47results about How to "Reduce waste acid" patented technology

The invention discloses a method for preparing 2-ethylanthraquinone by continuous 2-(4-alkylbenzoyl)benzoic acid ring-closing reaction, which comprises the following steps: mixing liquid 2-(4-alkylbenzoyl)benzoic acid and room-temperature concentrated sulfuric acid in a mixer in a mass-volume ratio of 1:1.5-1:2.5, wherein the mixing temperature is room temperature to 100 DEG C, and the retention time of the mixture in the mixer is 1-10 minutes; connecting the mixer with a stirring reactor, and carrying out ring-closing reaction, wherein the temperature of the stirring reactor is 100-140 DEG C, and the retention time of the reaction materials in the reactor is 5-30 minutes; and directly hydrolyzing the liquid after reaction, extracting, and distilling to obtain the 2-ethylanthraquinone. The detailed method is disclosed in the specification. The process is simple to operate and easy to control, lowers the labor intensity, improves the working environment, reduces the equipment investment, lowers the waste acid quantity, and enhances the product yield by 5-10% as compared with the existing production technique; and the product quality is good.

The invention discloses a wet flue gas desulfurization method comprising the steps: obtaining absorption liquid with sulphite by using an alkaline absorbing agent which is in contact with flue gas to absorb SO2 in the flue gas in a desulfurizing tower; reacting the obtained absorption liquid containing sulphite with sulphuric acid; transmitting the SO2 precipitated by the reaction to an acid preparation system to prepare the sulphuric acid; and obtaining a solid settling matter of sulphate by soil-liquid collecting reaction. The wet flue gas desulfurization method can use sulphuric acid in waste acid to treat the absorption liquid, shortens a treating process and saves a large amount of device investment and operation cost, and the SO2 absorbed from the flue gas enters the acid preparation system again, therefore, resources can be recycled.

The invention relates to 2-naphthalene sulfonic acid, 2-sodium naphthalene sulfonate and a preparation technology thereof. The technical proposal is as follows: naphthalene and a little amount of anhydrous sodium sulfate are added to a reactor containing sulfuric acid with the concentration of 98% according to the mol ratio of the naphthalene to sulfuric acid being 1:0.1-0.5, and heated while stirring until the naphthalene and the anhydrous sodium sulfate are completely dissolved; SO3 gas is fed into the reactor within 1-3h for sulfonation reaction at the temperature of 120-180 DEG C; and then at the temperature of 150-180 DEG C, the naphthalene and the SO3 in the mixture obtained from the sulfonation reaction are blown away by compressed nitrogen gas when the mixture is stirred, so as to prepare the 2-naphthalene sulfonic acid. In addition, the prepared 2-naphthalene sulfonic acid can be added to a neutralization pot, and sodium sulfite solution with the concentration of 5%-15% which is preheated to 80-90 DEG C is added to the neutralization pot by a measuring tank, so the 2-naphthalene sulfonic acid and sodium sulfite solution can have neutralization reaction; crystallization and separation are carried out to obtain the 2-sodium naphthalene sulfonate. The preparation technology has the advantages of full utilization of the existing resources, high naphthalene conversion rate, good product quality, little environmental pollution, low cost and high economic benefits.

The invention relates to an after-treatment clean process for purifying vat blue 66 dye. The clean process comprises the steps: levigating a vat blue 66 crude product, filtering the levigated vat blue 66 by adopting a 300-mesh sieve, adding he filtered vat blue 66 in a sulfuric acid concentrated solution, wherein the weight ratio of the vat blue 66 crude product and the sulfuric acid concentrated solution is 1: (13-15), and the concentration of the sulfuric acid concentrated solution is 70 to 75 percent by weight; heating the mixed solution to 70 to 90 DEG C, stirring and insulating the mixed solution for 4 to 6 hours, when the vat blue 66 crude product is stirred and insulated in the sulfuric acid concentrated solution, the color of the mixed solution is turned from dark blue to olivine, cooling the mixed solution to the temperature of 50 DEG C after the mixed solution is thermally insulated, stirring the mixed solution for 4 to 8 hours, filtering the mixed solution, washing filter cake by utilizing the70% to 75% sulfuric acid concentrated solution or the sulfuric acid solution which is identical in the concentration, adding water to the filter cake, pulping the filter cake, heating the pulp to the temperature of 80 DEG C, preserving the pump for 0.5 to 1 hour, and drying the filter cake at the temperature of 90 DEG C to obtain a vat blue 66 dye dry product. The sulfuric acid concentrated solution with the concentration of 70 to 75 percent is obtained by after-processing the sulfuric acid concentrated mother solution obtained by purifying the vat blue 66. The invention provides the after-treatment clean production process of the vat blue 66.

