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122results about "Hydrazine" patented technology

Separation of salt and alkali from waste salt and alkali residue in production of hydrazine hydrate and technique of cyclic utilization

This invention describes a process for the recovery and recycle of industrial waste solids, especially the salt-alkali separation and recycle of the waste salt-alkali solids from the manufacturing of hydrated nitriles. This invention uses water, mother liquid and sodium bicarbonate to wash the waste salt-alkali solids from the manufacturing of hydrated nitriles, so that Na2CO3 and NaOH in the waste salt-alkali solids are washed into the solution. The washing solution is then cooled to 0-5deg.C, and filtrated and separated to obtain solid sodium carbonate decahydrate, which can be commercialized after washing. The mother liquid, after separating the solid alkali, is directed to the next process for washing the waste salt-alkali solids without discharge. During the circulatory washing of the waste salt-alkali solids, the table salt keeps in the solid state. After centrifugal separation, the table salt containing 3% of alkali can be obtained and used for sodium carbonate industry. The said table salt NaCl, after washing and separation to remove a small amount of hydrazine and amine, can be used for chlorine-alkali industry. Chlorine Cl2 and sodium hydroxide NaOH are raw materials for sodium hypochlorite NaClO, which is a raw material for producing hydrazine hydrate. In addition, sodium hydroxide is directly involved in the reaction for producing hydrazine hydrate N2H4íñH2O, thus constituting an internal recycling system of a manufacturing plant without discharging, which not only is environmentally friendly but also reduces transportation load and production cost. This invention describes a rational process for large-scale hydrazine hydrate manufacturing plants.
Owner:陈大元

Method for recycling organic solvents of wastewater generated in synthesis of hydrazine hydrate by ketazine method

The invention relates to a method for extracting organic solvents and hydrazine sulfate from wastewater generated in synthesis of hydrazine hydrate by a ketazine method. The method comprises the following steps: converting, purifying hydrazine sulfate, rectifying and preparing isopropanol, wherein the step of conversion comprises the following steps: slowly dropping sulfuric acid into a hydrazine hydrate wastewater solution under the condition of 0-15 DEG C so as to precipitate and separate out hydrazine sulfate from the solution, and performing centrifugal filtration to obtain a crude hydrazine sulfate product; the step of purifying hydrazine sulfate comprises the following steps: filtering the crude hydrazine sulfate product, washing for 2-3 times by using cold water, and performing centrifugal filtration and drying crystallization so as to obtain a pure hydrazine sulfate product; the step of rectifying comprises the following steps: collecting filtrate and a washing liquid, feeding into a rectifying tower, rectifying when the tower top temperature is 55-56 DEG C so as to collect a pure acetone product, and rectifying when the tower top temperature is 80-82 DEG C so as to collect binary azeotrope of isopropanol-water; the step of preparing isopropanol comprises the following steps: dehydrating the binary azeotrope of isopropanol-water by using caustic soda flakes, and subsequently distilling, thereby obtaining a pure isopropanol product.
Owner:潍坊蓝海环境保护有限公司

Method for recovering hydrazine sulfate and chromium hydroxide from chromium-containing waste acid

The invention discloses a method for recovering hydrazine sulfate and chromium hydroxide from chromium-containing waste acid, which comprises the following steps of: diluting hydrazine hydrate, slowly adding waste acid into the hydrazine hydrate with stirring, ensuring an acid adding end point when the pH of feed liquid is 0.8-1.2, and reacting hexavalent chromium in the waste acid with the hydrazine hydrate to reduce the hexavalent chromium into trivalent chromium and generate indissoluble hydrazine sulfate crystals; performing solid-liquid separation to obtain crude hydrazine sulfate and acidic chromium sulfate solution; adding alkali into acidic chromium sulfate solution for neutralization to obtain a chromium hydroxide precipitate, performing solid-liquid separation, washing with water, and drying to obtain an industrial product chromium hydroxide meeting quality requirement; and treating wastewater subjected to solid-liquid separation and washing in a wastewater treatment device for up-to-standard emission. The method is easy to operate, and the chromium-containing waste acid is treated for up-to-standard emission; meanwhile, the hydrazine sulfate and chromium hydroxide are recovered, so that the resources are reasonably utilized and the economic benefit is obvious.
Owner:NANJING UNIV

Method for gas stripping and separating hydrazine from hydrazine-containing solution using acetone and use thereof

