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Bicarbonate additive

Widely used additives as chlorides (NaCl, KC1) and/or bicarbonates (NaHC03, KHC03), which affect the solubility of Ca and other species, increase ionic strengths and increase the activity of the (bi-)carbonate ions. Sugar-type additives have also been used. Phosphor in the feedstock ends up less in the product when bicarbonate additives are used. [Pg.360]

Since RDDR values are unavailable for dogs (EPA 1994), ATSDR used a default uncertainty factor of 3 for extrapolating from animals to humans as it incorporates the differences in physiology between dogs and humans. A default factor of 3 was used rather than the standard factor of 10 because of similarities in renal physiology between the two species, i.e., both acidify the urine by active transport of bicarbonate. Additional uncertainty factors of 3 for use of a minimal 1 O AFT. and 10 for human intraspecies variability are used to calculate the intermediate-duration intermediate MRL. [Pg.419]

The interactions with calcium var) the organic size depending on the organic concentration. Metal complexation showed an increase in size in UF fractionation (Aster et al. (1996)). The ions present in river water were measured simultaneously with UF fractionation to ascertain how they interact with HSs of various sizes (Kiichler et al (1994)). In concentrated solutions aggregate formation is favoured, while for low concentrations intramolecular contractions result in smaller sizes (Engebretson and von Wandruszka (1994)). Huber (unpublished) reported a decrease in measured size with calcium bicarbonate addition. [Pg.27]

Giesting, D.W., Roos, M.A. and Easter, R.A. (1991) Evaluation ofthe effect of fumaric acid and sodium bicarbonate addition on performance of starter pigs fed diets of different types. Journal of Animal Science 69 2497-2503. [Pg.51]

To examine the ii ibition observed above, 15mM hydro5Qriamine (pH 7.2) was used as an artificial electron donor to PSII. A comparison of trace 2 (short formate-treatment) with trace 1 (control) in Fig. 2 shows quenching of fluorescence in heated (45 C, 3min) and hydrox-ylamine-treated Chlamvdomonas cells. Trace 3 shows restoration of fluorescence by lOmM bicarbonate addition. The same fluorescence quenching was observed in the presence of hydrojQ lamine as in its absence also in spinach leaf discs. These data suggest that the inhibition of the electron flow is located between the site of electron donation by hydroxylamine (Z or D) and Q. We call this site 1. [Pg.512]

Other manipulated variables are the acid, base or bicarbonate addition rates to control the pH or alkalinity in the bioreactor or the feed (Find et al., 2001). The pH and alkalinity control require the addition of chemicals, which raises the cost of the process. An alternative is to recycle the CO2 produced in order to increase the alkalinity, but this is not effective in the case that the bioreactor pH is lower than 6.5 (Romli et al., 1994). [Pg.287]

Dichlorobutane. Place 22-5g. of redistilled 1 4-butanediol and 3 ml. of dry pyridine in a 500 ml. three necked flask fitted with a reflux condenser, mechanical stirrer and thermometer. Immerse the flask in an ice bath. Add 116 g. (71 ml.) of redistilled thionyl chloride dropwise fix>m a dropping funnel (inserted into the top of the condenser) to the vigorously stirred mixture at such a rate that the temperature remains at 5-10°. When the addition is complete, remove the ice bath, keep the mixture overnight, and then reflux for 3 hours. Cool, add ice water cautiously and extract with ether. Wash the ethereal extract successively with 10 per cent sodium bicarbonate solution and water, dry with anhydrous magnesium sulphate and distil. Collect the 1 4-dichloro-butane at 55-5-56-5°/14 mm. the yield is 35 g. The b.p. under atmospheric pressure is 154 155°. [Pg.275]

Equip a 1-litre three-necked flask with a powerful mechanical stirrer, a separatory funnel with stem extending to the bottom of the flask, and a thermometer. Cool the flask in a mixture of ice and salt. Place a solution of 95 g. of A.R. sodium nitrite in 375 ml. of water in the flask and stir. When the temperature has fallen to 0° (or slightly below) introduce slowly from the separatory funnel a mixture of 25 ml. of water, 62 5 g. (34 ml.) of concentrated sulphuric acid and 110 g. (135 ml.) of n-amyl alcohol, which has previously been cooled to 0°. The rate of addition must be controlled so that the temperature is maintained at 1° the addition takes 45-60 minutes. AUow the mixture to stand for 1 5 hours and then filter from the precipitated sodium sulphate (1). Separate the upper yellow n-amyl nitrite layer, wash it with a solution containing 1 g. of sodium bicarbonate and 12 5 g. of sodium chloride in 50 ml. of water, and dry it with 5-7 g. of anhydrous magnesium sulphate. The resulting crude n-amyl nitrite (107 g.) is satisfactory for many purposes (2). Upon distillation, it passes over largely at 104° with negligible decomposition. The b.p. under reduced pressure is 29°/40 mm. [Pg.306]