The invention relates to a mercury-free catalyst used for acetylene hydrochlorination for synthesizing vinyl chloride, and a preparation method and an application thereof. The preparation method comprises the following steps: 1, dissolving alkali metal salt and an amide solvent in water to prepare a mixed solution; 2, adding active carbon into the mixed solution obtained in step 1, and dipping the active carbon; and 3, filtering the active carbon obtained in step 2, draining the filtered active carbon, and heating and drying the drained active carbon to obtain the catalyst. The concentration of raw gas on the surface of the catalyst is increased through using the synergism of the alkali metal salt and the amide solvent and the adsorbing and dissolving ability of the amide solvent to raw materials comprising acetylene and hydrogen chloride, and the amide solvent is a high-polarity aprotic polar solvent, and has a polarization effect on reactants, so the reaction efficiency is further improved, the low temperature activity of the catalyst is high, and the selectivity and the stability are good.

The invention relates to a non-noble metal mercury-free catalyst for acetylene hydrochlorination reaction, a preparation method and application thereof. The preparation method comprises the steps of: 1) preparing a mixed solution of a copper salt, an ammonium salt and phosphoric acid, or a mixed solution of a copper salt, an ammonium salt and phosphate; 2) adding activated carbon into the mixed solution obtained in step 1 for soaking; 3) spin-drying the soaked activated carbon, and conducting heating and drying to obtain the catalyst. Through the synergistic effect of multiple components, the catalyst prepared by the method provided by the invention acquires good catalytic stability and high low-temperature activity, and under a reaction temperature of 130DEG C and the existing mercury catalyst running pressure condition and feeding intensity, more than 96% of conversion per pass and more than 99% of vinyl chloride selectivity can be obtained. As the technical conditions of the catalyst for acetylene hydrochlorination reaction are similar to those of the existing mercury catalyst, renovation of existing equipment is unnecessary, and the mercury catalyst can be replaced easily on the existing equipment.

The invention belongs to the field of chemical synthesis, and particularly relates to a method for preparing 2-alkylanthraquinone with a microchannel continuous reactor. The synthesis is carried out in a microchannel reactor, and the method comprises the following steps: (1) catalyzing phthalic anhydride and alkylbenzene by using AlCl3 as a catalyst, and performing a Friedel-Crafts acylation reaction to generate 2-(4-alkyl benzoyl) benzoic acid; and (2) continuously reacting the 2-(4-alkyl benzoyl) benzoic acid with concentrated sulfuric acid through a mixer I, a reactor I, a mixer II, a reactor II and a separation unit of the microchannel reactor to generate the 2-alkylanthraquinone in a closed loop mode. Compared with a traditional intermittent reaction, the microchannel reaction adoptedin the method has the advantages of relatively good microchannel airtightness, high safety, little pollution and simple operation; the product has a yield increased by 5-10 percent in comparison withthat of an existing production process, and has high quality.

The invention discloses a method for preparing ecabet sodium. The method disclosed by the invention is characterized by comprising the following steps of carrying out sulfonation reaction on dehydroabietic acid (formula III) as a starting material and fuming sulfuric acid to obtain 12-sulfonic dehydroabietic acid (formula II) and enabling the compound shown as the formula II and a sodium-forming agent to form a sodium salt in a solvent system at least containing water to obtain ecabet sodium. By virtue of the method disclosed by the invention, the deficiencies of the prior art are overcome and the method has the advantage of high sulfonation yield and high selectivity in sodium salt forming, simple operation, safety and environment friendliness and is suitable for industrial production.

The invention discloses a preparation method of ecabet sodium, which is characterized in that: the method of the invention uses dehydroabietic acid (formula III) as a starting material, and carries out sulfonation reaction with oleum to obtain 12-sulfonic acid Base dehydroabietic acid (formula II), the compound of formula II and a sodium forming agent form a sodium salt in at least an aqueous solvent system to obtain ecabet sodium. The method of the invention overcomes the disadvantages of the prior art, and has the advantages of high sulfonation yield, high selectivity for sodium salt formation, simple operation, safety and environmental protection, and is suitable for industrial production.

The invention relates to a system for preparing liquid SO2 from concentrated waste acid, belonging to the fields of waste acid treatment and liquid SO2 production. Sulfur is used as a reducer to reduce the concentrated waste acid to prepare SO2 gas, and the unreacted high-solid-content waste acid is gasified and decomposed in an inert atmosphere, thereby recovering the sulfur element in the waste acid and separating the solid-phase slag in the waste acid; and the prepared concentrated SO2 gas is dehydrated and dried, and is subjected to pressure cooling separation to obtain the liquid SO2. The system for preparing liquid SO2 from concentrated waste acid comprises a temperature-control gasification and decomposition system, an oxidation-reduction reaction system, a heat recovery system, a sulfur melting system, a dehydration and drying system and a compression separation system. By adding the sulfur to initiate the oxidation-reduction reaction, the amount of waste acid entering the gasification chamber is greatly lowered, thereby effectively lowering the heat consumption of gasification; the SO2 yield is greatly enhanced, and the SO2 concentration is high; the energy source is sufficiently recovered, so the energy consumption is low; and the system has the advantages of small pollution and no waste gas emission.

