Background and overview[1-2]
Trioctyl phosphate is a colorless, odorless, transparent, non-volatile oily liquid. It can be used as a cold-resistant plasticizer and as an additive for some synthetic fibers. Prepared from the action of octanol and phosphorus oxychloride.
Apply[3-4]
Trioctyl phosphate is a special plasticizer that has both flame retardancy and cold resistance. Its low temperature resistance is better than that of adipate esters. It has excellent water resistance and low volatility. It has excellent performance when combined with PVC resin. It has a gelling effect and can also give products excellent mechanical properties, UV stability, anti-aging, flame retardancy and antibacterial effects. It is mainly used in military PVC products, coatings, synthetic rubber and fibers. It can also be used as a working solvent for hydrogen peroxide (H2O2), lubricant additives, precious metal extractants, etc.
For example, to prepare hydrogen peroxide with a concentration of about 35%, its components and volume fractions in a unit volume where the volume fraction is set to 1000 parts are 100 to 120 parts of anthraquinone, and the rest are trioctyl phosphate and The volume ratio of heavy aromatic hydrocarbons, trioctyl phosphate and heavy aromatic hydrocarbons is 1:3. Put anthraquinone, trioctyl phosphate and heavy aromatic hydrocarbons into the reaction device, input hydrogen gas for hydrogenation reaction to obtain a hydrogenation liquid, put the hydrogenation liquid into In the reaction device, air is input for oxidation reaction to obtain the oxidation liquid, which is transported to the extraction tower and mixed with pure water. The volume fraction ratio of trioctyl phosphate to heavy aromatics is 1:3.6~4.4, and the volume fraction ratio of the oxidation liquid to pure water is 1:3.6~4.4. It is 1:1.6~2. The invention greatly optimizes the process flow, improves product quality and production speed, reduces energy loss and equipment occupation, reduces labor costs and production costs, and improves market competitiveness.
Another example is a papermaking wastewater treatment agent. The treatment agent consists of the following raw materials in parts by weight: 33-40 parts of bentonite, 10-18 parts of longan core, and 1-5 parts of sodium methyl silicate. parts, wollastonite 5-12 parts, trioctyl phosphate 8-16 parts. Longan core powder is obtained by pulverizing longan core, soaking in vinegar, and heat treatment; mixing and grinding bentonite and wollastonite, adding the prepared trioctyl phosphate solution, longan core powder, and sodium methyl silicate in sequence, heating and stirring, and then microwaves It can be obtained by processing, calcining at high temperature and lowering to room temperature.
The treatment agent of the present invention can greatly reduce various indicators such as COD, BOD, SS and metal ions in sewage. It is easy to use, improves water quality and protects the environment. All indicators of the treated sewage comply with GB18918-2002 standard. The invention is environmentally friendly, will not cause secondary pollution to water quality, is easy to recycle, has a simple production process and is easy to operate, has simple raw materials, a wide range of materials, low cost, and is suitable for large-scale production.
Preparation[5-6]
Method 1: A preparation method of trioctyl phosphate, the steps are as follows:
⑴ Synthesis process: Take isooctyl alcohol and raise the temperature to 47~53°C. Under stirring conditions, add phosphorus oxychloride dropwise to the isooctyl alcohol and control the temperature at 65±2°C within 4~6 hours. After the addition is completed, the reaction continues to equilibrate for 4 to 6 hours to remove the acid produced by the reaction and obtain crude ester;
⑵ Neutralization and equilibrium process: Add the crude ester to the alkali solution, stir and neutralize for 1 to 1.5 hours, the temperature is 70±3°C, and the neutralization control pH value is 8 to 9; after separation, the precipitate is obtained, and the precipitate is transferred to Wash 2-3 times in hot water at 80±2°C, control the pH value to 6.5~7.5, and separate and remove impurities, salt and water to obtain qualified wet crude ester;
Among them, the molar ratio of isooctyl alcohol:phosphorus oxychloride:lye is 2.5~3.2:1:1~1.6;
⑶ Negative pressure distillation and dehydration process: Separate the qualified wet crude ester through vacuum distillation, and take the 98~102°C fraction to obtain trioctyl phosphate.
Method 2: A production method of trioctyl phosphate, characterized in that the production steps are as follows:
1) Mixing process: First add a measured amount of octanol into the mixing kettle, cool it to below -15°C with frozen brine, then add a measured amount of phosphorus oxychloride in batches under vacuum conditions, when the temperature rises Stop adding when the temperature reaches 15-20°C, and add more when the reactants are cooled to below -15°C until the addition is complete. The molar ratio of phosphorus oxychloride to octanol is 1:3.10-3.15; then add measured Catalyst, the catalyst dosage is 0.5% of the mass of phosphorus oxychloride; the catalyst is titanium tetrachloride;
2) Esterification process: Under vacuum conditions of -0.097MPa, slowly heat up the above mixed materials, and control them in the early stage.The temperature rise speed is 15-20°C/h, so that the hydrogen chloride gas produced by the reaction can be discharged in time to reduce the occurrence of side reactions. The reaction lasts for 3 hours. When the material in the reaction kettle reaches 80-90°C, speed up the heating rate and control it at 30°C/h to speed up the reaction; when the reaction temperature reaches 110°C, add 10% of the above-mentioned octanol amount into the reaction system, continue to heat the reaction at a rate of 40°C/h to 150°C, and the reaction ends; After the mixing kettle, there is an air-exhausting hydrogen chloride absorption device connected through a conduit. The hydrogen chloride gas released by the reaction is absorbed by the absorption device connected to the mixing kettle, so that the generated hydrogen chloride gas can be discharged in time and prevent leakage into the air;
3) Neutralization and water washing: Pour the above reaction materials into the neutralization kettle, add 5-10wt% alkali solution, and neutralize. The neutralization temperature is 80-85°C, and the neutralization time is 0.5-1 hour. After reconciliation, remove the alkali solution; then wash it 2-3 times with 10wt% salt water, and then wash it 4-6 times with water until the washed water does not contain the sodium salt of the by-product dioctyl phosphate;
4) Dealcoholization: Pour the above materials into the dealcoholization kettle, and slowly raise the temperature to 120-130°C under the vacuum condition of -0.097MPa. When the amount of alcohol released is less, pass a certain amount of alcohol into the kettle. amount of steam, carry out stripping until the flash point of the product in the kettle is greater than 190°C, and stop dealcoholization; recover the removed alcohol, add it to the mixture of step 1) after rectification, and use it as a reaction raw material;
5) Refining: The above materials are neutralized with about 3wt% alkali solution at 80-90℃, neutralized for 0.5-1 hour, remove the alkali solution, and then washed with 5wt% brine for 2-3 times, and then wash with water 3-5 times until the acid value of the product is less than 0.1mgKOH/g;
6) Dehydration: Pour the above materials into the dehydration kettle, add activated carbon accounting for 0.1-0.2wt% of the materials to be dehydrated, and slowly rise to 130°C under vacuum conditions of -0.097MPa. When the moisture in the material is less than 0.1%, stop dehydration; filter the material to obtain the product.
Main reference materials
[1] Chemical Dictionary
[2] Production of trioctyl phosphate and its application in hydrogen peroxide production
[3] CN200710041693.9 A method for preparing hydrogen peroxide with a concentration of about 35%
[4] CN201611043147.4 A papermaking wastewater treatment agent and its preparation method and application
[5] CN201310120780.9 A synthesis method of trioctyl phosphate
[6] CN201310399695.0 A method for producing trioctyl phosphate BASF pigments
