Showing papers on "Sodium chlorate published in 2017"
TL;DR: The role and importance of chromium(VI) in the chlorate manufacturing process is discussed in this article, where previous achievements in its replacement are summarized and critically evaluated to expose the current state of the field, and highlight the most promising avenues to be followed.
37 citations
TL;DR: Delamination and pre-expansion phenomena were observed only for nitric acid, sodium chlorate, and hydrogen peroxide, while the presence of strong oxidizers led to stable graphite intercalation compounds.
Abstract: Different chemical formulations for the synthesis of highly intercalated graphite bisulfate have been tested. In particular, nitric acid, potassium nitrate, potassium dichromate, potassium permanganate, sodium periodate, sodium chlorate, and hydrogen peroxide have been used in this synthesis scheme as the auxiliary reagent (oxidizing agent). In order to evaluate the presence of delamination, and pre-expansion phenomena, and the achieved intercalation degree in the prepared samples, the obtained graphite intercalation compounds have been characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD), infrared spectroscopy (FT-IR), micro-Raman spectroscopy (μ-RS), and thermal analysis (TGA). Delamination and pre-expansion phenomena were observed only for nitric acid, sodium chlorate, and hydrogen peroxide, while the presence of strong oxidizers (KMnO4, K2Cr2O7) led to stable graphite intercalation compounds. The largest content of intercalated bisulfate is achieved in the intercalated compounds obtained from NaIO4 and NaClO3.
25 citations
TL;DR: In this paper, the rate of chlorate formation can be described as an uncatalyzed third order reaction with respect to hypochlorite species and a parallel chromate catalyzed reaction of apparent reaction order 2.2.
Abstract: Electrolyte used in the manufacturing process of sodium chlorate contains chromate primarily to inhibit cathodic loss reactions. Chromate also accelerates the chlorate formation reaction which reduces the concentration of hypochlorite species in the chlorate cell leading to enhanced anodic current yield, reduced risk of oxygen explosions and reduced cost for the purification of the cell gas. Laboratory scale trials show that the rate of chlorate formation can be described as an ‘uncatalyzed’ third order reaction with respect to hypochlorite species and a parallel chromate catalyzed reaction of apparent reaction order 2.2. Validation is presented based on data from electrolysis trials in pilot plant and bench scale at technically relevant conditions. If the dichromate concentration is increased from 0 to 5 g/L, more than 50% of the chlorate may be formed via the chromate catalyzed path and the apparent reaction order changes from 3 to about 2.4. The kinetic effect of the chromate species also lowers the optimum reaction pH below that of the uncatalyzed reaction. Furthermore, anionic hypochlorite does not seem to be necessary to generate chlorate via the chromate catalyzed path. Other hypochlorite consuming reactions such as anodic and homogeneous oxygen formation as well as cathodic reduction and desorption of chlorine species in the cell gas only have a marginal effect on the hypochlorite concentration in the chlorate cell.
20 citations
TL;DR: In this paper, it has been found that mixtures between sodium chlorate and HCl (NaClO3 + HCl ⇆ HClO 3 + NaCl + NaO3) in 20 mL are effective media for the dissolution of pure gold-wire (99.95 %, ca. 50fold increase) for 1.0 mol dm-3 HCl and HBr, respectively, where the pseudo-first-order dissolution rate constants (k/s-1) have been evaluated by the changes in the mass of goldwire.
9 citations
TL;DR: In this article, a pilot cell unit for executing the sodium chlorate process was constructed to study the current efficiency of the anode and cathode separately, and the results showed that the cathodic current efficiency increases with increasing dichromate concentrations in the electrolyte until approximately 5g−3 is reached.