BrCHisCHjBr + 2NaOH —> HOCHjCHisOH + 2NaBr Industrially, it is produced directly from ethylene by the addition of hypo, chlorous acid, followed by treatment of the resulting ethylene chlorohydrin with sodium bicarbonate solution ... [Pg.444]

Into a 1-litre beaker, provided with a mechanical stirrer, place 36 - 8 g. (36 ml.) of aniline, 50 g. of sodium bicarbonate and 350 ml. of water cool to 12-15° by the addition of a little crushed ice. Stir the mixture, and introduce 85 g. of powdered, resublimed iodine in portions of 5-6 g, at intervals of 2-3 minutes so that all the iodine is added during 30 minutes. Continue stirring for 20-30 minutes, by which time the colour of the free iodine in the solution has practically disappeared and the reaction is complete. Filter the crude p-iodoaniline with suction on a Buchner funnel, drain as completely as possible, and dry it in the air. Save the filtrate for the recovery of the iodine (1). Place the crude product in a 750 ml. round-bottomed flask fitted with a reflux double surface condenser add 325 ml. of light petroleum, b.p. 60-80°, and heat in a water bath maintained at 75-80°. Shake the flask frequently and after about 15 minutes, slowly decant the clear hot solution into a beaker set in a freezing mixture of ice and salt, and stir constantly. The p-iodoaniline crystallises almost immediately in almost colourless needles filter and dry the crystals in the air. Return the filtrate to the flask for use in a second extraction as before (2). The yield of p-iodoaniline, m.p. 62-63°, is 60 g. [Pg.647]

Bisulphite compounds of aldehydes and ketones. These substances are decomposed by dilute acids into the corresponding aldehydes or ketones with the liberation of sulphur dioxide. The aldehyde or ketone may be isolated by steam distillation or by extraction with ether. Owing to the highly reactive character of aldehydes, the bisulphite addition compounds are best decomposed with saturated sodium bicarbonate solution so um carbonate solution is generally employed for the bisulphite compounds of ketones. [Pg.1079]

METHOD 2 [102]-Sodium bicarbonate and dH20 are stirred in a 3-neck flask with two addition funnels attached. One funnel has... [Pg.208]

Although the process requires the addition of a phosphate donor, such as glycerol-2-phosphate, it may be a valuable tool for cleaning water contaminated with radionuchdes. An alternative mode of uranium precipitation is driven by sulfate-reducing bacteria such as Desulfovibrio desulfuricans which reduce U(VI) to insoluble U(IV). When combined with bicarbonate extraction of contaminated soil, this may provide an effective treatment for removing uranium from contaminated soil (85). [Pg.37]

Manufacture. Lithium fluoride is manufactured by the reaction of lithium carbonate or lithium hydroxide with dilute hydrofluoric acid. If the lithium carbonate is converted to the soluble bicarbonate, insolubles can be removed by filtration and a purer lithium fluoride can be made on addition of hydrofluoric acid (12). High purity material can also be made from other soluble lithium salts such as the chloride or nitrate with hydrofluoric acid or ammonium bifluoride (13). [Pg.206]

The avadabihty of CO2 and the pH ate intimately related because the preferred pH range for growth of many species, such as Chlorella is pH 6.5—7.0 and most of the CO2 is bound as bicarbonate (HCO3 ) in solution. Additional CO2 beyond that present in air (0.03%) must be provided to attain optimum growth. [Pg.464]

The pH must be kept at 7.0—7.2 for this method to be quantitative and to give a stable end poiut. This condition is easily met by addition of soHd sodium bicarbonate to neutralize the HI formed. With starch as iudicator and an appropriate standardized iodine solution, this method is appHcable to both concentrated and dilute (to ca 50 ppm) hydraziue solutious. The iodiue solutiou is best standardized usiug mouohydraziuium sulfate or sodium thiosulfate. Using an iodide-selective electrode, low levels down to the ppb range are detectable (see Electro analytical techniques) (141,142). Potassium iodate (143,144), bromate (145), and permanganate (146) have also been employed as oxidants. [Pg.287]