ActiveCN101311107ASolving the Condensation Wastewater ProblemHydrazine preparationHydrazineGas phaseHydrazine compound
The invention relates to a method for obtaining pure hydrazine hydrate by isolating and purifying from solution containing hydrazine. The preparation method is that gas-phase acetone and the hydrazine which is contained in oxidation liquid are directly reacted and stripped under the boiling condition; or liquid-phase acetone and the solution are reacted first and then gas stripping is carried out, after the solution is hydrolyzed, the pure hydrazine hydrate is obtained; and the obtained product is sent into a general hydrolyzing tower, in which hydrolysis is carried out to produce the pure hydrazine hydrate solution, and acetone produced by the hydrolysis is sent back to a system for recycling, wherein, the mole ratio of the acetone and the hydrazine is 2 to 3.6 and the reaction temperature is 100 DEG C to 130 DEG C. By adopting the invention, the hydrazine produced by urea-chlorine method can be stripped by acetone azine (CH3)2C=N-N=C-(CH3)2, which causes the recycling of the inorganic materials such as sodium carbonate, sodium chloride, and the like, in the solution to be possible, thereby thoroughly solving the problem of waste water condensation of the ADC processing technique in the urea-chlorine method.
Owner:EAST CHINA UNIV OF SCI & TECH +2

Process for producing biurea

The invention relates to a preparation method of biurea, which includes the following steps: A) a crude hydrazine hydrate liquor is evaporated through an evaporator to get a salt-free hydrazine hydrate liquor and a solid saline-alkaline; B) the ejected salt and alkali are dissolved and reacted with a magnesium chloride liquor, a sulfate of zinc and a chloride liquor to generate a precipitation of basic magnesium carbonate or a basic zinc carbonate and get the basic magnesium carbonate or the basic zinc carbonate after filtering and washing; C) an evaporated hydrazine hydrate dissolves urea, which is added with sulfate or pumped with an anhydrous hydrogen chloride to carry out a condensation reaction to generate the biurea and an ammonium sulfate or an ammonium chloride; D) the mother liquor containing the ammonium sulfate or the ammonium chloride gained through separation can acquire the ammonium sulfate or the ammonium chloride through concentration. The beneficial effects of the invention are that the invention thoroughly solves the problem of serious ammonia nitrogen pollution during the production of biurea and all the byproducts are reasonably reused and recycled; besides, the evaporation efficiency is high, which saves the amount of hydrochloride or sulfate and can avoid the overflow of raw materials caused by the large amount of bubbles in the process of neutralization.
Owner:HANGZHOU HI TECH FINE CHEM

Method for removing sodium carbonate from hydrazine hydrate crude solution

The invention discloses a method for removing sodium carbonate from a hydrazine hydrate crude solution. The method comprises the following steps: 1, a urea solution is mixed with sodium hypochlorite, wherein a molar ratio of the urea solution to sodium hypochlorite is 1-2, such that the crude solution obtained by a reaction does not contain sodium hydroxide; 2, a chloride is added into the hydrazine hydrate crude solution; and centrifugal separation is carried out, such that poorly soluble carbonate is separated; 3, the hydrazine hydrate solution with sodium carbonate removed is subjected to membrane filtration, such that cations in the solution are removed. With the method, sodium carbonate in the hydrazine hydrate crude solution is thoroughly removed. The produced poorly soluble carbonate can be directly sold after certain treatments, and can be subjected to a reaction with hydrochloric acid recovered from an ADC process for producing chloride for recycling. When the sodium-carbonate-removed hydrazine hydrate solution is used in a biurea production process, acidic substance addition can be greatly reduced. When the sodium-carbonate-removed hydrazine hydrate solution is used in a hydrazine hydrate production process through evaporation and rectification, evaporation and rectification continuous production is facilitated.
Owner:HANGZHOU HI TECH FINE CHEM

Method for achieving ammonium chloride cooperative production through ADC foaming agent wastewater by means of total-hydrochloric acid pure hydrazine hydrate condensation