Abstract: Current efficiency in the sodium chlorate process is a key issue in the evaluation of the power consumption. A pilot cell unit for executing the sodium chlorate process was constructed to study the current efficiency of the anode and cathode separately. The effects of sodium dichromate and sodium sulphate concentrations and the electrolyte temperature on the anode and cathode current efficiencies were studied. Corrosion products formed on the mild steel cathodes after their removal from the cell were characterised using X-ray diffraction and infrared spectroscopy. The results show that the cathodic current efficiency increases with increasing dichromate concentrations in the electrolyte until approximately 5 g dm−3 is reached. At this optimum concentration of dichromate, the presence of sulphate ions decreases the cathodic current efficiency. For moderate increases in temperature, the cathodic current efficiency increases, but oxygen evolution is promoted, and the power consumption also increases. Surface characterisation of the electrodes after their exposure to air shows two primary types of behaviour, depending on the process parameters. At low dichromate concentrations, amorphous corrosion layers are formed, while at higher concentrations, reduced forms of iron hydroxides, i.e., “green rust”, are identified. Although the electrodes were positioned at the open circuit potential for 40 min before their removal from the cell, chromium remains on the cathode surface. This result might explain the corrosion-inhibiting effect of the addition of chromate to the electrolyte. The results from this study can be used to optimise operating procedures in real plants, decrease the energy consumption and minimise the environmental impact of these processes.
6 citations
Patent•
26 Apr 2017
TL;DR: In this article, a method for preparing sodium chlorate from industrial salt is described, which consists of mixing the industrial salt and water to prepare industrial brine, filtering the industrial brines to remove solid impurities, and putting the obtained industrial briny into an electrolytic cell for electrolysis to obtain the sodium chloride solution.
Abstract: The invention discloses a method for preparing sodium chlorate from industrial salt. A sodium chlorate solution is obtained mainly via ionization, and sulfate ions in the sodium chlorate solution are removed to finally obtain a refined sodium chlorate product. The method comprises the following steps: mixing the industrial salt and water to prepare industrial brine; filtering the industrial brine to remove solid impurities; putting the obtained industrial brine into an electrolytic cell for electrolysis to obtain the sodium chlorate solution; and carrying out vacuum low-temperature continuous evaporative crystallization on obtained sodium chlorate electrolyte to obtain a sodium chlorate crystallized solution, carrying out centrifugal separation, adding a solution mixture of calcium chloride and barium chloride into sodium chlorate mother liquor for reaction, and adding a flocculating agent into the sodium chlorate mother liquor for clarification. Compared with the prior art, the method has the beneficial effects that high yield per unit time is realized in a production electrolysis process of sodium chlorate by controlling the ratio of the calcium chloride to the barium chloride through ceaseless freezing, evaporation and electrolytic cyclic treatment processes, and the power consumption per yield is reduced.
4 citations
01 Jan 2017
TL;DR: In this article, a new membrane electrolysis process for bismuth recovery from Bismuthinite concentrate was introduced, and the resulting leach solution was subjected to membrane electrolyisation.
Abstract: A new membrane electrolysis process for bismuth recovery from bismuthinite concentrate was introduced. Under the conditions of temperature 70 °C, acidity 3 mol/L, solid liquid ratio 1:4 and 1.1 times stoichiometry sodium chlorate dosage for 1.5 h oxidation leaching, more than 98.5% bismuth can be leached from bismuthinite concentrate. The resultant leach solution was subjected to membrane electrolysis. Under the conditions of NaCl concentration 300 g/L and pH 7 in anolyte, bismuth ions concentration 80 g/L and HCl concentration 3 mol/L in catholyte, heteropole distance 6 cm, temperature 40 °C and current density 200 A/m2, a flat deposited bismuth plate can be obtained after 24 h electrolysis, and the bismuth purity was more than 99%. The current efficiency of cathode was 97.88%. Chemical component analysis results showed that the average convert efficiency of the sodium chlorate was 52.77% and the average oxidizing efficiency of chloride ion was 69.78%, and the resultant anolyte generated in anode compartment could be fully reused as oxidant for leaching bismuthinite concentrate again.
3 citations
24 Apr 2017
TL;DR: In this paper, two different FeOOH species were synthesized in pure form to elucidate if their electrocatalytic properties were the reason for their different performance, and the authors concluded that it is the semiconductor properties of the materials that explain that the hypochlorite reduction at Cr(III) is inhibited while the reduction readily can proceed at iron (oxy)hydroxides.
