Showing papers on "Sodium sulfite published in 2013"

Optimization of Sulfide/Sulfite Pretreatment of Lignocellulosic Biomass for Lactic Acid Production

Abstract: Potential of sodium sulfide and sodium sulfite, in the presence of sodium hydroxide was investigated to pretreat the corncob (CC), bagasse (BG), water hyacinth and rice husk (RH) for maximum digestibility. Response Surface Methodology was employed for the optimization of pretreatment factors such as temperature, time and concentration of Na2S and Na2SO3, which had high coefficient of determination (R2) along with low probability value (P), indicating the reliable predictability of the model. At optimized conditions, Na2S and Na2SO3 remove up to 97% lignin, from WH and RH, along with removal of hemicellulose (up to 93%) during pretreatment providing maximum cellulose, while in BG and CC; 75.0% and 90.0% reduction in lignin and hemicellulose was observed. Saccharification efficiency of RH, WH, BG and CC after treatment with 1.0% Na2S at 130°C for 2.3–3.0 h was 79.40, 85.93, 87.70, and 88.43%, respectively. WH treated with Na2SO3 showed higher hydrolysis yield (86.34%) as compared to Na2S while other biomass substrates showed 2.0–3.0% less yield with Na2SO3. Resulting sugars were evaluated as substrate for lactic acid production, yielding 26.48, 25.36, 31.73, and 30.31 gL−1 of lactic acid with 76.0, 76.0, 86.0, and 83.0% conversion yield from CC, BG, WH, and RH hydrolyzate, respectively.

Synthesis of graphene-like materials by graphite oxide reduction

Abstract: Graphene-like materials were produced by the reduction of graphite oxide with a series of chemical reagents and high-temperature treatment. Hydrazine hydrate, hydroxylamine hydro-chloride, sodium borohydride, and sodium sulfite were used as reducing agents. The obtained materials were studied by elemental and thermal gravimetric analyses, scanning electron microscopy, X-ray diffraction, and IR and Raman spectroscopy. Depending on the used reducing agents, the graphene-like materials contained different amounts of residual oxygen.

Determination of free sulfites (SO3-2) in dried fruits processed with sulfur dioxide by ion chromatography through anion exchange column and conductivity detection.

Abstract: A simple and effective anion ion chromatography (IC) method with anion exchange column and conductivity detector has been developed to determine free sulfites (SO3-2) in dried fruits processed with sulfur dioxide. No oxidation agent, such as hydrogen peroxide, is used to convert sulfites to sulfates for IC analysis. In addition, no stabilizing agent, such as formaldehyde, fructose or EDTA, is required during the sample extraction. This method uses aqueous 0.2 N NaOH as the solvent for standard preparation and sample extraction. The sulfites, either prepared from standard sodium sulfite powder or extracted from food samples, are presumed to be unbound SO3-2 in aqueous 0.2 N NaOH (pH > 13), because the bound sulfites in the sample matrix are released at pH > 10. In this study, sulfites in the standard solutions were stable at room temperature (i.e., 15-25 degrees C) for up to 12 days. The lowest standard of the linear calibration curve is set at 1.59 microg/mL SO3-2 (equivalent to 6.36 microg/g sample with no dilution) for analysis of processed dried fruits that would contain high levels (>1000 microg/g) of sulfites. As a consequence, this method typically requires significant dilution of the sample extract. Samples are prepared with a simple procedure of sample compositing, extraction with aqueous 0.2 N NaOH, centrifugation, dilution as needed, and filtration prior to IC. The sulfites in these sample extracts are stable at room temperature for up to 20 h. Using anion IC, the sulfites are eluted under isocratic conditions with 10 mM aqueous sodium carbonate solution as the mobile phase passing through an anion exchange column. The sulfites are easily separated, with an analysis run time of 18 min, regardless of the dried fruit matrix. Recoveries from samples spiked with sodium sulfites were demonstrated to be between 81 and 105% for five different fruit matrixes (apricot, golden grape, white peach, fig, and mango). Overall, this method is simple to perform and effective for the determination of high levels of sulfites in dried fruits.

