146results about How to "Weak acid" patented technology

The present invention discloses an aluminium oxide carrier which contains magnesium and phosphorus, also can contain potassium and its preparation method. The magnesium, phosphorus and potassium can be added in the process of preparation. Said carrier is low in acidity and has large pore volume and large specific surface area. The catalyst prepared by using said carrier has the features of strong anti-coking property and good stability.

A pharmaceutical composition useful for sustained/extended release of a therapeutically active ingredient to an environment of use, said composition comprises a tablet core composition consists of a therapeutically active ingredient that is weakly acidic in nature and has a limited solubility in the aqueous environment, said the therapeutically active ingredient is in immediate contact with the agents that are capable of improving the solubility of the agent within the core, for e.g., by changing the micro environmental pH of the core and the tablet core is surrounded by a release rate controlling membrane consisting of a semi-permeable membrane forming polymer, permeable membrane forming polymer, and at least one plasticizer capable of modulating the film formation properties of the polymers.

The invention relates to a method for producing chitin, calcium citrate and albumen powder by using the shells of crustaceans like shrimps and crabs as the materials; the shells of shrimps and crabs are selected and arranged into an oven, and dried and then water with weight of 6 times of the shells are added; then the mixture is heated to be between 50 and 55 DEG C; then a neutral papain with a mass ratio of 1: 0.001 to 0.003 with the shells of shrimps and crabs, is added for carrying out zymohydrolysis and obtaining zymohydrolysis liquid; the zymohydrolysis liquid is filtered for obtaining the shells of shrimps and crabs; 15% to 20% citric acid solution is added for dipping for 24 to 36 hours; then the chitin is obtained through filtering, acid rinsing and drying; cold separation is carried out on the filtered liquid and a cold separation matter which can be named the calcium citrate is obtained through centrifugalizing; vacuum condensing and drying are carried out on the rest liquid obtained through centrifugalizing, thus obtaining the albumen powder. In the invention, the technical method adopts enzymes for removing proteins and citric acid decalcification for leading the separation of the protein and the calcium with the chitin to be more complete; the yield rate of the chitin is high; and the prepared chitin product has the advantages of white color, high purity and good quality.

The invention discloses a dimethyl benzyl alcohol hydrogenolysis catalyst and a preparation method thereof. The catalyst comprises 35-70wt% of copper oxide, 5-25wt% of zinc oxide, 15-40wt% of silicondioxide, 0.5-15wt% of alkaline earth metal oxide and 0.1-5wt% of bismuth oxide and lead oxide. The preparation method comprises the following steps: (a) adding a mixed solution containing a Cu compound, a Zn compound, an alkaline earth metal compound, a Bi compound and a Pb compound and an alkaline precipitant solution into a silica sol aqueous solution for precipitation reaction and heating aging; (b) filtering, washing, drying and roasting the aged slurry to obtain complex compound powder; and (c) adding a binder, a forming assistant and the like into the complex compound powder, fully mixing, extruding and forming, drying and roasting to obtain the catalyst. When used for preparing cumene by hydrogenolysis of dimethylbenzyl alcohol, the method not only has good activity and selectivity,but also has good liquid resistance and high mechanical stability.

The invention is a process method for unblocking water and oil wells in an oil field by biological acid, characterized by mixing biological acid and water as well as assistant into unblocking agent, squeezing the unblocking agent into oil or water well at normal temperature, so that the unblocking agent gradually seeps into strata, the biological acid seeps into throats to enter in micro-scopical holes and are absorbed on the surface layers of cores, where the squeezing radius is 1-15 m, pressure is stabilized for 0-1.5 h, and 4-18 h later, opening the well,and not discharging fluid, thus improving core property, recovering stratum permeability, stopping stains redeposition, reducing oil and water interface tension and raising crude oil recovery.

The invention discloses a hydrocracking catalyst and a preparation method thereof. In the catalyst, the acidic component is a silicotungstate, the hydrogenation metal component is nickel, and the carrier is silicon oxide. The catalyst is prepared by: adding a nickel salt and an alkali metal salt respectively into an aqueous solution containing organic acid I to obtain a solution A, adding a silicon source into a solution containing organic acid II to obtain a solution B, then mixing the solution A with the solution B, adding a silicotungstic acid aqueous solution, conducting stirring to evaporate the solution, and carrying out drying and roasting, thus obtaining the catalyst. The heteropolyacid used by the method is silicotungstic acid, and two organic acids are used cooperatively to reach a mutual promotion effect, so that the metal components and the acidic component are dispersed more evenly, the hydrogenation activity and the acid function are matched better, and also the catalyst can have larger specific surface area, pore size and pore volume. Thus, the catalyst has better catalytic performance. The catalyst prepared by the invention is especially suitable for a hydrocracking reaction of long chain alkane.