Abstract: Sodium chlorate is an important industrial chemical produced through an electrochemical manufacturing process. The global production rate is 3.6 million tons annually and consumes approximately 20 TWh of electrical power. The majority of the produced sodium chlorate is used as raw material to make chlorine dioxide for the bleaching of kraft pulp. This thesis aims to provide a deeper understanding on the mild steel cathode and the role sodium dichromate has in the electrolyte in the chlorate process. Such understanding would allow reduction of the energy consumption, in particular, as well as the overall manufacturing footprint. Two separate sodium chlorate plants have shown different performances in terms of current efficiency and corrosion of the mild steel cathodes. Surface characterisations and current efficiency measurements were performed on the two cathodes in order to evaluate the difference in performance between the samples. Two types of FeOOH were found on the individual cathodes: goethite (α-FeOOH) on the normally performing cathode and lepidocrocite (γ-FeOOH) on the poorly performing cathode. The two different FeOOH species were synthesised in pure form to elucidate if their electrocatalytic properties were the reason for their different performance. Both goethite and lepidocrocite showed lower activity for the reduction of water compared to polished mild steel but almost equally good towards hypochlorite reduction. The difference in performance of the pure phases can therefore not explain their differences in behaviour in large scale performance. However, in situ Raman spectroscopy revealed that the active species on the surface of the mild steel cathode was Fe(OH)2 and the kinetics for the reduction of the surface from Fe(III) to Fe(II) was also found to be different between the two types of corrosion products. These findings are the reason for the observed differences in current efficiency. Reduction of hypochlorite is the most important loss reaction in the chlorate process and Cr(VI) is added to the electrolyte to inhibit this reaction. A Cr(III) film formed at the cathode provide selectivity towards hydrogen evolution. The mechanism of hypochlorite reduction at Fe(III) and Cr(III) was studied by Density Functional Theory (DFT) calculations in order to understand the blocking effect of the Cr(III) film. The electro catalytic properties was shown to be very similar for Fe(III) and Cr(III) and cannot explain the blocking effect of Cr(III). However, the experimental results clearly demonstrated that the Cr(III) film was completely blocking of the hypochlorite reduction. It was concluded that it is the semiconductor properties of the materials that explain that the hypochlorite reduction at Cr(III) is inhibited while the reduction readily can proceed at iron (oxy)hydroxides. A pilot plant was used to investigate the long term effects from continuous operation. Three process parameters were tested in the pilot plant to investigate the formation of different corrosion products on the cathode surface and their effect on the energy efficiency. These three were concentration of dichromate, sulphate and the temperature of the electrolyte. The pilot plant studies revealed possibilities to optimise the current efficiencies and corrosion of the cathodes with respect to the operating and shutdown conditions. Finally recommendations are issued, as to how a sodium chlorate producer should relate to the results in order to minimize the losses in current efficiencies and cathodic corrosion.
3 citations
Patent•
31 May 2017
TL;DR: In this paper, a production technology of anti-caking sodium chlorate is described, which consists of crystal separation on the sodium chloride electrolyte to obtain sodium chlorates, and then preparing a saturated sodium chloride solution from the obtained in the step (1) for standby application, taking and placing 500ml of the saturated salt solution in a beaker, adding 2-5g of a surfactant, performing stirring to enable the surfactants to dissolve in the saturated saliency, and performing uniform stirring, and standing for ten minutes to obtain a feed liquid.
Abstract: The invention discloses a production technology of anti-caking sodium chlorate. The production technology comprises the following steps of: (1) performing crystal separation on sodium chlorate electrolyte to obtain sodium chlorate; (2) preparing a saturated sodium chlorate solution from the sodium chlorate obtained in the step (1) for standby application, taking and placing 500ml of the saturated sodium chlorate solution in a beaker, adding 2-5g of a surfactant, performing stirring to enable the surfactant to dissolve in the saturated sodium chlorate solution, then adding 500g of sodium chlorate crystals, performing uniform stirring, and performing standing for ten minutes to obtain a feed liquid; (3) performing vacuum filtration on the feed liquid obtained in the step (2), and placing the obtained sodium chlorate crystals in which the surfactant is adsorbed in a constant-temperature drying oven of 12-15 DEG C for drying; and (4) loading the dried sodium chlorate in a plastic sample bag, and performing sealing. The production technology disclosed by the invention is good in anti-caking effect, small in quantity of reagents, and low in cost.
2 citations
Patent•
11 Aug 2017
TL;DR: In this article, a preparation method of a sodium chlorate generator electrode is described, which consists of matrix treatment, inner layer active coating liquid, inner-layer metal oxide, outer-layer active liquid, outer layer active layer liquid, and electrode preparation.