Effect of HCl on spectral properties of sulfur dioxide and its derivatives dissolved in water

Abstract: A number of studies on sulfur dioxide (SO2) in toxicology and pharmacology have been reported, however spectral properties of SO2 and its derivatives were seldom investigated. We investigated the absorption spectra of SO2, sodium sulfite (Na2SO3), sodium bisulfite (NaHSO3) and sodium metabisulfite (Na2S2O5) in aqueous solution. In the meanwhile, the effects of HCl on spectral properties of SO2 and its derivatives were also investigated. We found that gaseous SO2 in ethanol, n-butyl-alcohol and glycerol had a characteristic absorption peak at 276 nm. Na2S2O5 and NaHSO3 exhibited an absorption peak at 257 nm. Absorption of SO2 at 276 nm was strongly enhanced in the presence of HCl. NaHSO3, Na2SO3 and Na2S2O5 also exhibited absorption at 276 nm with the addition of HCl, which was enhanced with the increase of HCl concentration. Importantly, two conclusions have been reached on the basis of our results. First, we attributed the absorbing power of SO2 to SO2 molecule, rather than hydrated sulfur dioxide. Second, absorption of SO2 strongly enhanced by HCl at 276 nm was due to H+, instead of the formation of a complex SO2Cl-. Primary studies also indicated that NaHSO3 and Na2S2O5 with HCl had a similar effect as SO2 did in rat thoracic aortic rings, which prompted us believe that NaHSO3 and Na2S2O5 with HCl may be acted as a donor of SO2 in biology and other area.

Chemiluminiscence substrate liquid of alkaline phosphatase

Abstract: The invention discloses a chemiluminiscence substrate liquid capable of being applied to the field of immune detection. The chemiluminiscence substrate liquid contains 9-(4-chlorphenyl sulfobenzoyloyl methylene)-10-methyl-9, 10-dihydroacridine-disodium salt, N, N-dimethyl acridine nitrate, trihydroxymethyl amino methane, sodium sulfite, lauryl sodium sulfate and TWEEN-20. The chemiluminiscence substrate liquid disclosed by the invention is high in sensitivity, short in platform time, long in stable period of a platform and high in stability.

Aerated brick added with compound attapulgite particles

Abstract: The invention discloses an aerated brick added with compound attapulgite particles The aerated brick added with compound attapulgite particles is prepared by the following raw materials by weight: 30-40 parts of the compound attapulgite particles, 20-30 parts of fly ash, 4-6 parts of cement, 2-4 parts of shell powder, 01-03 part of sodium sulfate, 1-2 parts of hydroxypropyl methyl cellulose, 04-06 part of sodium sulfite, 07-09 part of diethylene glycol, 001-003 part of melamine, 2-4 parts of sodium chloride, 3-5 parts of calcium oxide, 03-04 part of dimethyl sodium benzenesulfonate and 008-014 part of zinc powder

Method for recycling multiple elements in acid mud generated in acid making through gold smelting

Abstract: The invention provides a method for recycling multiple elements in acid mud generated in acid making through gold smelting. The method comprises the following steps of a. pretreating the acid mud generated in acid making through gold smelting, then adding sulfuric acid, stirring the materials uniformly and carrying out roasting; b. absorbing flue gases with hot sulfuric acid and filtering the flue gases; c. adding water to a selenium-mercury mixture obtained after filtration and then adding nitric acid to completely dissolve the selenium-mercury mixture; d. using ammonia water to adjust the pH value of a solution to be 5-6, then adding an ammonium sulfide solution to adjust the pH value of the solution to be 6.5-7.5, reacting for 2-20 hours and filtering the product; e. using sulfuric acid to adjust the pH value of a selenium-containing solution to be 0.5-1.5, adding sulfuric dioxide or sodium sulfite 1.1-1.5 times the substance selenium by amount, filtering the solution and returning the waste liquor to the step b; f. leaching copper and other metal impurities from roasting slag obtained after roasting in the step a with a sulfuric acid solution, then filtering the products, extracting and recycling copper from the filtrate at normal temperature by adopting LIX 984 or adopting iron powder for replacement to obtain copper sponges; g. recycling gold and silver from filter residues with sodium cyanide.

