35results about "Ammonium sulfides/polysulfides" patented technology

This invention concerns processes for converting oxygenates to olefins that include a step of pretreating catalyst used in the conversion reaction. A fresh or regenerated metalloaluminophosphate molecular sieve, which is low in carbon content, is pretreated with an aldehyde. The aldehyde forms a hydrocarbon co-catalyst within the pore structure of the molecular sieve, and the pretreated molecular sieve containing the co-catalyst is used to convert oxygenate to an olefin product.

A ternary V—Ti—P mixed oxide is shown to catalytically dehydrate 2-methyl-tetrahydrofuran in high conversion to give piperylene, in good yield. Volatile products collected from this reaction contain piperylene in concentrations as high as 80 percent by weight. Dehydration of glycerol to acrolein in high conversion and moderate selectivity is also demonstrated. The catalyst is also shown to dehydrate other alcohols and ether substrates. The catalyst is resistant to deactivation and maintains activity between runs.

The invention discloses a method for preparing precipitated barium sulfate by utilizing titanium white waste acid, belonging to the technical field of comprehensive utilization of titanium white wasteacid and preparation of barium sulfate. The method comprises the following steps of adding ammonium hydroxide to neutralize with titanium white waste acid firstly, then generating ammonium sulfate, and controlling a systemic pH to separate out photodegredation sediment; then adding the ammonium hydroxide continuously, and controlling the pH to separate out ferrous hydroxide sediment; then addinghydrogen peroxide in proportion, oxidating residual Fe2<+> into Fe3<+>, and adjusting the pH to separate out ferric hydroxide sediment; condensing an ammonium sulfate solution, then replacing a mirabilite solution in a traditional precipitated barium sulfate production process, enabling the ammonium sulfate solution to generate replacement reaction with a barium sulfide solution, and washing, drying and smashing to prepare a precipitated barium sulfate product. According to the method, after neutralizing the titanium white waste acid with the ammonium hydroxide and performing purification andimpurity removal, a traditional sodium sulfate solution is replaced for producing the precipitated barium sulfate, meanwhile, recycled photodegredation sediment can be further used for titanium dioxide production, not only are resources saved, but also waste can be recycled, and the waste acid treatment costs of titanium dioxide plants and environment protection pressure are reduced.

The invention relates to a sub-micron spherical strontium sulfate, and preparation and application thereof. The method comprises the following steps: 1. carrying out solid-liquid separation on an SrS solution of which the concentration is higher than 90 g / L and the temperature is greater than or equal to 95 DEG C; 2. regulating the concentration of the SrS solution obtained in the step 1 to 40-45 g / L, and regulating the temperature to 55-60 DEG C (preferably 57 DEG C); 3. while stirring, adding equal mol of (NH4)2SO4 solution (the concentration is 140-160 g / L, preferably 150 g / L) into the SrS solution obtained in the step 2, controlling the reaction time within the range of 10-12 minutes, and filtering to obtain a filter cake; and 4. coating calcium stearate, which accounts for 0.8-1.5 wt% of the SrSO4, on the filter cake at 90-95 DEG C, thereby obtaining the sub-micron spherical strontium sulfate product. The invention overcomes the defect that the existing strontium sulfate has high electric conductivity and can not be used in a PCB (printed circuit board) paper substrate as a filler. The sub-micron spherical strontium sulfate has the advantages high purity and favorable whiteness, has lower electric conductivity through the treatment of the coating agent, improves the dispersity in the organic system, and satisfies the application as a filler in a paper PCB.

The invention relates to a method for harmless treatment of n-butylthiophosphoric triamide hazardous waste, comprising the following steps: (1) adding a degradation conversion agent into a reaction kettle, and adding n-butylthiophosphoric triamide hazardous waste , stirred and heated to obtain ammonia gas and distillation condensate respectively; ammonia gas is passed into the absorption tower to be absorbed by water; The liquid is refined below the boiling point of n-butylamine, the output liquid at the top of the tower is n-butylamine, and the liquid at the bottom of the tower is returned to the reactor as a degradation conversion agent; Stir and react at ~55°C for 1~2h to obtain hydrogen sulfide; hydrogen sulfide is passed into the ammonia absorption tower for chemical absorption to obtain ammonium sulfide solution with a concentration of 16~20%; the ammonium sulfide solution is centrifuged to obtain filtrate and filter residue respectively. Calcium phosphate; the filtrate is returned to the reactor as a desulfurization conversion agent. The invention does not discharge three wastes and can achieve full resource recovery.