Abstract: The invention discloses a preparation method of a sodium chlorate generator electrode. The preparation method comprises the following steps of (1) matrix treatment, (2) preparation of inner-layer active coating liquid, (3) preparation of inner-layer metal oxide, (4) preparation of outer-layer active coating liquid, and (5) preparation of the electrode. According to the novel preparation method of the sodium hypochlorite generator electrode, the prepared electrode has the advantages of being low in chlorine evolution potential, high in oxygen evolution potential, energy-saving, environmentally friendly, long in service life and high in electrolytic efficiency.
Patent•
15 Feb 2017
TL;DR: In this article, the utility model discloses a sodium chlorate reactor for synthetic method chlorine dioxide preparing system, including reactor noumenon (3), C room barrel (4), center tube (13), and baffle (18) with reactor nousmenon's (3) inside space separation one -tenth A room (20) and B room (21), the upper portion at reactor noudmenon(3) inner wall is fixed in baffle(18), lower extreme is close reactornousman(3), bottom, center tube(13
Abstract: The utility model discloses a sodium chlorate reactor for synthetic method chlorine dioxide prepares system, including reactor noumenon (3), C room barrel (4) and center tube (13), C room barrel (4) form independent space C room (22) inside being located reactor noumenon, and baffle (18) with reactor noumenon's (3) inside space separation one -tenth A room (20) and B room (21), the upper portion at reactor noumenon (3) inner wall is fixed in baffle (18), baffle (18) lower extreme is close reactor noumenon (3) reactor bottom, center tube (13) are located the top intermediate position of reactor noumenon (3), and communicate with each other with reactor noumenon (3), structural design through the reactor, sufficient reaction time is provided for the reaction that begins at the electrolysis trough, collect the next weak sodium chlorate solution from chlorine dioxide synthesis unit, it obtains strong sodium chlorate electrolyte to mix weak sodium chlorate solution and cross strong sodium chlorate electrolyte, raw materials as production chlorine dioxide.
Patent•
15 Feb 2017
TL;DR: In this paper, a synthesis method of polymeric ferric sulfate chloride is presented. But the synthesis method comprises the following steps: at first, adjusting the contents of following components in iron-containing waste sulfuric acid: Fe >= 4.5 wt%, and H2SO4 >= 6.0 wt.
Abstract: The invention discloses a synthesis method of polymeric ferric sulfate chloride. The synthesis method comprises the following steps: at first, adjusting the contents of following components in iron-containing waste sulfuric acid: Fe >= 4.5 wt%, and H2SO4 >=6.0 wt%; adjusting the contents of following components in iron-containing waste hydrochloric acid: Fe >= 11 wt%, and HCl >=6.0 wt%; adding iron-containing waste sulfuric acid, iron-containing waste hydrochloric acid, and ferrous sulfate heptahydrate according to a mass ratio of 1:025-1:1.39-1.49, pumping the mixture into a circulation oxidation reactor; adding a sodium chlorate solution and a sodium nitrite solution in sequence, and introducing oxygen into the reactor, wherein when the total iron content reaches 10.0 to 11.5 wt%, Fe content is not more than 0.1 wt%, and the basicity is 4-16%, the reactions finish. The synthesis method has the advantages that the pollution of waste acids to the environment is reduced, the product stability is good, the flocculating effect is good, the production cost is low, the production period is prominently reduced, the energy consumption is reduced, and the production cost is further reduced.
Patent•
31 May 2017
TL;DR: In this paper, a passivation solution which is prepared by dissolving various raw materials in deionized water is presented, which includes chromium sulfate hexahydrate, 2-4 g/L of cobalt sulfate heptahydrates, 4-8 g/l of sodium chlorate, ammonium fluoride, 1-2 g /L of sulfuric acid, 2 -3 g /l of citric acid and the balance water.
Abstract: The invention provides a passivation solution which is prepared by dissolving various raw materials in deionized water. The materials comprise 6-9 g/L of chromium sulfate hexahydrate, 2-4 g/L of cobalt sulfate heptahydrate, 4-8 g/L of sodium chlorate, 2-3 g/L of ammonium fluoride, 1-2 g/L of sulfuric acid, 2-3 g/L of citric acid and the balance water. According to an obtained passivation film, the corrosion resisting property is good, a salt spray test can be kept for 120 h or longer, the workpiece surface has no white rust or white spot, the porosity is low, and no sealing agent is needed for treatment.
