfate is a dangerous fire risk in contact with organic materials. It is a strong oxidizing agent and an irritant, with a four-digit UN identification number of 1492. The primary uses are in bleaching, as an oxidizing agent, as an antiseptic, as a polymerization promoter, and in the manufacture of pharmaceuticals.
Химические свойства
Potassium persulfate is a colorless or white,
odorless crystalline material.
Физические свойства
Colorless or white crystals; triclinic structure; density 2.477 g/cm3; stable in solid crystalline form; decomposes on heating, evolving oxygen; completely decomposes at about 100°C; sparingly soluble in cold water 1.75 g/100mL at 0°C; moderately soluble at ordinary temperature, 5.29 g/100 mL at 20°C;aqueous solution acidic and unstable, decomposing slowly at room temperature and more rapidly when the solution is warmed; insoluble in alcohol.
Использование
Potassium persulfate?is a powerful oxidant, commonly used to initiate polymerizations. Potassium Persulphate used for bleaching and textile desizing, as an oxidizing agent and antiseptic, in purification of ammonium sulfate, and in the manufacture of soap and pharmaceuticals. It is also used as al laboratory oxidant and photography chemical. It is a food additive.
Подготовка
Potassium persulfate can be prepared by electrolysis of a mixture of potassium sulfate and potassium hydrogen sulfate at a high current density:
2KHSO4→K2S2O8+ H2
Also, the compound can be prepared by adding potassium hydrogen sulfate,KHSOto an electrolyzed solution of ammonium hydrogen sulfate, NH4HSO4.
Общее описание
A white crystalline solid. Specific gravity 2.477. Decomposes below 100°C.
Реакции воздуха и воды
Water soluble. Slowly decomposed by water. The salt rapidly liberates oxygen when heated, and especially so when wet.
Профиль реактивности
Potassium persulfate is an oxidizing agent. Noncombustible but accelerates the burning of combustible material. Potassium persulfate plus a little potassium hydroxide and water released sufficient heat and oxygen to ignite a polythene (polyethylene) liner in a container. [MCA Case History 1155. 1955].
Опасность
Strong irritant and oxidizing agent. Fire risk
in contact with organic materials.
Угроза здоровью
Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or death. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause pollution.
Пожароопасность
These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard.
Сельскохозяйственное использование
Potassium sulphate, also called sulphate of potash, is a
white crystalline material, moderately hygroscopic,
available in fine, granular and semi-granular forms. It
contains 48 to 54% potassium (as K2O) and supplies 17 to
20 % of sulphate. Chloride-sensitive crops like tobacco,
grapes and potato require chloride-free potassium
fertilizers. Therefore, these crops are fertilized with
potassium sulphate, although this is more expensive than
potassium chloride. These three crops, being major
crops, account for about 7% of the total potash
consumption. For best results, potassium sulphate should
contain at least 50 % potash by weight.
Potassium sulphate occurs in nature as 'langbeinite' ,
a double sulphate of potassium and magnesium
(K2SO4?2MgSO4) and made from burkeite
(Na2CO3?2Na2SO4), kainite (KCl?MgS04?3H2O) or
potassium chloride (KCl) as follows:
When applied to soil, potassium ion from the watersoluble
potassium sulphate is retained in the soil colloids
and not easily leached out. This makes potassium
sulphate an excellent fertilizer, useful for all soils and
crops while sowing or before sowing. It is also a safe
ingredient of powdered, mixed fertilizers.
Профиль безопасности
Moderately toxic by
ingestion. An irritant and allergen. A
powerful oxidtzer. Flammable when
exposed to heat or by chemical reaction.
Can react with reducing materials. It
liberates oxygen above 100' when dry or @
about 50' when in solution. When heated to
decomposition it emits highly toxic fumes of
SOx,, S2O8, and K2O.
Возможный контакт
Potassium persulfate is used as a
bleaching and oxidizing agent; it is used in redox polymeri-
zation catalysts; in the defiberizing of wet strength paper
and in the desizing of textiles. Soluble in water.
Перевозки
UN1492 Potassium persulfate, Hazard Class:
5.1; Labels: 5.1-Oxidizer.
Методы очистки
Crystallise the persulfate twice from distilled water (10mL/g) and dry it at 50o in a vacuum desiccator. Its solubility in H2O is 1.6% at 0o, 4.5% at 20o, and 7.2% at 30o. An aqueous solution decomposes on long standing with evolution of O2 and formation of KHSO4. It is a powerful oxidising agent. Store it at ~10o. [Fehér in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 390 1963.]
Несовместимости
A strong oxidizer. Incompatible with
combustible, organic or other readily oxidizable materials;
sulfur, metallic dusts, such as aluminum dust; chlorates and
perchlorates. Attacks chemically active metals. Keep away
from moisture.
Утилизация отходов
Use large volumes of
reducing agents (bisulfites, e.g.). Neutralize with soda ash
and drain into sewer with abundant water.
ПЕРСУЛЬФАТ КАЛИЯ препаратная продукция и сырье
сырьё
препарат