The invention relates to a method for preparing an alpha-phenylethanol catalyst through hydrogenation of acetophenone and application. The catalyst contains copper oxide, zinc oxide, silicon dioxide and bismuth oxide. The method of the catalyst is realized by virtue of a sub-step precipitation method and comprises the following steps: precipitating zinc salt and a precipitator at a certain temperature, and aging, so as to obtain slurry (1); adding a mixed solution of copper salt and bismuth salt as well as the precipitator into the slurry (1), carrying out coprecipitation, and aging, so as toobtain slurry (2); adding carrier silicon into the slurry (2), and uniformly stirring and mixing, so as to obtain slurry (3); filtering, washing, drying and roasting the slurry (3), so as to obtain catalyst powder; adding a certain amount of pore forming agents into the catalyst powder, and carrying out piece formation; and carrying out secondary roasting on the formed catalyst, so as to obtain the final catalyst. The catalyst prepared by virtue of the method is large in pore volume and aperture, good in mass transfer property and heat transfer property and high in activity and selectivity.

The invention discloses a preparation method of bamboo dissolving pulp. The preparation method disclosed by the invention comprises bamboos as the raw material and comprises the following steps: pre-hydrolyzing bamboo chips through diluted acetic acid, stewing the pre-hydrolyzed raw material with sulphate, processing pulp through oxygen delignification, extracting the pulp with cold caustic, bleaching with D0-(EP)-D1, and thus obtaining the bamboo dissolving pulp. The prepared bamboo dissolving pulp is more than 90% of ISO (International Standardization Organization) in whiteness, more than 92% in content of alpha-cellulose, 959 ml/g in intrinsic viscosity, 3.23% in content of pentosan, 0.11% in content of ash, and 38% in yield; compared with the yield of 30-35% in the common process currently, the yield of the bamboo dissolving pulp disclosed by the invention is at least increased by 3-8%, and therefore, the preparation method of the bamboo dissolving pulp disclosed by the invention has great economic benefit.

The invention relates to an acetophenone hydrogenation catalyst and a preparation method thereof, which comprises the following steps: (1) hydrochloric acid, F127, KCl, 1,3,5-trimethylbenzene and polymethyl methacrylate microspheres are mixed evenly, then tetraethylorthosilicate is added to the mixture, and 4-12 hour later, a sol is obtained; (2) a mixed metal salt solution containing Cu, Mn, Bi and Pb is prepared, a solution of an alkaline precipitant is prepared, the two kinds of solutions are allowed to contact with the obtained sol for precipitation reaction, heating and aging to obtain aslurry; (3) the slurry is subjected to filtering, washing, drying and roasting to obtain composite compound powder; (4) the composite compound powder is mixed with a binder, an alkaline auxiliary agent and a forming auxiliary agent and extruded to obtain the catalyst. The catalyst active component copper prepared by the method has high dispersion, the acidity is weak and mass transfer performanceis good, side reactions such as hydrogenolysis and the like are effectively inhibited, and good activity and selectivity are obtained.

The invention discloses a halogen-free water-soluble flux with weak acidity and low corrosion, which comprises the following components in percentage by weight: 3 to 8 percent of organic acid and organic amine active agent, 0.5 to 2 percent of halogen-free surfactant, 1 to 15 percent of cosolvent, and the balance of deionized water. A preparation method comprises the following steps of: weighing the organic acid and organic amine active agent, the halogen-free surfactant and the cosolvent, putting the deionized water and the organic acid active agent into a stirring kettle, uniformly stirring, sequentially adding the cosolvent and the halogen-free surfactant in the stirring process, and uniformly stirring to obtain a finished product. Compared with the conventional water-soluble flux, the halogen-free water-soluble flux has the advantages that: 1, the flux has weak acidity and low corrosion, and small damage to welding equipment and appliances, improves production efficiency and reduces production cost; and 2, the flux does not contain halogens at all, so that a printed circuit board has high electric property, high reliability and long service life and meets the halogen-free requirement after being welded, and the application field and application range of the water-soluble flux are greatly expanded.

This invention relates to a method for preparing an acid addition salt of a polyacidic basic compound, or a water adduct having basic site(s) stronger than pyridine. The method comprises reacting the polyacidic basic compound with an acid salt of pyridine. By the present invention, the number of moles of an added acid in the acid addition salt of the polyacidic basic compound can be readily changed to a number suited for the polyacidic basic compound as needed.

