2611 results about "Water chlorination" patented technology

Methods for disinfecting surfaces and for sanitizing bodies of water using a single-feed, bromine-based biocide are described. These methods use concentrated liquid biocide compositions comprising biocidally active bromine as the biocide. Also described is a process of producing the concentrated liquid biocide composition: mixed together are (a) bromine chloride and (b) an aqueous solution of alkali metal salt of sulfamic acid having a pH of at least about 7, in amounts such that (i) the active bromine content of the composition is at least about 100,000 ppm (wt / wt), and (ii) the atom ratio of nitrogen to active bromine in the composition is greater than 0.93. Use of bromine chloride as the source of the active bromine in the process is advantageous because in the resulting aqueous compositions, all of the bromine of the bromine chloride is made available as active bromine in solution. In other words, the chlorine of the bromine chloride is converted in the process to dissolved alkali metal chloride salt, thereby liberating all of the bromine as the active bromine content of the biocidal composition.

The present invention provides one-step processes for the production of chlorinated and / or fluorinated propenes. The processes provide good product yield with low, e.g., less than about 20%, or even less than 10%, concentrations of residues / by-products. Advantageously, the processes may be conducted at low temperatures than 500° C. so that energy savings are provided, and / or at higher pressures so that high throughputs may also be realized. The use of catalysts or initiators may provide additional enhancements to conversion rates and selectivity, as may adjustments to the molar ratio of the reactants.

The present invention provides continuous, gas phase, free radical processes for the production of chlorinated and / or fluorinated propenes or higher alkenes from the reaction of chlorinated and / or fluorinated alkanes and chlorinated and / or fluorinated alkenes, wherein wherein at least a portion of any intermediate boiler by-products generated by the process are removed from the process.

Provided is a method for manufacturing polysilicon and silicon tetrachloride. The polysilicon manufacturing process used in said method is energy-efficient and can use an inexpensive raw material, the supply of which is stable. The chlorination reaction in said process proceeds smoothly and post-chlorination impurities are minimized. The provided method comprises: a chlorination step which generates silicon tetrachloride by chlorinating granules comprising silicon dioxide and a carbon-containing substance; a reduction step which generates polysilicon by using a reducing metal to reduce the silicon tetrachloride; and an electrolysis step which generates chlorine gas and a reducing metal by performing molten-salt electrolysis on a reducing metal chloride generated as a by-product from the reduction step. In the chlorination step, chlorine gas is supplied to the silicon dioxide and the carbon-containing substance in the presence of oxygen gas in order to react said substances. The reducing metal generated in the electrolysis step is reused as the reductant for the silicon tetrachloride in the reduction step, and the chlorine gas generated in the electrolysis step is reused in the chlorination step.

The present invention provides one-step processes for the production of chlorinated and / or fluorinated propenes. The processes provide good product yield with low, e.g., less than about 20%, or even less than 10%, concentrations of residues / by-products. Advantageously, the processes may be conducted at low temperatures relative to conventional processes, so that energy savings are provided, and / or at higher pressures so that high throughputs may also be realized. The use of catalysts may provide enhancements to conversion rates and selectivity over those seen in conventional processes, as may adjustments to the molar ratio of the reactants.

Improved, non-chlorinated systems and methods for removing soils from hard surfaces are provided wherein such surfaces are initially contacted with a first aqueous use dispersion including a protease enzyme, followed by contact the surface with a second aqueous acidic use dispersion. The enzyme dispersion preferably includes a polyol such as propylene glycol and in use is heated to a temperature up to about 120° C. The acid dispersion may include a surfactant and is also used in a heated condition. The two-component systems of the invention can be used for CIP treatment of dairy or other equipment in lieu chlorinated cleaning agents.