Patent•
07 Jun 2017
TL;DR: In this paper, a chloride donor is introduced into a feed of sulfuric acid or a reducing agent, both of which are injected into the recirculation lines, or other areas, of a chlorine dioxide producing facility.
Abstract: A method for boosting the efficiency of chlorine dioxide production in a chemical facility. A chloride donor is introduced into a feed of sulfuric acid or a reducing agent, both of which are injected into the recirculation lines, or other areas, of a chlorine dioxide producing facility. The chloride donor provides the intermediate chemical species necessary for the efficient generation of chlorine dioxide at high acidities and/or the high local acidity in the wake zone of the acid injection location, thereby enabling greater efficiency in the reduction of chlorine dioxide from sodium chlorate.
Patent•
24 Nov 2017
TL;DR: In this paper, a comprehensive treatment method for 1, 4-diamino-2-anthraquinonesulfonic acid wastewater was proposed, which includes the steps of: adding industrial 1.4-Diamino, 2.5-anthrquinones sulfonic acid (A2A) wastewater into a container, calculating the content of sodium 3, 4dichlorobenzenesulfonate therein, according to a sodium 3.4:0.34-0.40, adding all the hydrochloric acid into the container, and
Abstract: The invention discloses a comprehensive treatment method for 1, 4-diamino-2-anthraquinonesulfonic acid wastewater. The method includes the steps of: adding industrial 1, 4-diamino-2-anthraquinonesulfonic acid wastewater into a container, calculating the content of sodium 3, 4-dichlorobenzenesulfonate therein, according to a sodium 3, 4-dichlorobenzenesulfonate, hydrochloric acid and sodium chlorate mole ratio of 1:0.34-0.4:0.34-0.40, adding all the hydrochloric acid into the container, and performing stirring till reflux; adding a sodium chlorate solution dropwise, maintaining a dripping speed of 20-30 drops per minute, at the same time maintaining a reflux oil separation state; at the end of dripping, maintaining the reflux oil separation state for 30-90min till no oil slick in condensate liquid, and separating trichlorobenzene. The method provided by the invention adopts chemical reaction, converts sodium 3, 4-dichlorobenzenesulfonate in wastewater into 1, 3, 4-trichlorobenzene, and separates 1, 3, 4-trichlorobenzene from wastewater by distillation, greatly reduces the COD of wastewater and reaches the emission standard. The small amount of recovered trichlorobenzene can be used or sold as a by-product, also the strong oxidizing properties of sodium chlorate can be utilized for complete oxidation decomposition of other unknown organic matters in wastewater, and the chroma of wastewater is reduced.
Patent•
21 Sep 2017
TL;DR: In this paper, the problem of providing a sodium hypochlorite pentahydrate crystal in which the content of sodium chlorate whose harmfulness to the health has been considered as a problem is reduced is solved.
Abstract: PROBLEM TO BE SOLVED: To provide a sodium hypochlorite pentahydrate crystal in which the content of sodium chlorate whose harmfulness to the health has been considered as a problem is reduced.SOLUTION: Provided is a sodium hypochlorite pentahydrate crystal in which the concentration of sodium hydroxide included in the surface or at the inside of the sodium hypochlorite pentahydrate crystal is 0.01 to 0.8 wt.%. Also provided is a method for producing a sodium hypochlorite pentahydrate crystal where a sodium hypochlorite aqueous solution in which effective chlorine concentration is regulated to 20% or higher and sodium hydroxide concentration is regulated to 2.0 to 5.0% is subjected to crystallization while being cooled.SELECTED DRAWING: Figure 1
Patent•
29 Sep 2017
TL;DR: In this paper, a technology for recycling and utilizing wastewater produced in oxosynthesis of quinolinic acid by sodium chlorate is presented, which is simple, green and environment-friendly effects are realized, the total yield rate of reaction reaches 82% or above, and the content reaches 99 % or above.