The invention discloses a rust remover and a preparation method thereof. The rust remover is prepared from the following components in percentage by mass: 60 to 80 percent of organic acid, 19 to 39 percent of inorganic acid and 0.8 to 3 percent of corrosion inhibitor, wherein the organic acid is one or more than two kinds of tartaric acid, citric acid, oxalic acid and trichloroacetic acid; the inorganic acid is one or more than two kinds of sulfamic acid, phosphorous acid and ammonium acid fluoride; and the corrosion inhibitor is benzotrizaole or/and sodium dihydrogen phosphate. According to the rust remover disclosed by the invention, the use of hydrochloric acid or sulfuric acid is completely avoided; no acid mist during rust removal is generated, the corrosion to equipment in a workshop is avoided and the labor environment is improved; meanwhile, the corrosion inhibitor is weaker in acidity, the over corrosion to workpieces is avoided and the condition that the skin of an operator is severely corroded is prevented; in addition, after a certain amount of workpieces are treated, the rust removing efficiency is reduced; and by continuously adding the rust remover disclosed by the invention, the rust removing efficiency can be restored, i.e., a rust removing bath solution disclosed by the invention can be conveniently and repeatedly used.

Provided are halogen-free flame-retardant high-temperature-resistant polyester elastomers and a preparation method therefor. The provided polyester elastomers comprise the following raw materials, by weight, 20-50 parts of polyester elastomers, 10-30 parts of polybutylene terephthalate, 2-10 parts of compatilizer, 10-30 parts of phosphor-nitrogen flame retardant, 5-20 parts of phosphonate flame retardant, 2-5 parts of acid absorbing agent, 3-8 parts of flame retardation synergistic agent, 0.3-0.8 part of anti-oxidant and 0.5-2 parts of anti-hydrolysis agent. The preparation method is as follows: polyester elastomers and polybutylene terephthalate are subjected to drying processing, and are mixed with other ingredients uniformly in a high-speed mixing machine; discharging is carried out, the mixture is subjected to bar drawing and granulation by a double screw extruder, and halogen-free flame-retardant high-temperature-resistant polyester elastomers are prepared. The defects of the prior art are overcome, on the premise that present device configuration and technological parameter setting are not changed, an optimal solution is provided that halogen-free flame-retardant high-temperature-resistant polyester elastomers can be produced stably, the high temperature resistance of the material is improved obviously, the flame resistance is raised greatly, and other performances are optimized.

The invention belongs to the field of Fischer-Tropsch synthesis catalytic hydrocracking, and discloses a Fischer-Tropsch synthesis wax hydrocracking catalyst, a preparation method thereof, and a Fischer-Tropsch synthesis wax hydrocracking method. The preparation method of the Fischer-Tropsch synthesis wax hydrocracking catalyst comprises following steps: 1, amorphous silicon aluminium and a binderare subjected to mixing kneading, strip extrusion moulding, primary drying, and primary roasting to obtain a catalyst carrier; and 2, the catalyst carrier is immersed in a dipping solution containinghydrogenation active metal elements and a competitive adsorbent, and secondary drying and secondary roasting are carried out to obtain the Fischer-Tropsch synthesis wax hydrocracking catalyst, wherein the hydrogenation active metal elements contain at least one metal element selected from VIII family in the periodic table of elements, and at least one metal element selected from VIB family in theperiodic table of elements at the same time, and the volume amount of the dipping solution containing hydrogenation active metal elements accounts for 65 to 85% of the pile volume of the catalyst carrier. The hydrogenation active metal components of the catalyst are excellent in dispersibility, and intermediate fraction oil selectivity is high.

The invention discloses a preparation method for a supported solid-acid catalyst for synthesising 2-isonaphthol via the one-step hydroxylation of naphthalene, belonging to the technical field of supported solid-acid catalysts, wherein via the technical scheme of soaking a supporter in a solution containing an auxiliary constituent precursor in a vacuum condition, vibrating and drying in a low-temperature water bath, and calcining for 1-3 hours at 400-600 DEG C at first, and then soaking the calcined powder in the solution containing an auxiliary constituent precursor in a vacuum condition, vibrating and drying in the low-temperature water bath, and baking in an airflow at 110-300 DEG C, a solid-acid catalyst which is adjustable in surface acidity and high in the dispersibility of active constituents is prepared. With the adoption of the method, the various problems existing in the prior art are effectively solved, the conversion rate of naphthalene and the selectivity of 2-isonaphthol are greatly increased, and good effects are obtained.

The invention relates to a method for extracting persimmon leaf tartaric acid which is an active ingredient in a persimmon leaf by the coupling technique of microwave-assisted extraction and membrane separation. The method comprises the following steps of: after the dried persimmon leaf is smashed, adding ethanol, and extracting at constant pressure and under the microwave environment; removing organic acid substances, such as chlorophyll, tannin, resin, reducing sugar and polysaccharide by the membrane separation technology; after the mixture is condensed, successively adding alkali and acid to process; and finally recrystallizing to obtain the persimmon leaf tartaric acid. The raw material adopted by the method disclosed by the invention is the natural persimmon leaf, no three wastes are generated, and the technology is simple and environment friendly. The method has the advantages of short extraction time, high yield, small impurity content and stable quality, and the obtained product persimmon leaf tartaric acid achieves the requirement for serving as the raw material of cosmetics, and the economic benefit is obvious.

