46results about How to "Low Sulfate Content" patented technology

The invention provides a method for preparing industrial-grade phosphoric acid by an emulsification, extraction and purification wet method. The method comprises the sequential process steps of primary de-coloring, emulsification and extraction, emulsification and washing, emulsification and reverse extraction, concentration, dearsenification and heavy metal removing, secondary deep de-coloring and concentration adjustment. A method for food-grade phosphoric acid by the emulsification, extraction and purification wet method comprises the sequential process steps of primary de-coloring, emulsification and extraction, emulsification and washing, emulsification and reverse extraction, concentration, dearsenification and heavy metal removing, secondary deep de-coloring, defluorination and concentration adjustment. The emulsification and extraction step comprises the following steps of: agitating at normal pressure and at a temperature of 50-60 DEG C for 10-60 seconds at the speed of 500-3000 r / min; and agitating at the normal pressure and at the temperature of 50-60 DEG C for 60-240 seconds at the speed of 120-220 r / min; the emulsification and washing step comprises the following steps of: agitating at the normal pressure and at the temperature of 50-60 DEG C for 10-60 seconds at the speed of 500-3000 r / min; and agitating at the normal pressure and at the temperature of 50-60 DEG C for 60-240 seconds at the speed of 120-220 r / min; and the emulsification and reverse extraction step comprises the following steps of: agitating at the normal pressure and at the temperature of 50-60 DEG C for 10-60 seconds at the speed of 500-3000 r / min; and agitating at the normal pressure and at the temperature of 50-60 DEG C for 60-240 seconds at the speed of 120-220 r / min.

The invention discloses a method for reducing the content of sulfate radicals in dihydric dilute phosphoric acid, which is characterized in that a desulfurizer is added to wet-process phosphoric acid extraction slurry, mixed and stirred, and mixed and reacted at 60-80°C for 5-30 minutes. Then the mixed slurry is sent to the filter of the phosphoric acid extraction device for filtration, and the diluted phosphoric acid with a sulfate mass percentage content of less than 1.2% is obtained by filtration; The mass ratio of sulfate radicals in the medium is 0.35-0.50:1. The present invention solves the problem of high sulfate content in the dilute phosphoric acid of the dihydrate method, and is beneficial to the use of the dihydrate method phosphoric acid in the production of high-nutrient ammonium phosphate fertilizer, feed grade phosphate, industrial grade ammonium phosphate and phosphoric acid purification products. Simple, short desulfurization reaction time, good desulfurization effect and low desulfurization cost.

The invention provides a method for producing sodium isophthalate-5-sulfonate diethylene glycol ester (SIPE) from the three-monomer process wastewater concentrate, which is characterized in that: the method includes dissolving, filtering, and SIPE synthesis. The SIPE solution prepared by the present invention has low sulfate content, and the sulfate content is 156.48-231.47ppm; the SIPE solution prepared by the present invention has good appearance, high purity, and less impurity content; the appearance is a slightly yellow transparent liquid, and the purity is 94.33-95.1 % (LC), DEG content is 0.12‑0.28%. The reaction temperature of the present invention is low, the reaction temperatures of the first stage and the second stage are respectively 170-180°C and 185-195°C, and the synthesis reaction time is 4.8-5.2h.

The invention discloses an impurity removal method of electrolytic manganese dioxide. The method comprises the following steps: crushing manganese dioxide falling from anodes, adding dilute sulfuric acid and nitric acid, mixing evenly, sintering the mixture at 200-250 DEG C for 40-50 minutes, cooling the mixture to 70-80 DEG C at a speed of 5-10 DEG C / min, filtering, pickling manganese dioxide left after the filtering treatment by using the dilute sulfuric acid, mixing the pickled manganese dioxide with a small amount of water, heating to 50-70 DEG C through microwave, treating with 30-40 KHz ultrasonic wave for 10-20 minutes, drying, and treating the dry manganese dioxide in a dry magnetic separator for 0.5-2 hours to obtain refined manganese dioxide. The method can be used for not only effectively removing such impurities in the electrolytic manganese dioxide as low-valent manganese oxide, lead, copper, sulfate radical, molybdenum and iron, but also improving the discharge performance of the electrolytic manganese dioxide.

The invention discloses a preparation method of low-solidification-temperature agarose. The preparation method includes the following steps that 1, agarose is dissolved in deionized water to prepare an agarose solution; 2, the agarose solution is naturally cooled to 60-83 DEG C, and then a sodium hydroxide solution of sodium borohydride is added into the agarose solution for a reduction reaction; 3, a sodium hydroxide solution is added for alkalization treatment; 4, rapid cooling is carried out, and oxirane is slowly dripped with stirring for a derivatization reaction; 5, heating is carried out, and an acetic acid solution is dripped with stirring to regulate the pH value of the solution; 6, hot isopropanol is added with stirring for alcohol precipitation fractionation; 7, filtering, smashing and washing are carried out several times to obtain a filter cake; 8, after drying, smashing and screening, low-solidification-temperature agarose is obtained. According to the preparation method, common agarose is subjected to chemical modification and fractionation purification, and prepared agarose has the advantages of being low in solidification temperature and melting temperature, high in jelly strength and the like and is an ideal biological material for DNA separation and extraction.

The invention discloses a method for separating and preparing high-quality agarose from agar in combination with a flocculation method. The method comprises the following steps: preparing an agar solution of a certain concentration, heating and dissolving; preparing a solution of polyaluminum chloride and polyacrylamide with a suitable concentration; keeping warm in a water bath at 40-100°C for a period of time; Add a certain volume of polyaluminum chloride solution and stir for a certain period of time; add a certain volume of polyacrylamide solution and stir for a certain period of time in the above reaction solution; filter, remove the filter residue, and collect the filtrate; The gel was freeze-dehydrated, washed, dried, and crushed to obtain agarose. The preparation method used in the present invention is to remove sulfur agar and pigment in the agarose solution through the combined use of polyaluminum chloride inorganic cationic flocculant and polyacrylamide cationic flocculant, which has good gel performance and can reach the fields of molecular biology and the like. Requirements for high-quality agarose.

The invention discloses a phosphoric acid desulphurization method used in a feed grade calcium hydrogen phosphate production technology. The method comprises the following steps: 1, adding phosphate rocks to phosphoric acid to carry out pre-extraction and desulphurization; 2, conveying a slurry obtained after a complete reaction to a cyclone, and carrying out solid-liquid separation; 3, allowing cyclone underflow to enter an extraction tank after the solid-liquid separation, extracting the cyclone underflow, allowing an overflowing slurry to enter a settlement device, and settling the overflowing slurry; and 4, allowing a clear liquid obtained after settlement to enter a defluorination process, allowing a thick slurry obtained after settlement to enter the extraction tank, extracting the thick slurry, and circulating step 2 to step 4. The method has the advantages of ingenious design, stable thick slurry volume and denseness, no influences of re-extraction of the desulphurized thick slurry on the slurry filtering effect, low cost, satisfactory improvement of the contradiction of phosphoric acid desulphurization and the filtering effect, and realization of depth desulphurization.