What are the necessary requirements for cosmetic surfactants?

2022-09-23 16:12:33

If the formulation design of cosmetics is flawed, it may cause abnormal skin reactions during use, which in turn may affect people's mood or health to some extent. Therefore, the raw materials for the production of cosmetics cannot have immune rejection reactions with the human body, that is, they must be non-irritating and non-toxic to the skin, hair, eye mask, etc., and have good appearance, skin feel, and good spreadability and stretchability.

In order to avoid potential safety hazards such as microbial contamination during use and storage, the relevant properties of surfactants should be fully considered in the formulation design of cosmetics. As a product that is in direct contact with the skin, cosmetics have much higher requirements on hygiene performance than other products. The health indicators of surfactants used in cosmetics mainly include heavy metal content, microbial content, substances prohibited by the state and other toxic substances. Amendment No. 26 of the European Council Directive 76/769/EEC on the restriction of the sale, use and preparation of certain toxic substances states that the limit of nonylphenol and nonylphenol polyoxyethylene ether used in various fields must be reduced from 1.0% To 0.1%, and it is required that cosmetic surfactants must have anti-microbial contamination properties.

Mechanism and application of surfactants in tertiary oil recovery.

1) Active water flooding. It is the only way to inject surfactant aqueous solution into the oil layer. The functions of the surfactant aqueous solution are: a reduce the dispersion of crude oil in water; b change the wettability of the formation surface; c increase the dispersion of crude oil in water; d Change the fluidity of crude oil, reduce crude oil maturity and ultimate shear stress.

2) Alkaline water flooding. Alkaline water flooding is a method in which naphthenic acid in crude oil reacts with alkali to form soap surfactants. This oil recovery method is low cost, but generally needs to add some co-surfactants to be more effective.

3) Thickening water flooding. Using thickeners to improve oil recovery, partially hydrolyzed polyacrylamide can be used as a thickener for injection water, and sometimes fatty alcohol polyoxyethylene ether sulfates or sulfonates and surfactants are mixed as thickeners.

Oil recovery from oil-bearing layers can be divided into three stages: primary oil recovery, which relies on the natural energy of the bottom layer to produce oil, and the recovery rate is less than 30%; secondary oil recovery, which uses water injection and gas injection technology to supplement the reservoir energy to produce oil, and The recovery rate can be increased to 40%-50%; tertiary oil recovery, using physical chemistry and biological technologies to strengthen the exploitation of remaining reserves, can increase the crude oil recovery rate to 80%-85%.

The tertiary oil recovery methods can be divided into four categories: first, thermal flooding, including steam flooding, combustion of oil layers, etc.; second, miscible flooding, including carbon dioxide miscible, hydrocarbon miscible and other inert gas miscible flooding; third, chemical flooding, including polymer flooding, Surface active area, alkaline water flooding and concentrated sulfuric acid flooding, etc.; Fourth, microbial oil recovery, including biopolymer and microbial surfactant flooding.