The invention belongs to the technical field of composite membrane materials, and particularly relates to a preparation method for a layered double hydroxides composite material and an application of the layered double hydroxides composite material in heavy metal wastewater. The preparation method comprises the steps of: by adopting a coprecipitation method, firstly preparing a nitrate or chlorate aqueous solution A of divalent metal cations M<2+> and a nitrate or chlorate aqueous solution of trivalent metal cations M<3+>, and adding an aqueous solution C wherein organic salt of a heavy metal ion chelating agent is fully dispersed; obtaining layered double hydroxides of the heavy metal ion chelating agent through aging, vacuum drying, crushing and sieving; and mixing the layered double hydroxides with PVA to prepare a membrane and then preparing an LDHs / PVA composite membrane. As a composite membrane adsorbing material is soaked into heavy metal wastewater containing Cu<2+>, Cd<2+> or Pb<2+>, the adsorption rate can reach 92%. The method provided by the invention is mild in preparation condition and low in cost and has a good application prospect.

The present invention provides adiabatic plug flow reactors suitable for the production of chlorinated and / or fluorinated propene and higher alkenes from the reaction of chlorinated and / or fluorinated alkanes and chlorinated and / or fluorinated alkenes. The reactors comprise one or more designs that minimize the production of by-products at a desired conversion.

An algaecide formulated in a concentrated, solid composition form for subsequent dissolution in water is disclosed. The algaecide is designed to remove algae from a variety of interior and exterior surfaces. The preferred algaecide compositions chlorinated isocyanurates, such as sodium dichloro-s-triazinetrione, alkali hydroxides selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, and lithium hydroxide; metal sulfates selected from the group consisting of copper sulfate, zinc sulfate, and aluminum sulfate; and a buffer.

The invention discloses a method and a device for simultaneous reduction and oxidation of nitrogen oxides from airflow. According to a treating process, the treated airflow is guided into a gas-solid reaction tower, solid ferrous chloride, ferric chloride, manganese chloride or magnesium chloride metal chloride particles are guided into the gas-solid reaction tower simultaneously, and the metal chloride is decomposed at the high temperature and reacts with nitric oxide in the airflow, so that part of nitric oxide contained in the airflow is reduced to nitrogen, the rest nitric oxide is oxidized into nitrogen dioxide, generated nitrogen dioxide reacts with an alkaline absorbent easily to be removed, and the purpose of gas purification is achieved. The invention further discloses the special device. The method and the device have the characteristics of low investment cost as well as operation and application cost, simplicity in operation, high treatment efficiency and high treatment capacity.

The invention relates to a method for preparing blocky ferric trichloride. Blocky ferric trichloride can be produced both under constant-temperature crystal growing condition at 5-10 DEG C and at high-temperature environment temperature by adjusting the parameters of crystal cooling and crystal growing. In addition, solid ferric trichloride is used as a raw material, and impurities in the traditional pickling waste liquid are prevented from being mixed into a product; and chlorine gas is used as an oxidizing agent and does not contain any impurity. Finally, the blocky ferric trichloride can be directly obtained through crystal growing, the area of blocky ferric trichloride in direct contact with the air is small, the problem that ferric trichloride absorbs moisture easily can be effectively solved, the quality guarantee period of the product is prolonged, and the blocky ferric trichloride is easy to store and transport.

The invention provides a method for comprehensively recycling valuable metals from lead anode slime by oxygen pressure treatment, which is characterized in that oxygen pressure alkali dip, potential-controlled chlorination leaching, fractional hydrolysis and other techniques are utilized to efficiently separate and recycle As, Sb, Bi, Cu and other valuable metals from lead anode slime, and gold, silver and lead enriched residues are transformed and subjected to fire smelting-electrolytic refining to recycle gold, silver and lead. By combining wet-process pretreatment for separating base metals with the pyrogenic process, the technique provided by the invention can efficiently remove arsenium contained in the fresh complex lead anode slime without losing lead, fundamentally solves the problem of lead and arsenium hazards and reduces the loss of valuable metals in the process; and the invention has the characteristics of strong adaptability to raw materials, high efficiency, high cleanness, low comprehensive energy consumption, high gold and silver yields, high enrichment ratio of valuable metals, high industrialization degree and the like, is simple to operate, and simultaneously implements closed-loop regenerative cycle and no pollutant waste discharge in the process. The gold yield is higher than 99.5%, the silver recycling rate is higher than 99%, the lead yield is higher than 98%, and the yield of other valuable metals is higher than 98%. The invention can independently form a system, and can also be used for improving and perfecting the pyrogenic process, thereby having high popularization value.