90 results about "Insoluble residue" patented technology

The invention discloses a recovery method for a cathode material of a waste lithium iron phosphate battery. The recovery method comprises the following steps: firstly, placing a positive plate obtained through disassembly of the waste lithium iron phosphate battery in an ultrasonic machine containing a dilute alkali liquor to be processed, so that a lithium iron phosphate material is separated from an aluminum foil; then, drying the lithium iron phosphate material, after that, performing acid leaching under a normal-temperature condition, and controlling the quantity of an acid solution to ensure that the pH of the solution is 2.5-6.5 after finish of a reaction and iron exists in insoluble residues in the format of iron phosphate, wherein the leaching rate of lithium is more than 97% and the leaching rate of iron is less than 0.1%; and performing filtering to obtain a filtrate and insoluble iron phosphate, performing heat treatment on the insoluble residues to remove organics so as toobtain ferric phosphate, and after purification and enrichment of the filtrate, adding trisodium phosphate for a reaction to obtain lithium phosphate. In the whole recovery process, the yields of lithium and iron are respectively 96% and 99.5%. The recovery method has the advantages that used equipment is simple, the technological process is short, and valuable raw materials are efficiently recovered.

The invention relates to a temperature resistant water-base fracturing fluid thickening agent and a method for preparing the same. The thickening agent consists of acrylamide, 2-acrylamido-2-methyl-1-propane sulfonic acid, N-vinyl pyrrolidone, complexing agent EDTA, chain transfer agent, sodium hydroxide aqueous solution and deionized water. The thickening agent is prepared by copolymerizing industrial raw materials of the acrylamide, the 2-acrylamido-2-methyl-1-propane sulfonic acid and the N-vinyl pyrrolidone in a reactor provided with a stirrer and a thermometer. The preparation method is simple. The prepared temperature resistant water-base fracturing fluid thickening agent does not contain insoluble residues, and the thickening agent of which the mass percentage is 0.5 percent is cut continuously for 30 minutes under the condition of 170S and 95 DEG C so that the viscosity is kept over 65 percent.

A process for extracting and recovering polyhydroxyalkanoates (PHAs) from cellular biomass comprising the steps of: extracting the polyhydroxyalkanoate with at least one non-halogenated solvent which is non-aggressive to the environment; heating the cellular biomass, in order to form a suspension comprising PHA solvent with the dissolved PHA and insoluble residues; recovering the solvent enriched with PHA; injecting the PHA-enriched solvent in a vapor flow in order to rapidly promote the complete precipitation of PHA in water, while processing the solvent evaporation; depleting the residual solvent; separating the purified PHA particles from the suspension and drying them.