The invention discloses a method for preparing a modified polymethyl methacrylate anticorrosive coating on a magnesium alloy surface. The method comprises the steps of treating the magnesium alloy surface; mixing a tetraethyl orthosilicate solution with a gamma-methacryloxy propyl trimethoxyl silane solution, adding a catalyst, and heating to form sol; adding an ethanol solution in which zirconium oxychloride is dissolved into the sol, continuously heating, dropwise adding a sodium hydroxide alkaline solution, and controlling the reaction rate to form SiO2-ZrO2 hybrid sol; adding methyl methacrylate in which AIBN is dissolved, N-N-dimethylformamide and a cerous nitrate aqueous solution, and heating in the water bath environment to prepare modified PMMA-SiO2-ZrO2 hybrid sol; and smearing the PMMA-SiO2-ZrO2 hybrid sol on the surface of a magnesium alloy surface base material through rotation, drying, keeping the temperature, and cooling to prepare the modified polymethyl methacrylate anticorrosive coating on the magnesium alloy surface. According to the method, different catalysts and chemical additives are added, so that the corrosion resistance of a sol gel film on the magnesium alloy surface is improved.

The invention discloses a method for preparing an aluminum-iron flocculant by red mud. According to the method, red mud is firstly washed to obtain washing liquid and a washing residue, the washing residue is mixed and stirred with a mixed leaching solvent of citric acid, tannic acid and malic acid at a mass ratio of 1: 3-7, a reaction temperature of 80-100 DEG C and a stirring intensity of 250-400r/min for 30-90min, after the end of the stirring, solid-liquid separation is carried out to obtain a titanium-rich material and acid leaching solution, the washing liquid is utilized to adjust the pH value of the acid leaching liquid to 7-9, a mixed polymeric medicament of triglycollamic acid and phytic acid in a liquid-solid mass ratio of 5-10: 1 is added for stirring and dissolution, after thestirring is completed, the mixture is aged at 50-80 DEG C for 5 to 10 hours, standing and ageing are carried out at room temperature for 24 to 48 hours, the aged upper liquid is discharged to obtaina milky polymeric aluminum-iron flocculant, and finally drying is carried out at 100-110 DEG C for 8 to 16 hours to obtain the aluminum-iron flocculant product with less than 0.2% of water-soluble impurities.

The present invention discloses a heteropolyacid ammonium salt catalyst and a preparation method thereof. The catalyst comprises an active component, auxiliary agents and a carrier, wherein the active component is a heteropolyacid ammonium salt, the auxiliary agents are nickel, phosphorus and vanadium, the carrier is an amorphous silicon-aluminum coated molecular sieve, the auxiliary agents comprise (calculated as the oxide) 3.0-10.0% of P2O5, 0.2-4.0% of V2O5 and 8-20% of NiO by adopting the weight of the carrier as the reference, the heteropolyacid ammonium salt content is 8-30% by adopting the weight of the catalyst as the reference, and the total content of the auxiliary agents and the carrier is 70-92% (calculated as the oxide). According to the present invention, the catalyst has advantages of high low-temperature activity, high selectivity, high carbon deposition resistance and improved stability, and is particularly suitable for the ethylene preparation reaction through dehydration by using the low-concentration ethanol aqueous solution as the raw material.

The invention discloses an anhydrous production method of DMMn (polyoxymethylene dimethyl ethers). The anhydrous production method comprises steps as follows: a substance containing hydrogen sulfate radicals is taken as a catalyst, at least dimethoxymethane and paraformaldehyde are taken as reaction raw materials, the catalyst and the raw materials are subjected to a reaction at the temperature of 70-150 DEG C and under the pressure of 0.1-8.0 MPa, and DMMn is prepared. Preferably, the catalyst accounts for 0.5wt%-30wt% of the total reaction materials, and further preferably, the catalyst accounts for 1wt%-10wt% of the total reaction materials. The protection process of DMMn adopts paraformaldehyde as an aldehyde source, the cost is low, meanwhile, low-cost hydrogen sulfate or supported hydrogen sulfate is taken as the catalyst, the catalyst has a good effect and is non-toxic and low in cost, and particularly, compared with strong acids such as sulfuric acid, hydrochloric acid and the like, low-cost hydrogen sulfate or supported hydrogen sulfate has relatively lower acidity, is in a solid state, has low corrosivity and can be recycled from a reaction system through simple filtration.