49 results about "Tetrachlorophthalic anhydride" patented technology

The invention discloses a preparation method of pigment yellow 138, which comprises the following steps: synthesis: adding benzoic acid into a reactor, sequentially adding tetrachlorophthalic anhydride and 8-aminoquinaldine, heating to 140-160 DEG C, reacting for 1-3 hours, heating to 180-220 DEG C, reacting for 2-4 hours, cooling the reaction product to 130 DEG C, pouring into a previously prepared sodium hydroxide solution, reacting for 10-60 minutes, filtering, washing and drying to obtain a crude pigment yellow 138 product; and preparation of pigment: adding an organic solvent and the crude pigment yellow 138 product into a reactor, adding sodium methoxide or methanol solution thereof, heating to 40-80 DEG C, carrying out salification reaction for 1-3 hours, neutralizing by adding acid, precipitating the pigment in the form of molecules, distilling out low-boiling-point substances, heating to 80-150 DEG C, keeping the temperature for 1-6 hours to obtain slurry, filtering the slurry, washing, drying and pulverizing to obtain the pigment yellow 138. The invention has the advantages of high utilization ratio of raw materials, low environmental pollution, high product quality and favorable economic benefit.

The invention discloses an environmental-friendly long-lasting preservative packaging steel bucket and a preparation method thereof. The inner wall of the packaging steel bucket is coated by an anti-corrosion coating, and the anti-corrosion coating comprises the following components in parts by weight: a bisphenol A epoxy resin, an organic silicon modified epoxy resin, nano titanium dioxide, kieselguhr, tetrachloro phthalic anhydride, paraffin, propylene glycol, talcum powder, ethylene glycol, a thickening agent, a coupling agent, a surfactant, a defoaming agent and deionized water. As the inner wall and the surface of the packaging steel bucket are coated by the special anti-corrosion coating, the anti-corrosion property of the packaging steel bucket is effectively improved, the anti-corrosion coating is non-toxic and smellless, green and environmental-friendly, long-lasting in effect, low in production cost and good in economic benefit.

The invention discloses an industrial preparation method of 2,4,5-trifluoro-3-methoxybenzoyl chloride. The industrial preparation method comprises the following steps: 1) using methylamine to react with tetrachlorophthalic anhydride to get N-methyl tetrachlorophthalimide; 2) enabling the N-methyl tetrachlorophthalimide obtained in the step 1) to react with an alkali metal fluoride to get N-methyl tetrafluorophthalimide; 3) enabling the N-methyl tetrafluorophthalimide obtained in the step 2) to perform mixed reaction with sodium hydroxide to get 2,4,5-trifluoro-3-hydroxy sodium phthalate and then performing decarboxylation and acidification to get 2,4,5-trifluoro-3-hydroxybenzoic acid; 4) enabling the 2,4,5-trifluoro-3-hydroxybenzoic acid obtained in the step 3) to react with dimethyl sulfate to get 2,4,5-trifluoro-3-methoxybenzoic acid sodium and then acidifying to get 2,4,5-trifluoro-3-methoxybenzoic acid; 5) enabling the 2,4,5-trifluoro-3-methoxybenzoic acid obtained in the step 4) to react with thionyl chloride and N,N-dimethylformamide to get the 2,4,5-trifluoro-3-methoxybenzoyl chloride.