The present invention belongs to the field of fined chemical intermediate synthesizing technology, and is process of preparing 4-amino-3-nitro phenol. The process of preparing 4-amino-3-nitro phenol includes the following three steps: acetylation of p-aminophenol as material with acetic anhydride, the subsequent nitration with nitric acid, and final hydrolysis of 4-acetoxy-2-acetamino nitrobenzenewith sodium hydroxide. The present invention has simple operation and low cost.

The invention relates to a method and device for deep demethanolization of C4. The demethanolization treatment of C4 extracted from the top of the azeotropic distillation tower is divided into three steps: firstly, the pre-distribution extraction of C4 is carried out by using microphase distribution technology; The C4 and the extract after the final extraction fully enter the modular deep separation device for deep separation of C4 and the extract; the C4 after demethanolization enters the subsequent production device, and the extract returns to the methanol recovery tower for further extraction. Recycle. The present invention also provides a set of devices for realizing the method, including an extraction device and a separation device; the extraction device is divided into a microphase disperser and a micro-swirl flow extraction device; the separation device is a coalescence separation module and a corrugated plate enhanced sedimentation, water bag, Boundary meter and several other parts. The method of the invention has high processing speed and high efficiency, and the methanol content in the treated C4 is not more than 5 ppm, thereby improving the performance of the C4 follow-up deep processing device.

The invention belongs to a preparation process of white carbon black, in particular to a process for producing precipitated white carbon black from silicon tetrachloride. Add silicon tetrachloride to the hydrochloric acid aqueous solution with a mass concentration of 29-33% containing a dispersant, control the temperature at 28-45°C to react to generate silica sol and hydrogen chloride gas, and the silica sol will form colloidal White flocculent precipitate, the precipitate is separated by filtration, washed, granulated and dried to obtain precipitated white carbon black. The present invention has short process flow, relatively simple production equipment and process control, and easy-to-obtain raw materials; silicon tetrachloride is effectively utilized, and the product hydrogen chloride is completely recovered, thereby reducing treatment costs, reducing the amount of waste acid, and reducing environmental pollution; The production cost is low, the application is extensive, and the market capacity is large.

The invention relates to a system for preparing liquid SO2 from concentrated waste acid, belonging to the fields of waste acid treatment and liquid SO2 production. Sulfur is used as a reducer to reduce the concentrated waste acid to prepare SO2 gas, and the unreacted high-solid-content waste acid is gasified and decomposed in an inert atmosphere, thereby recovering the sulfur element in the waste acid and separating the solid-phase slag in the waste acid; and the prepared concentrated SO2 gas is dehydrated and dried, and is subjected to pressure cooling separation to obtain the liquid SO2. The system for preparing liquid SO2 from concentrated waste acid comprises a temperature-control gasification and decomposition system, an oxidation-reduction reaction system, a heat recovery system, a sulfur melting system, a dehydration and drying system and a compression separation system. By adding the sulfur to initiate the oxidation-reduction reaction, the amount of waste acid entering the gasification chamber is greatly lowered, thereby effectively lowering the heat consumption of gasification; the SO2 yield is greatly enhanced, and the SO2 concentration is high; the energy source is sufficiently recovered, so the energy consumption is low; and the system has the advantages of small pollution and no waste gas emission.

The invention discloses a method for decreasing the waste acid content in titanium dioxide production. Sulfur trioxide and 55% sulfuric acid are adopted to be premixed with titanium concentrate for an acidolysis reaction in the rutile-type titanium dioxide production process through a sulfuric acid method, and then the method for decreasing the waste acid content in titanium dioxide production is achieved.

The invention discloses a preparation technology for a 2-sulfonaphtine mixture. The preparation technology comprises the following steps: enabling 2-naphthol to be subjected to sulfonation in sulfuricacid of which the mass fraction is 98-100% and fuming sulphuric acid of which the mass fraction of the sulfuric acid is 105%, to obtain sulfonation liquid of a mixture containing 2-hydroxyl-6,8-naphthalene disulfonic acid, 2-hydroxyl-3,6-naphthalene disulfonic acid and 2-naphthol monosulfonic acid, adding ammonia water to the sulfonation liquid for regulating an ammonia value, adding ammonium sulfite for catalytic-aminolysis, and adding dilute sulphuric acid for acidizing, to obtain a mixture of 2-amino-6,8-naphthalene disulfonic acid, 2-amino-3,6-naphthalene disulfonic acid and 2-amino monosulfonic acid, namely the 2-sulfonaphtine mixture. The mixture is capable of sulfonating in 115% of the fuming sulphuric acid so as to obtain 2-amino-3,6,8-naphthalene trisulfonic acid. The preparationtechnology is capable of greatly improving the utilization ratio of the 2-naphthol.