31 results about "P-acetaminophenol" patented technology

Disclosed is a process for preparing 5-aminosalicylic acid by gas phase catalytic carboxylation, characterized in that carbon dioxide is introduced into a system of p-acetaminophenol and a basic compound at a temperature of 150° C.˜220° C. and a pressure of 0.5˜5.0 MPa in the presence of a catalyst, so as to carry out a gas phase catalytic carboxylation reaction to form a 5-aminosalicylate, and the crude product 5-aminosalicylate is separated, and then acidified to prepare 5-aminosalicylic acid (5-ASA). Since the gas phase catalytic reaction replaces a solid phase thermo-chemical reaction, the reaction is significantly improved in terms of the process flow, reaction conditions, product quality and energy consumption. In addition, the reaction has a short reaction time, good selectivity, high yield and no formation of wastes during the reaction, and is suitable for industrial production.

The invention belongs to the field of fluorescent functional materials, in particular to a water-soluble silicon quantum dot and its preparation method, and its application in the high-sensitivity and high-selectivity detection of p-nitrophenol. The key points of the technical scheme of the present invention are: 3-aminopropyltriethoxysilane is added to ultrapure water at 85°C and vigorously stirred for 10 minutes, then added with acetaminophen solution, and continuously stirred for 5 hours. The silicon quantum dot synthesis method of the invention is simple and convenient, has mild reaction conditions, high quantum yield, good water solubility, long-term storage, and can maintain excellent fluorescence performance even under different pH and different ion strength conditions. The silicon quantum dot emits 495nm fluorescence under excitation of 398nm fluorescence, and p-nitrophenol can specifically quench the fluorescence of the silicon quantum dot. The silicon quantum dot of the present invention shows good application prospects in the aspects of fast, efficient, high selectivity and high sensitivity detection of p-nitrophenol.

The invention discloses paracetanol DC90 fine particles and a preparation method thereof. The paracetanol DC90 comprises following materials by weight ratio: 90 percent of paracetanol, 3.50 percent of cornstarch, 3.50 percent of pre gelatinized starch, 2.00 percent of povidone, 0.5 percent of crospovidone and 0.5 percent of stearic acid. Firstly, the paracetanol and the cornstarch are mixed evenly, then the pre gelatinized starch and the povidone are made into starch slurry to be used as bond which is evenly sprayed on the mixture of the fluidied paracetanol and cornstarch, fluidized bed granulation is carried out in the inlet air temperature, the wet particles are dried under the temperature of 80 DEG C and then are cooled at the temperature of 50 DEG C till water conforms to the requirement, the sizes of the particles are adjusted, the stearic acid and the crospovidone are added after the particle sizes are adjusted to be mixed evenly to obtain the paracetanol DC90 fine particles. The invention adopts the above technical proposal to inspect the product, and the particles are fine and uniform and have favorable fluidity, thereby being well and evenly mixed with other small quantities of active components powder.

The invention relates to a regeneration method of inactivated activated carbon in a refining stage of acetaminophen. The method comprises an alcohol-alkali desorption stage, a water scrubbing stage, an acid pickling stage and a drying and activating stage. The method has the characteristics of low regeneration cost, simple operation, high regeneration rate, and high economic benefits; almost no carbon is loss in the regeneration process and mechanical property of the activated carbon is not damaged in the regeneration process; the solvent can be recycled for many times and causes no secondarypollution; and the regenerated activated carbon can adsorb 250-285mg / g of methylene blue, and meets the process requirement of the refining and impurity removal stage of acetaminophen on the activatedcarbon.