Use of Food Additives to Control Postharvest Citrus Blue Mold Disease

Abstract: The aim of this study was to find an alternative to the chemical fungicide currently used in the control of postharvest citrus diseases. The antifungal activity of 10 salt compounds, considered as common food additives was assayed in in vitro and in vivo trials against Penicillium italicum, causal agent of citrus blue mold. Among the 10 tested salt compounds, sodium carbonate, ammonium carbonate, copper sulfate, sodium EDTA and sodium metabisulfite completely inhibited mycelial growth of Penicillium italicum at 20 mM. Colony growth of P. italicum on pH adjusted medium was evaluated. Results indicate that P. italicum can grow on both acidic and alkaline pH, with the optimum growth occurred in the range of 4.0 and 8.0. Results of the in vivo trials with tested salt compounds indicate that sodium metabisulfite (100 and 200 mM), boric acid (400 mM), sodium salicylate and sodium sulfite (200, 300 and 400 mM) completely inhibited blue mold development on citrus fruit. Boric acid (400 mM) and sodium metabisulfite (100 mM) gave the best results as they completely inhibited the fungus development without damaging fruit rind. Such healthy products therefore may represent a sustainable alternative to the use of chemical fungicides for controlling postharvest diseases of citrus fruit.

Technology for efficiently removing NOx pollutants in smoke

Abstract: The invention provides a denitration technology for efficiently removing NOx in a smoke The technology comprises the following steps: oxidizing NOx in the smoke by adopting a sodium chlorite solution as an oxidant, and processing NOx in the smoke by using a sodium sulfite solution as an absorbent to realize a removal rate of above 75% The absorbent is prepared through reacting sulfur dioxide in the smoke with sodium hydroxide, and a solution subjected to absorption reacts with calcium hydroxide to generate a sodium hydroxide solution which can be used for afresh preparing the absorbent The technology well reduces the NOx absorption cost, and is a smoke denitration technology having the advantages of high efficiency and low cost

Corrosion-inhibiting mist-suppressing promoter for steel pickling

Abstract: The invention discloses a corrosion-inhibiting mist-suppressing promoter for steel pickling, belonging to metal surface treatment chemicals. The promoter comprises, by weight, 20 to 50% of composite alkyl pyridine quaternary ammonium salt, 10 to 20% of alcohol, 5 to 10% of hexamethylene tetramine, 5 to 10% of sodium carboxymethylcellulose, 10 to 20% of an inorganic salt reducing agent, 5 to 20% of an organic metal ion chelating agent and 5 to 10% of water, wherein the inorganic salt reducing agent is one or two selected from the group consisting of sodium sulfite, sodium hydrosulfite, sodium metabisufite, sodium thiosulfate and ammonium thiosulfate, the organic metal ion chelating agent is one selected from the group consisting of aliphatic acid and a salt thereof, gluconic acid and a salt thereof, tartaric acid and a salt thereof and disodium EDTA, and the alcohol is methanol, ethanol or alkynol. The corrosion-inhibiting mist-suppressing promoter provided by the invention can substantially improve surface quality of a pickled steel plate.