Abstract: The invention discloses a technology for recycling and utilizing wastewater produced in oxosynthesis of quinolinic acid by sodium chlorate. The technology comprises the following steps of using the wastewater produced in the oxosynthesis of the quinolinic acid by the sodium chlorate as an initiator, using quinoline, sodium chlorate and copper sulfate as raw materials, and respectively performing oxidizing reaction, alkaline reaction and acidifying reaction, so as to obtain the quinolinic acid. Compared with the prior art, the technology has the advantages that the wastewater produced in the oxosynthesis of the quinolinic acid by the sodium chlorate can be recycled and utilized; the technology is simple, the green and environment-friendly effects are realized, the total yield rate of reaction reaches 82% or above, and the content reaches 99% or above.
30 May 2017
TL;DR: In this paper, the effect of chlorate ions on the anodic dissolution of aluminium and its alloys with magnesium under conditions of high current densities and intensive electrolyte mixing is investigated using the method of anodic polarisation curve removal on a rotating disk electrode.
Abstract: The effect of chlorate ions on the anodic dissolution of aluminium and its alloys with magnesium under conditions of high current densities and intensive electrolyte mixing is investigated using the method of anodic polarisation curve removal on a rotating disk electrode. It is shown that at relatively low anodic potential values the process is limited by the capacity of the electrochemical reaction, but with a further potential shift and a venting of the reaction products from the surface of the anode. The effective smoothing of the surface microrelief of aluminium alloys in solutions of chlorates is due to the periodic formation and destruction on the treated surface of a specific oxide film and inhibition due to the electrochemical heterogeneity of the structural components of the alloys.
Patent•
04 Jan 2017
TL;DR: In this article, a method for extracting tellurium from a high selenium-and-lead-impurity content is proposed. But the method is not suitable for high-purity industrial applications.
Abstract: The invention discloses a method for extracting tellurium from tellurium dioxide with the high selenium-and-lead-impurity content. The method includes the following steps that (1) the tellurium dioxide with the high selenium-and-lead-impurity content is dissolved into a sodium hydroxide solution, filtering is carried out, and alkali leached filtrate is obtained; (2) sodium sulfide is added into the alkali leached filtrate for lead removing, standing is carried out, then filtering is carried out, and purified liquid is obtained; (3) sodium chlorate is added into the purified liquid, and white sodium tetrahydrotellurate sedimentation is obtained; (4) the sodium tetrahydrotellurate sedimentation and a sodium hydroxide solution are mixed to obtain sodium tetrahydrotellurate; (5) the sodium tetrahydrotellurate is put into high-purity hydrochloric acid, completely dissolved and heated, then sodium hydrogen sulfite is added for reduction, and powdery metal tellurium is obtained. According to the method, the alkali dissolution, purification impurity removing, oxidation, hydrochloric acid dissolution and reduction washing technology is adopted, tellurium is extracted from tellurium dioxide with the high selenium-and-lead-impurity content, separation of tellurium and impurities such as selenium and lead is effectively achieved, No.3 tellurium meeting the national standard YS/T 222-2010 can be generated, and the method has the advantages of being short in technology process, low in production cost, high in recovery rate and stable in product quality.
Patent•
30 Jun 2017
TL;DR: In this article, a dissolving method of pure coarse cobalt carbonate is described, which is suitable for preparation of hydroxy cobalto-cobaltic oxide.
Abstract: The invention discloses a dissolving method of pure coarse cobalt carbonate. The dissolving method is characterized in that: in step 1, a pH (Potential of Hydrogen) value is regulated to be 3.0 to 3.5; only 90 percent of cobalt and copper are completely dissolved, Fe is basically not generated, and auxiliary materials including sodium chlorate and sodium carbonate do not need to be added for removing impurities; in step 2, the volume of cobalt slag is small; meanwhile, the content of valuable metal including cobalt and copper is only 10 percent, and the pH value is regulated for 2 percent to 2.5 percent to completely dissolve out the cobalt slag; less sulfuric acid and pyrosulfurous acid are added, so that the dissolving of the impurities is reduced, and the corresponding consumption amount of the sodium chlorate is less; calcium oxide powder is used for replacing the sodium carbonate to neutralize and remove the impurities; meanwhile, calcium sulfate sediment is generated by surplus calcium under high temperature; the pure coarse cobalt carbonate has the advantages of good filtering performance, high transparency of a sodium carbonate solution and stable quality, and is suitable for preparation of hydroxy cobalto-cobaltic oxide.