The invention provides a low-grade complex nickel-molybdenum ore cleaning pretreatment method. Nickel-molybdenum ores, a chlorinating agent and water are uniformly mixed at the specific proportions and then subjected to pelleting, material balls after being pelleted are directly placed in a volatilization furnace without being dried, and chlorination volatilization and smelting are conducted undera specific warming mechanism. Products such as molybdenum chloride, zinc chloride, arsenic chloride, nickel chloride, ammonium sulfide and ammonium sulfate in the smoke generated by volatilization are recycled respectively in a smoke collection device. The method can treat various kinds of low-grade and complex nickel-molybdenum ores, molybdenum, zinc, nickel and other valuable components in thenickel-molybdenum ores can be separated in a one-step mode, sulphur can be recycled in the forms of ammonium sulfide, ammonium sulfate and the like, and emission of low-concentration SO2 is avoided. Meanwhile, harmful components such as concomitant arsenic in the nickel-molybdenum ores can be deeply volatilized and removed, and the volatile residue obtained through volatilization is harmless to the environment. Compared with an existing nickel-molybdenum ore treatment method, the method has the advantages that the energy consumption is low, the efficiency is high, and the clean and environment-friendly effects are achieved.

A crystallization column and a crystallization method. The crystallization column comprises an upper head (1), a tower body (2) and a lower head (3), wherein a crystallization section (11) is provided with a tray (14); and the tray (14) comprises a tray plate (15) and a plurality of lower crystallization members (17). The top end of the lower crystallization member (17) can form a movable connection with the tray plate (15), so that the two adjacent lower crystallizing members (17) are capable of oscillating collisions. The tray (14) may also comprise a plurality of upper crystallization members (21) extending upwardly from the upper surface of the tray plate (15).

The aqueous composition comprises at least one oxidizable sulfur-based compound. The concentrated extract of the aqueous composition comprises a gas chromatography / mass spectrometry detectable amount of a contaminating refinery hydrocarbon, but the aqueous composition is free of refinery odor when stored at room temperature and 60% relative humidity for at least 24 hours. The aqueous composition is prepared from a gas stream obtained from petroleum refining processes, coke ovens and the like, the gas stream comprising at least about 4 mol%, more particularly about 15 mol% of hydrogen sulfide (H2S) and / or sulfur dioxide (SO2) and / or ammonia (NH3), and at least about 0.1 mol% of contaminating refinery hydrocarbons. The aqueous compositions are suitable for use in fertilizer, mining and industrial applications.

The invention discloses a hydrogen sulphide-containing gas treatment device. The device comprises a cooler, a mixer and a crystallization tower; a hydrogen sulphide-containing gas feeding pipeline is connected with an inlet of the cooler; an outlet of the cooler is connected with an inlet of the mixer; the inlet of the mixer is also connected with the hydrogen sulphide-containing gas feeding pipeline; an outlet of the mixer is connected with an inlet of the crystallization tower. The invention also discloses a hydrogen sulphide-containing gas treatment method. According to the hydrogen sulphide-containing gas treatment method and the hydrogen sulphide-containing gas treatment device, the hydrogen sulphide is separated from a hydrogen sulphide-containing gas and simultaneously an ammonium hydrogen sulphide product is obtained by utilizing the characteristic that ammonia gas and hydrogen sulphide perform gas phase reaction to generate ammonium hydrogen sulphide; the method is simple in process and low in energy consumption, is particularly suitable for separating acid gas of a refinery plant; the used crystallization tower has the advantages that crystal substances fall easily, the surface on which the crystal substances can be attached is large and the like.