Process for refining wheat-straw pulp by hydrogen peroxide enzyme method

Abstract: The invention relates to a process for refining wheat-straw pulp by a hydrogen peroxide enzyme method. A technology combining biological enzyme cold soaking catalytic decomposition with a mechanical mehtod is adopted for forming paper pulp from wheatgrass, grass is softened and dissociated at normal temperature, and fiber with physical indexes which meet the requirements of a conventional papermaking standard is formed through the mechanical mehtod. The process is as follows: soaking and softening the wheatgrass by adopting sodium hydroxide and sodium sulfite for cold soaking, then extruding a soaking solution in the wheatgrass through a screw extruder, washing, dehydrating, then enabling the wheatgrass to react with disodium edetate, sodium borohydride and hydrogen peroxidase in a thread rolling machine for fibrillation, and further forming the wheat-straw pulp required for production through a medium-concentration grinding machine and a high-concentration grinding machine. According to the process, the following raw materials in percentage by weight are used for the absolute dry wheatgrass: 16%-20% of sodium hydroxide, 0.6%-0.9% of sodium sulfite, 0.5%-2% of disodium edetate, 0.1%-0.3% of sodium borohydride and 0.5%-1.39% of hydrogen peroxidase. According to the process disclosed by the invention, biological bleaching and pulping is adopted, black liquor is not produced, a biological dissolution solution for soaking the wheatgrass can be reused for a long time, pulping water can be reused, and the production and the emission of the black liquor can be avoided during the pulping process.

Stabilized liquid preparation for injection containing pemetrexed

Abstract: The present invention relates to a stabilized liquid preparation for injection containing pemetrexed or a pharmaceutically acceptable salt thereof, and more particularly, to a liquid preparation for injection containing pemetrexed, which has improved stability as it comprises one or more types of stabilizing agent(s) selected from sodium sulfide and sodium sulfite. [Representative figure:] Fig. 1.

Method for combined removal of sulfur dioxide and nitrogen oxide in flue gas

Abstract: The invention discloses a method for combined removal of sulfur dioxide and nitrogen oxide in a flue gas. According to the method, the use level of quicklime in a desulfurization process (FGD (flue gas desulfurization)) is reduced according to the concentration of NOX to realize partial desulfurization, the remaining SO2 is used for directly reducing the NOX into nitrogen (N2), and meanwhile, the SO2 is oxidized into sulfate. The method comprises the following working flows of: efficiently absorbing the NOX and SO2 in the flue gas after the FGD process by using a solution containing metal complex, and meanwhile, converting the SO2 into sodium sulfite (Na2SO3); reacting the NOX with the metal complex to generate a nitrogenous oxide; reducing the nitrogenous oxide into N2 by using SO3 under the action of active carbon (AC) catalysis and electrochemical assistance, and oxidizing the SO3 into harmless sulfate; and regenerating a metal complex absorption solution at the same time. Along with the continuous accumulation of sodium sulfate in the regenerated absorption solution, the solution is subjected to low-temperature freezing, the sodium sulfate is separated out in the form of crystals, and the metal complex solution after recovering the sulfate is used for continuously absorbing the NOX and the SO2 to realize recycling.

Removal method of arsenic from arsenic-containing waste liquid with high acidity

Abstract: The invention provides a removal method of arsenic from an arsenic-containing waste liquid with high acidity. The method comprises the following steps of a. adding waste water after sodium sulfite desulfurization produced in a production process of a rare noble metal into the arsenic-containing waste liquid with high acidity, wherein the usage amount of the waste water after sodium sulfite desulfurization produced in the production process of the rare noble metal is 5-20 times that a theoretical usage amount of the reaction of sodium thiosulfate and arsenic in the arsenic-containing waste liquid with high acidity, reacting for 1 h-2 h at a room temperature, settling for 5 h-24 h, and filtering to obtain a leaching liquid after dearsenification for use; and b. sending the leaching liquid after dearsenification to a white ash factory for recovering zinc and nickel. In the removal method of arsenic from the arsenic-containing waste liquid with high acidity, the arsenic in the arsenic-containing waste liquid with high acidity is precipitated in an arsenic trisulfide manner by using the arsenic-containing waste liquid with high acidity produced by silver and selenium metal hydrometallurgy and adding the waste liquid after sodium sulfite desulfurization produced in the production process of the rare noble metal. The removal method has the characteristics of simple process flow, low production cost and high metal recovery rate, is based on waste control by waste, and is circularly economic.