Patent•
08 May 2017TL;DR: In this article, a system for integral chlorine dioxide production with relatively independent sodium chlorate electrolytic production and chlorine dioxide synthesis is described, where the system may feed electrolyte solution into a solid-liquid filter, filtering out the crystal and eliminating sodium chloride and sodium dichromate.
Abstract: A system for the integral chlorine dioxide production with relatively independent sodium chlorate electrolytic production and chlorine dioxide production is provided. The system may feed electrolyte solution into a solid-liquid filter, filtering out the crystal and eliminating sodium chloride and sodium dichromate. The sodium chlorate crystal may be fed into a chlorine dioxide generator after dissolving, while sodium chloride and sodium dichromate solution separately return to electrolyzer for electrolysis process. Sodium chloride may be constantly formed as a by-product in the chlorine dioxide production unit, and solution containing the sodium chloride is withdrawn from the generator and, after filtration, washing and dissolution, recycled back to sodium chlorate production unit. This way, there is no need of sodium chloride make-up.
Patent•
23 Nov 2017
TL;DR: An antirust agent for a black metal object, comprising 10-30 parts of sodium chlorate, 300-500 parts of thermosetting phenolic resin, 100-300 parts of naphthenic acid, 80-150 parts of Sodium oxide, 150-300 part of aluminum silver powder, 50-100 parts of talcum powder, and 20-80 parts of boric acid is described in this paper.
Abstract: An antirust agent for a black metal object, comprising 10-30 parts of sodium chlorate, 300-500 parts of thermosetting phenolic resin, 100-300 parts of naphthenic acid, 80-150 parts of sodium oxide, 150-300 parts of aluminum silver powder, 50-300 parts of talcum powder, and 20-80 parts of boric acid.
TL;DR: Sodium chlorate residues were stable (P > 0.05) in frozen tomato and cantaloupe homogenates during storage for 119 days at -24 °C.
Abstract: The objective of this study was to determine the stability of sodium chlorate in frozen (−24 °C) tomato or cantaloupe homogenates for up to 17 weeks (119 days). Chlorate stability was assessed by ultraperformance liquid chromatography–mass spectrometry (UPLC-MS/MS) at two fortification levels (80 or 600 ng/g for tomato and 200 or 3000 ng/g for cantaloupe, n = 3 each) for each fruit after storage for 0, 1, 7, 14, 28, 56, or 119 d. Within matrix type, chlorate recovery was determined by fortifying duplicate blank homogenate samples on the day of analysis with the same concentrations used for the stability samples. Chlorate limits of quantitation for cantaloupe and tomato matrices were 30 and 60 ng/g, respectively. Sodium chlorate residues were stable (P > 0.05) in frozen tomato and cantaloupe homogenates during storage for 119 days at −24 °C.
Patent•
01 Sep 2017
TL;DR: In this paper, a preparation and decomposition control method of high-purity chlorine dioxide is proposed. But the method is not suitable for high purity and no pollution, safety, reliability and the like.
Abstract: The invention discloses a preparation and decomposition control method of high-purity chlorine dioxide The preparation and decomposition control method comprises the following operation steps: firstly, assembling a chlorine dioxide generating device; secondly, putting one or two solutions of analytical pure methanol and hydrogen peroxide into a beaker; thirdly, adding a sodium chlorate solution into the solution obtained in the second step, uniformly mixing and then adding a mixed solution into a separating funnel of a reactor of the generating device; fourthly, adding a sulfuric acid solution into another separating funnel; fifthly, pouring a sodium perborate or sodium percarbonate solution into three absorption bottles, and filling another absorption bottle with a sodium hydroxide solution By using a mixed solution prepared from sodium chlorate, methanol and hydrogen peroxide to react with the sulfuric acid solution under the condition of water bath heating, the high-purity chlorine dioxide solution is obtained through the chlorine dioxide generating device; the decomposition of chlorine dioxide can be inhibited while ClO2 is absorbed by the absorption device The preparation method disclosed by the invention has the characteristics of low preparation cost of the chlorine dioxide, high purity, no pollution, safety, reliability and the like; the utilization rate of raw materials and the purity of products can be improved
TL;DR: In this paper, the reaction rate is first order in PCC and fractional order in [H + ] and has aldehyde as a product, the reaction increases with increase in the percentage of acetic acid medium and added Mn (II) decreases the rate of reaction.
