- Method for preparing dialkyl phosphinic acid or salt thereof
-
The invention discloses a method for preparing dialkyl phosphinic acid or salt thereof. The method is a method I or a method II. The method I comprises the following steps: in a solvent, in the presence of a free radical initiator and a catalyst, carrying out free radical addition reaction on phosphinic acid and olefin as shown in a formula (II) to prepare dialkyl phosphinic acid. The method II comprises the step: in a solvent, in the presence of a free radical initiator and a catalyst, carrying out free radical addition reaction on a compound shown in the formula (I) and olefin shown in the formula (II) to obtain dialkyl phosphinate. According to the method, high-purity and high-yield preparation of dialkyl phosphinic acid or salt thereof is achieved by adding the catalyst, subsequent complex purification work is avoided, the reaction time is remarkably shortened, and compared with the prior art, the method has the advantages of being simple, low in cost and high in purity.
- -
-
Paragraph 0117-0125
(2021/04/17)
-
- A extractant composition and its preparation method and application
-
The invention discloses extraction agent composition and a preparation method and the application thereof. The extraction agent composition comprises, by weight, a component A, specifically, 80wt%-99.99wt% of two-alkyl phosphonic acid which is of a structure shown as type I, a component B, specifically, 0wt%-5wt% of two-alkyl phosphine oxide which is of a structure shown as type II, a component C, specifically, 0wt%-10wt% of two-alkyl phosphonic acid alkyl ester which is of a structure shown as type III and a component D, specifically, 0wt%-5wt% of single alkyl phosphine oxide which is of a structure shown as type IV. The components B, C and D are not zero at the same time, and the total of the components A, B, C and D is always 100wt%. The prepared extraction agent composition containing a synergistic extractant component serves as an extraction agent and can be applied to rare earth metal, in particular to separation and purification of cobalt nickel metal. Compared with a single component extraction agent, the extraction property of the extraction agent composition is more excellent; and compared with bi-(2, 4, 4'-trimethylpentyl) phosphinic acid, other synergistic extractant components are all easy to be compounded, and thus producing cost of products is lowered.
- -
-
Paragraph 0079; 0080
(2018/11/22)
-
- Microwave-assisted synthesis of dialkylphosphinic acids and a structure-reactivity study in rare earth metal extraction
-
Dialkylphosphinic acids were synthesised by a microwave-assisted method with high yields and wide substrate applicability. A structure-reactivity study indicates that an increase in steric hindrance in the β position led to a decrease of extraction ratio and heavy rare earth element separation activity. A computational study was also conducted to understand the steric effect.
- Du, Ruo-Bing,An, Huaying,Zhang, Suhui,Yu, Donghai,Xiao, Ji-Chang
-
p. 104258 - 104262
(2015/12/24)
-
- Process for the preparation of highly purified, dialkydithiophosphinic compounds
-
An improved process for production of dialkyldithiophosphinic acid including sulfurizing a purified dialkylphosphinic acid by: reacting a hypophosphorous acid or salt with a stoichiometric excess of an alpha olefin in the presence of a free radical initiator to form a reaction product comprising monoalkylphosphinic acid and dialkylphosphinic acid; adding sufficient aqueous base to the reaction product to i) form the salts of the phosphinic acids, and ii) establish an aqueous phase and an organic phase, wherein a monoalkylphosphinic acid solubilizes into an aqueous phase; separating the organic phase from the aqueous phase; acidifying the organic phase and removing the olefin from the organic phase; isolating the purified dialkylphosphinic acid product; and sulfurizing the purified dialkylphosphinic acid product to form a dialkydithiophosphinic acid. The present invention also provides a process for preparing purified dialkylthiophosphinic chloride, and a process for preparing purified dialkylmonothiophosphinic acids.
- -
-
Page/Page column 6
(2008/06/13)
-
- NOVEL PHOSPHINIC ACIDS AND THEIR SULFUR DERIVATIVES AND METHODS FOR THEIR PREPARATION
-
The present invention provides phosphinic acids and their sulfur derivatives, in accordance with the following formula (I): wherein R1 and R2 are different and each of R1 and R2 is independently selected from an organic radical that branches at the alpha carbon and an organic radical that branches at the beta carbon, and each of X and Y is independently O or S, and wherein said compound is a liquid at room temperature. Compounds of formula (I) find utility for example as metal extractants. Also provided are methods for making compounds of formula (I) and their corresponding phosphine intermediates.
- -
-
Page/Page column 25-28
(2008/06/13)
-
- PROCESS FOR THE PREPARATION OF HIGHLY PURIFIED, DIALKYL PHOSPHINIC ACIDS
-
In a process for the production of dialkylphosphinic acids, especially branched, dialkylphosphinic acids in high purity via the reaction of an alpha olefin with a hypophosphorous acid or a salt thereof, the improvement comprising conducting the reaction in the presence of a stoichiometric excess of the olefin and isolating and purifying the desired dialkylphosphinic acid product by neutralizing the monoalkylphosphinic acid by-product with an aqueous base; removing the aqueous phase in which the neutralized monoalkylphosphinic acid is preferentially solubilized; acidifying the dialkyl product in the organic phase; and isolating the purified product.
- -
-
Page/Page column 4
(2008/06/13)
-