InactiveCN105417510AUnique methodSolve difficult governance problemsHydrazineAlkali metal carbonatesFoaming agentProcess engineering
The invention relates to ADC foaming agent production technology improvement and waste water recycling, in particular to a method for achieving ammonium chloride cooperative production through ADC foaming agent wastewater by means of total-hydrochloric acid pure hydrazine hydrate condensation. The method comprises the steps that vapor containing hydrazine is prepared from a hydrazine hydrate coarse solution at first, then the vapor containing hydrazine is rectified through a rectifying tower to obtain pure hydrazine needed for producing ADC, crystallized sodium chloride and sodium carbonate particles in the evaporation process are deposited at the bottom of an evaporator, separated through a centrifugal machine and then fed to sodium carbonate for electrolysis, urea and hydrochloric acid produced through oxidation in follow-up working procedures are added into the hydrazine hydrate obtained after rectification to be used for production of an ADC foaming agent, the obtained waste water only contains ammonium chloride, water in the ammonium chloride solution is continuously evaporated through heating, and an ammonium chloride crystal is separated out after supersaturation is reached; the method is unique, the ADC foaming agent production wastewater is converted into the water solution only containing ammonium chloride, follow-up treatment is more simple, and the obtained product is higher in value.
Owner:NINGXIA RISHNEG HIGH NEW IND CO LTD

Preparation method for continuously preparing tert-butylhydrazine hydrochloride

The invention discloses a method for continuously preparing tert-butylhydrazine hydrochloride by using a micro-channel reactor. The method comprises the steps of 1, carrying out primary reaction mixing on hydrazine hydrate with the mass concentration of 40-80% and hydrochloric acid with the concentration of 25-36% in the micro-channel reactor to obtain a hydrazine hydrochloride solution; 2, mixingthe hydrazine hydrochloride solution with a tert-butyl alcohol solution in the micro-channel reactor for later use; and 3, carrying out a secondary reaction on the material mixed in the step 2 to obtain a product aqueous solution, continuously concentrating the product aqueous solution to achieve a certain concentration, carrying out cooling crystallization, filtering, and drying to obtain the tert-butylhydrazine hydrochloride. According to the method, the reaction rate and the raw material utilization rate are increased, the side reaction for producing the olefin compounds through tert-butylalcohol dehydration is avoided, the reaction is easy to control, the production period is short, emission of three wastes is little, the total yield can reach 85% or above, and the automation degreeof the reaction process is high.
Owner:SHANGHAI NO 4 REAGENT & H V CHEM

Method for implementing co-production of ammonium sulfate from ADC foaming agent wastewater by extracting hydrazine hydrate

The invention relates to a method for coproducing ammonium sulfate from wastewater, in particular to a method for implementing co-production of ammonium sulfate from ADC foaming agent wastewater by extracting hydrazine hydrate. The method comprises the following steps that after being preheated step by step by condensate water with each effect, hydrazine hydrate coarse solution enters evaporator with each effect in parallel to be heated and evaporated; after settling and being pulped, saline-alkali pulp discharged by evaporator with each effect through a pipeline is subjected to centrifugal dewatering to obtain saline-alkali slags; centrifugal mother liquid is settled to obtain clear liquid returned to a hydrazine hydrate coarse solution storage tank; the saline-alkali slags are pulped by saturated liquid and are respectively made into salt pulp and alkali pulp by multiple gravity fractionations; and the salt pulp and alkali pulp are respectively subjected to centrifugal dewatering to obtain salt slags and alkali slags. According to the invention, the process is unique and the ADC foaming agent production wastewater only contains a mass of ammonium sulfate, so that the aim of treating the wastewater pollution of an ADC foaming agent is fulfilled.
Owner:NINGXIA RISHNEG HIGH NEW IND CO LTD

Method for preparing acetylene, ethylene, ethanol and ethylene glycol and coproducing hydrazine hydrate, benzene and derivatives of hydrazine hydrate and benzene by using CO or CO2

The invention relates to a new technical route or technical approach for synthesizing acetylene, ethylene, ethanol and ethylene glycol and coproducing hydrazine hydrate, benzene and derivatives of hydrazine hydrate and benzene by using CO or CO2 according to a reaction which is derived from the rule of a synthetic reaction discovered recently: a tandem substitution rearrangement reaction (TSRE reaction for short) of elementary chemistry, namely the deoxygenation homocoupling reaction (TSRE coupling for short) of CO2 and CO; the technical route or technical approach can be used for directly synthesizing the products such as acetylene, ethylene, ethanol, ethylene glycol, hydrazine hydrate, benzene and so on with the CO or CO2 as the raw material; compared with the traditional technical route or technical approach for preparing the products, the technical route or technical approach provided by the invention does not require petroleum resources, and is mild in synthesis conditions, and is generally implemented under the conditions of low pressure and normal temperature; as a result, the preparation cost is reduced by more than 40% to 80%; no three wastes are generated in the preparation process; and therefore, the new technical route or technical approach is completely up to the standards of the clean production process and more suitable for the development of large-scale industrial and commercial techniques.
Owner:李坚
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