Rust-proof cutting fluid and preparation method thereof

Abstract: The invention discloses a rust-proof cutting fluid and a preparation method thereof. The rust-proof cutting fluid comprises the following components in parts by weight: 70-90 parts of machinery oil, 15-25 parts of sulfonated oil, 10-18 parts of barium mahogany sulfonate, 10-15 parts of zinc naphthenate, 5-10 parts of boric acid, 3-8 parts of sodium citrate, 1-5 parts of sodium sulfite, and 1-5 parts of sodium dodecyl benzene sulfonate. The preparation method comprises the following steps: mixing and heating the machinery oil and the sulfonated oil to 70-90 DEG C; adding barium mahogany sulfonate, zinc naphthenate, boric acid, sodium citrate, sodium sulfite, and sodium doodecyl benzene sulfonate under the stirring state; continuously stirring until each component is dissolved; cooling to room temperature under the stirring state. Conducting tests of rust-proof performance and corrosion-proof performance on the rust-proof cutting fluid provided by the invention, the tests show that the rust-proof cutting fluid provided by the invention has well rust-proof and corrosion-proof performance.

Method and device removing nitrates from water body by single-stage autotrophic denitrification

Abstract: The invention relates to a method and device removing nitrates from a water body by single-stage autotrophic denitrification. In a biological filter, haydite is used as a filtering medium for attached growth of denitrifying microorganisms. A (sodium thiosulfate, sodium sulfite and sodium sulfide) solution is added in influent water of the biological filter to supplement electron donors required by denitrification, and purified water flows into the lake surface water body. By using single-stage autotrophic denitrification, the invention can quickly and efficiently remove nitrates in the water body, thereby enhancing the quality of the treated water and lowering the probability of eutrophication in the receiving lake water body.

Accessory ingredient capable of removing and avoiding generating hexavalent chromium in leather and preparation method of accessory ingredient

Abstract: The invention relates to an accessory ingredient capable of removing and avoiding generating hexavalent chromium in leather and a preparation method of the accessory ingredient, belonging to the technical field of chemical product manufacture. The accessory ingredient is mainly and technologically characterized by being prepared from raw materials including a reducing agent, an antioxidant, a dispersing agent, a masking agent and a pH value regulator. The reducing agent mainly comprises the following components: sodium sulfite, sodium hydrogen sulfite, sodium hyposulfate, sodium pyrosulfite and glucose; the antioxidant comprises the following components: sulfonated tannin extract, sulfited tannin extract, tea polyphenol, gallic acid, ellagic acid, vitamin C and vitamin E; the dispersing agent comprises the following components: an auxiliary naphthalene sulfonic acid synthetic tanning agent and an auxiliary phenolsulfonic acid synthetic tanning agent; the masking agent mainly comprises the following components: sodium formate, sodium acetate and sodium citrate; and the pH value regulator comprises the following components: citric acid and oxalic acid. The accessory ingredient is prepared through grinding, crushing and uniformly mixing. The accessory ingredient is few in raw material component, simpler in preparation method, free of pollution and capable of thoroughly removing and avoiding generating hexavalent chromium in leather.

Method for producing anhydrous Na2SO3 by using alkali-containing waste mother liquor

Abstract: The invention provides a method for producing anhydrous Na2SO3 by using waste mother liquor generated in the production process of soda ash dense. The method is characterized by comprising the following steps of: performing primary treatment on alkali-containing waste mother liquor; generating sulfur dioxide and washing with water; absorbing sulfur dioxide by the alkali-containing waste mother liquor which is subjected to the primary treatment; adding alkali to adjust pH value to be 8 to 14 at high temperature; standing, filter-pressing and decolorizing, and removing residues; performing vacuum concentration and evaporation on a saturated sodium sulfite solution from which the residues are removed; and performing centrifugal dewatering on sodium sulfite crystal substances and drying; and detecting the dried anhydrous sodium sulfite, metering, packaging and putting in storage. The alkali-containing waste mother liquor is used as a raw material, and the waste mother liquor absorbs sulfur dioxide so as to prepare the anhydrous sodium sulfite; therefore, the alkali-containing waste mother liquor can be purified completely; the whole process is simple, low in investment, low in energy consumption, and easy to popularize and apply, and has obvious social and economic benefits; and wastes and secondary pollution can be avoided.