The invention provides a preparation technique of p-acetaminophenoxide; the technique includes the following steps: adding phenol, oxammonium hydrochloride, acetic acid and polyphosphate with mass ratio of 1 : 0.85 : 3.0 : 8.5 to 1 : 0.96 : 4.1 : 9.6 into a reactor and sealing the reactor; carrying out reflux reaction for 3.0 to 5.2h under normal pressure and constant temperature in an oil bath of 75 to 85 DEG C; cooling to the temperature of 20 to 30 DEG C; adding ice water of 10 to 15 times of the volume of the mixed matters into the reactor and adjusting pH to 3.5 to 4.5 by using ammonia; adding nitrogen into the reactor to replace air; adding sodium bisulfite of 1 to 2 times of the weight of phenol and then sealing the reactor, continuously carrying out reaction for 5.0 to 7.2h under the normal pressure and constant temperature in the oil bath of 110 to 132 DEG C, cooling, decompressing and vaporizing the solvent water, then using acetone to wash so as to filter out ammonium phosphate salt, combing the filtrate, vaporizing and recycling the acetone to obtain the crude product, using water to re-crystallize to obtain the white crystal of the p-acetaminophenoxide. The preparation technique of the invention takes the phenol, glacial acetic acid and the oxammonium hydrochloride as the raw materials, takes the polyphosphate as a catalyst, adopts one pot method to prepare the p-acetaminophenoxide and has the advantages of simple technique, mild reaction conditions, low manufacture cost and being environment friendly.

A copper oxide / carbon nanotube / carbon nitride electrochemical sensor for detecting acetaminophen, a preparation method therefor and an application thereof. The method comprises: mixing carboxylated carbon nanotubes, carbon nitride, and water uniformly, and performing sonication; then adding copper acetate, mixing uniformly, and performing sonication; and drying after the sonication, and then calcining in an inert gas atmosphere to obtain a copper oxide / carbon nanotube / carbon nitride composite material. A CuO / CNT / g-C3N4 composite modified electrode is prepared and used as an electrochemical sensor for detecting acetaminophen. The electrochemical result shows that the composite material has a good detection effect on acetaminophen.

The invention provides a method for constructing a metal-organic framework-based specific modified electrode, which is to ultrasonically disperse an aminated metal-organic framework and reduced graphene oxide in N,N-dimethylformamide, and make the dispersion The modified electrode rGO‑NH was prepared by drop-coating on the surface of the polished glassy carbon electrode 2 -Cu 3 (btc) 2 / GCE; with rGO‑NH 2 -Cu 3 (btc) 2 / GCE modified electrode is the working electrode to form a three-electrode system; insert HAuCl 4 H 2 SO 4 In the solution, the gold nanoparticles were deposited on the electrode surface by the potentiostatic deposition method, and the specifically modified electrode Au / rGO‑NH 2 -Cu 3 (btc) 2 / GCE. The modified electrode can completely separate the oxidation peaks of acetaminophen and para-aminophenol, and realize the simultaneous detection of the two; moreover, the detection method is fast and simple, and has good anti-interference and stability.

The invention discloses a nanocomposite material, which comprises the following components in terms of mass parts: (2-3) parts of MWNTs, (1-1.5) parts of CeO 2 , (184‑188) parts of Nafion solution and 1000 parts of ultrapure water; compared with the prior art, the present invention provides a suitable modification material for the working electrode of the electrochemical sensor for simultaneously detecting acetaminophen and p-aminophenol, Utilizes CeO 2 The high catalytic activity of Nafion and Nafion, as well as the synergistic effect between the two and MWNTs, further enhanced the electron transfer ability, and improved the sensitivity and detection efficiency of acetaminophen and p-aminophenol detection.

The method of the present invention using acetaminophen to quickly calibrate the Raman spectrometer comprises: using a Raman spectrometer to collect the spectrum of the acetaminophen standard substance, collecting and obtaining n characteristic peak spectral peak positions; obtaining each characteristic peak spectral peak position difference ΔX n =X n -Y n , to calculate the average error ΔX 平均 =(ΔX 1 +ΔX 2 +ΔX 3 +...,ΔX n ) / n; Calculate the difference between each two consecutive measurement characteristic peak spectral peak positions L (n‑1)n =X n -X n‑1 , get the interval between two characteristic peak spectral peak positions; do difference calculation S for every two consecutive standard spectral peak positions (n‑1)n =Y n -Y n‑1 Get the interval between two standard spectral peaks; calculate the average shift coefficient A 平均 , when ΔX 平均 ≠0, modify the Raman spectrum measurement results, Z n修正后 =A 平均 *Z n +ΔX 平均 .