Abstract: Oxidation of cis α-phenyl cinnamic acids by pyridinium chlorochromate (PCC) was studied in acetic acid–water mixture containing perchloric acid. The reaction rate is first order in [PCC] and fractional order in [H + ] and has aldehyde as a product. The rate of reaction increases with increase in the percentage of acetic acid medium. The reactions exhibit kinetic isotope effect. The activation parameters have been evaluated. The added Mn (II) decreases the rate of reaction. The added sodium chlorate has no effect on the reaction rate and indicates the absence of ion-ion (or) ion- dipole interaction in the slow step. The deviation of Hammett plot is noted and a “V” shaped curve is obtained.
Patent•
11 Jan 2017
TL;DR: In this article, the indium recovery method comprises the following steps: (S1) smashing and screening: an indium phosphide waste is smashed for passing through a sieve of 100 meshes; (S2) leaching: a raw material after passing through the sieve, water are added according to a liquid-solid ratio of (4-7): 1 for uniform stirring; then, a certain quantity of sodium chlorate solid is added inside for heating to 60-80 DEG C; and (S3) replacement: the leaching liquid is diluted and
Abstract: The invention relates to an indium recovery method The indium recovery method comprises the following steps: (S1) smashing and screening: an indium phosphide waste is smashed for passing through a sieve of 100 meshes; (S2) leaching: a raw material after passing through the sieve of 100 meshes and water are added according to a liquid-solid ratio of (4-7): 1 for uniform stirring; then, a certain quantity of sodium chlorate solid is added inside for heating to 60-80 DEG C; and a certain quantity of concentrated hydrochloric acid with a solute mass fraction of 29-36% is dripped inside to always keep pH within -03-0, so that the material is totally dissolved to obtain leaching liquid; and (S3) replacement: the leaching liquid is diluted and stirred; zinc powder is slowly added; in the process, the pH of the leaching liquid is kept lower than 03; and sponge indium is obtained The indium recovery method adopts oxidation under high potential to leach out In in InP, prevents generation of virulent PH3, is high in leaching rate and recovery rate, adopts concentrated hydrochloric acid and sodium chlorate to leach, and is simple in operation and low in cost
Patent•
17 May 2017
TL;DR: In this article, a sodium chlorate type acid etching liquid off-line regeneration system is described, which consists of a preparation unit, an electrolysis unit, a sodium ion reuse unit and an etching tank.
Abstract: The invention discloses a sodium chlorate type acid etching liquid off-line regeneration system which comprises a sodium chlorate preparation unit, an electrolysis unit, a sodium ion reuse unit, a temporary chloric acid storage tank, a copper extraction unit, a regeneration unit, a temporary electrolyte storage tank and an etching tank, wherein the sodium chlorate preparation unit, the electrolysis unit, the sodium ion reuse unit, the temporary chloric acid storage tank, the copper extraction unit, the regeneration unit, the temporary electrolyte storage tank and the etching tank are connected in sequence through process pipelines and conveying pumps; and a controller controls the conveying pumps and valve groups to adjust and control operation of the whole regeneration system. According to the sodium chlorate type acid etching liquid off-line regeneration system, sodium chlorate is prepared through the electrolysis unit; a copper plate is extracted from etching waste liquid directly through an electrolysis mode; meanwhile, HClO3 and Cu(ClO3)2 medicinal liquor can be regenerated, so that an efficient etching rate is guaranteed, and zero-adding and zero-discharge cyclic regeneration operation of sodium chlorate type etching liquid is realized; and by the adoption of an off-line mode, the whole regeneration system is convenient to operate and low in energy consumption and can directly and efficiently extract a flexible copper plate with high quality.
Patent•
23 Nov 2017
TL;DR: A gaseous antirust agent for black metal, comprising 15-60 parts of clay, 20-70 parts of diammonium hydrogen phosphate, 15-80 parts of ammonium bicarbonate; 20-60 part of sodium nitrate; and 1-8 parts of sodium chlorate, is described in this paper.
Abstract: A gaseous antirust agent for black metal, comprising: 15-60 parts of clay; 20-70 parts of diammonium hydrogen phosphate; 15-80 parts of ammonium bicarbonate; 20-60 parts of sodium nitrate; and 1-8 parts of sodium chlorate.