Reductive calcining process of ferrous sulfate as byproduct of titanium dioxide

Abstract: The invention relates to a reductive calcining process of ferrous sulfate as a byproduct of titanium dioxide. The reductive calcining process comprises the following steps of: adding reductive substances, namely coke powder, sulphur and pyrite concentrate according to a certain proportion in a process of calcining ferrous sulfate to obtain solid substances, namely iron oxide red, wherein sulfur dioxide as a main component in waste gases can be used for producing concentrated sulfuric acid and anhydrous sodium sulfite after being purified, converted and absorbed, so that sulphur and iron resources in ferrous sulfate can be comprehensively recovered; and meanwhile the pollution to environment caused by long-term stockpiling of the ferrous sulfate as the byproduct in the titanium dioxide industry is eliminated, the ferrous sulfate residues can be recycled, valuable resources, such as sulphur and iron can be comprehensively recycled, the clean production requirement is achieved and the difficulties in the titanium dioxide industry are solved.

Device for preparing sodium metabisulfite and anhydrous sodium sulfite

Abstract: The utility model provides a device for preparing sodium metabisulfite and anhydrous sodium sulfite. The device comprises a sodium metabisulfite preparation system and an anhydrous sodium sulfite preparation system which are simultaneously connected with a sulfur dioxide gas total pipeline. A three-stage series connection countercurrent absorption structure is adopted by the sodium metabisulfite preparation system, and a secondary spray absorption structure is adopted by the anhydrous sodium sulfite preparation system. According to the device, sulfur dioxide gas generated by calcinations of sulphide ores is utilized to produce the sodium metabisulfite and the anhydrous sodium sulfite, manufacturing cost of the sodium metabisulfite and the anhydrous sodium sulfite is reduced, the utilization rate of pyritic resources is improved, the structure is reasonable, and energy conservation and environment protection are achieved.

Desulfurization method in noble metal enriching process

Abstract: The invention relates to a desulfurization method in a noble metal enriching process and relates to a desulfurization method for carrying out control potential chlorination leaching to separate out base metal elements to obtain noble metal control-potential chlorinated slag during metal sulfide ore smelting The desulfurization method is characterized by comprising the following steps of firstly slurrying control-potential chlorinated slag, adding sodium sulfite to react, filtering and washing after the reaction to obtain the desulfurized filter residue According to the desulfurization method disclosed by the invention, the noble metal enriching desulfurization is realized by utilizing the fact that the sodium sulfite and the sulfur react to generate sodium thiosulfate which is easily solved in water The sulfur in the noble metal control-potential chlorinated slag mostly exists in a form of elementary substance, sodium sulfite is added to the noble metal control-potential chlorinated slag to react so that the most of elementary sulfur in the control-potential chlorinated slag can be removed, the desulfurization rate to the control-potential chlorinated slag is more than 90%, the content of the noble metal in the generated desulfurization liquid is smaller than 0001g/L, and the noble metal loss during the desulfurization is small; and the desulfurization method has the advantages of short process flow, simpleness in operation, low production cost and small environment pollution

Carbomer gel and preparation method thereof

Abstract: The invention discloses carbomer gel and a preparation method thereof, relates to a medicament for treating gynecopathy and the preparation method thereof and specifically relates to the carbomer gel and the preparation method thereof. The invention provides the carbomer gel with good efficacy and convenience in preparation and the preparation method thereof. The carbomer gel comprises the following components in percentage by weight (accounted by 100%): 3%-8% of carbomer, 3%-5% of triethanolamine, ethylenediamine or sodium hydroxide, 20%-30% of glycerol or propylene glycol, 0.5%-1% of benzyl alcohol, benzoic acid or sodium benzoate, 0.01-0.03% of ethylenediaminetetraacetic acid disodium or sodium sulfite and the balance of water.