36results about How to "Control molar ratio" patented technology

The invention discloses a method for preparing a semi-aromatic polyamide. The method comprises the steps of adding aromatic dicarboxylic acid and aliphatic diamine containing 4 to 14 carbon atoms into a high-pressure autoclave, applying nitrogen pressure in the autoclave under a condition of water existence, rising the temperature so as to pre-polymerize, and then preparing high viscosity semi-aromatic polyamide resin by performing tackifying reaction on the pre-polymerized materials. The method of the invention prepares the semi-aromatic polyamide by applying nitrogen pressure, the diamine loss is avoided and the mole ratio of the dicarboxylic acid and the diamine can be accurately controlled so as to acquire the high viscosity semi-aromatic polyamide. The pre-polymerized material which has a viscosity eta ranged from 0.06 to 0.3 dl / g tested in 96% sulfuric acid at 25 DEG C by performing the pre-polymerization reaction is acquired. After the tackifying reaction is performed, the viscosity eta of the semi-aromatic aromatic polyamide is ranged from 0.8 to 2.5 dl / g, the melting point of the semi-aromatic aromatic polyamide is ranged from 270 to 330 DEG C, the content of the end carboxyl is ranged from 15 to 80 mol / t and the content of the end amino is ranged from 15 to 80 mol / t.

A method for reforming a diesel fuel with high efficiency under a same condition as that of gasoline or the like to continuously produce hydrogen with high selectivity and high yield is provided. By allowing three catalysts having different functions from one another to be in a composite state and, then, controlling a reforming reaction of the diesel fuel, the diesel fuel is reformed with high efficiency under a same condition as that of gasoline or the like and, accordingly, hydrogen can continuously be produced with high efficiency and high yield.

The invention discloses a preparation method of columnar hexagonal potassium titanate, which belongs to the field of the chemical industry. The method comprises the steps of: a, uniformly mixing a -100 mesh titaniferous containing material and a potassium containing material according to a molar ratio of TiO2:K2O=4-7; b, placing the material mixed uniformly in the step a in an environment at 1100-1300 DEG C for sintering for 1-4 hours for adequate reaction of the material; and c, quickly cooling the sintered material in the step b, then adequately dissociating the cooled material by water at a constant temperature of 60-80 DEG C, and finally filtering and drying to obtain a columnar hexagonal potassium titanate product. The method provided by the invention is simple in process flow, easy to operate, low in cost and high in yield, and the prepared columnar hexagonal potassium titanate is large in draw ratio and high in purity, and is suitable for industrial production.

The invention discloses a method for preparing a semi-aromatic nylon salt. The method is to make aromatic dibasic acid and aliphatic diamine subjected to neutralization reaction in an organic solvent, perform centrifugal separation, wash obtained deposit, and obtain the semi-aromatic nylon salt. The semi-aromatic nylon salt prepared by the method has high purity, and the method can accurately control the mol ratio of the dibasic acid to the diamine to be equal under the condition of polycondensation. The organic solvent selected by the method can dissolve the aromatic dibasic acid and the aliphatic diamine but can not dissolve the semi-aromatic nylon salt, so that the generated nylon salt can be easily separated and purified. Moreover, the solvent used for preparing the semi-aromatic nylon salt can be recycled.

A preparation method of small-grain low-silica-content X zeolite includes mixing silicon-containing compound, sodium hydroxide, water and sulfuric acid solution or water soluble sulfate, stirring and adding aluminum-containing compound to obtain gel, adding the directing agent to the gel to obtain the mixture with the molar composition of (2.5-5.0)Na2O:Al2O3:(2.4-3.0) SiO2:(0.5-2.0)SO4<2->:(80-200)H2O, standing and crystallizing at 80-120 DEG C for 0.5-3.0 hours, water washing, filtering and drying. The obtained X zeolite has a crystal grain of 0.2-1.2 Mum, the molar ratio of silica / alumina is 2.07-2.3, and the crystallinity is more than 95%.

The invention relates to semi-aromatic polyamide and a preparation method thereof. The semi-aromatic polyamide is prepared by: adding aromatic dicarboxylic acids and the fatty diamine with 4-14 carbon atoms to an organic solvent to undergo neutralization reaction to prepare high-purification salt; pre-polymerizing by taking the high-purification salt as the raw material with the existence of water; preparing the semi-aromatic polyamide by the further tackification reaction of the prepolymer. By using high-purification salt, the preparation method can accurately control the molar ratio of dicarboxylic acids and diamine, and avoid the loss of the diamine. By purifying monomers in the salifying process, the preparation method also improves the quality of the semi-aromatic polyamide and obtains the semi-aromatic polyamide with high inherent viscosity, high crystallinity, high melting point and good mechanical performance.

The invention discloses a method for preparing semi-aromatic polyamide. The method adopts low temperature of 170 DEG C to 190 DEG C for dehydration firstly, and then adopts a method for temperature-raising and prepolymerization to prepare the semi-aromatic polyamide, thus avoiding the loss of diamine and being capable of accurately controlling the molar ratio of the dicarboxylic acids and the diamine, obtaining the polyamide with high intrinsic viscosity and improving the quality of semi-aromatic polyamide. By the prepolymerization reaction, the prepolymer which is measured in 96 percent of sulphuric acid with the temperature of 25 DEG C and has the intrinsic viscosity Eta of 0.06 to 0.3dl / g can be obtained. After viscosifying reaction, the intrinsic viscosity Eta of the semi-aromatic polyamide is 0.8 to 2.5 dl / g and the melting point of the semi-aromatic polyamide is 270 to 330 DEG C; the content of terminal carboxyl group is 15 to 80 mol / t; and the content of amino-terminated group is 15 to 80 mol / t.

The present invention is good for complex cleaning and degreasing agent which can save energy, and can shorten the cleaning time and show good cleaning and degreasing proficiency without changing the systems being used, and impairing the raw materials. The present invention is also for cleaning and degreasing agent that maintains the best alkalinity and can be used according to each characteristics of process, without being restrained under the scope of available temperature. The present invention includes the surfactant and alkaline builder of the below formula 1: R-O-(CH2CH2O)m-H, formula 2, formula 3: R-Ph-O-(CH2CH2O)-m-H, and formula 4: R-Ph-SO3<->M<+>. Wherein, from 1 to formula 4 R is alkyl group of which carbon number is 3-19, Ph is phenyl group, m is 1.5-12 mol for formula 1 and 2, and 13-19 moles for formula 3, n is 2-15 mol, and M is counter ion.