Control of chromium penetration, essential to permit tannage of the center of the hide, is accompHshed by pH adjustment. At a pH > 3.0 the reactivity of the hide to the chromium complex is greatiy increased. The pH is therefore raised gradually to the desired point by addition of a mild alkah, usually sodium bicarbonate. The chemistry of chrome tanning involves competing reactions that must be controlled for satisfactory results. [Pg.84]

There are occasions where the mud pH must be lowered such as after drilling fresh cement or overtreatment by one of the alkaline materials discussed. Organic acids that have been used for this purpose include acetic acid [64-19-7], citric acid [77-92-9], and oxaHc acid [144-62-7]. These materials are used infrequently. Inorganic additives used to lower pH levels include sodium bicarbonate [144-55-8] and sodium acid pyrophosphate [7758-16-9] (SAPP). Of the two, sodium bicarbonate is used the most by far. [Pg.181]

Lignosulfonate has been reported to increase foam stabihty and function as a sacrificial adsorption agent (175). Addition of sodium carbonate or sodium bicarbonate to the surfactant solution reduces surfactant adsorption by increasing the aqueous-phase pH (176). [Pg.193]

The cmde phthaUc anhydride is subjected to a thermal pretreatment or heat soak at atmospheric pressure to complete dehydration of traces of phthahc acid and to convert color bodies to higher boiling compounds that can be removed by distillation. The addition of chemicals during the heat soak promotes condensation reactions and shortens the time required for them. Use of potassium hydroxide and sodium nitrate, carbonate, bicarbonate, sulfate, or borate has been patented (30). Purification is by continuous vacuum distillation, as shown by two columns in Figure 1. The most troublesome impurity is phthahde (l(3)-isobenzofuranone), which is stmcturaHy similar to phthahc anhydride. Reactor and recovery conditions must be carefully chosen to minimize phthahde contamination (31). Phthahde [87-41-2] is also reduced by adding potassium hydroxide during the heat soak (30). [Pg.484]

Analgesic and antipyretic ibuprofen, 2-(p-isobutylphenyl)propionic acid, is converted to its monohydroxyaluminum salt by converting the acid to its sodium salt using dilute caustic, foUowed by concurrent addition of equimolar amounts of aluminum nitrate and sodium bicarbonate (84). This salt can also... [Pg.143]

Demineralizers are often used to treat raw makeup water or condensate where high purity is required, such as in large central station boHers that operate at high steam pressures. Demineralizers employ a combination of cation and anion exchange to remove additional material, including sodium and ammonium cations. VirtuaHy aH salt anions, such as bicarbonate, sulfate, and chloride, are removed and replaced by hydroxide ions in the demineralizer. [Pg.7]

Selectivity of propylene oxide from propylene has been reported as high as 97% (222). Use of a gas cathode where oxygen is the gas, reduces required voltage and eliminates the formation of hydrogen (223). Addition of carbonate and bicarbonate salts to the electrolyte enhances ceU performance and product selectivity (224). Reference 225 shows that use of alternating current results in reduced current efficiencies, especiaHy as the frequency is increased. Electrochemical epoxidation of propylene is also accompHshed by using anolyte-containing silver—pyridine complexes (226) or thallium acetate complexes (227,228). [Pg.141]

A high yield chemical pulp, eg, 52—53% bleached yield from softwoods, can be obtained, but strength properties ate inferior to those obtained from the kraft process. If a protector, eg, potassium iodide, is added, an additional 2—3% yield is obtained, as is an improvement in all strength properties. The gas penetration problem can be minimized if ftbetization is accompHshed before treatment with oxygen. Oxygen treatment of virtually all types of semichemical and mechanical pulps has been explored (55). Caustic, sodium bicarbonate, and sodium carbonate have been used as the source of base (56,57). In all cases, the replacement of the kraft by these other processes has not been justified over the alternative of pollution abatement procedures. [Pg.271]

In addition to the materials shown in Table 1, other organic materials find a minor portion of their use in mbber processing, such as waxes and fatty acids. Also, the mbber industry uses modest amounts of inorganic compounds, notably elemental sulfur, zinc oxide, magnesium oxide, and sodium bicarbonate. [Pg.219]


See other pages where Bicarbonate additive is mentioned: [Pg.50]    [Pg.378]    [Pg.26]    [Pg.304]    [Pg.228]    [Pg.188]    [Pg.3843]    [Pg.1905]    [Pg.345]    [Pg.50]    [Pg.378]    [Pg.26]    [Pg.304]    [Pg.228]    [Pg.188]    [Pg.3843]    [Pg.1905]    [Pg.345]    [Pg.273]    [Pg.324]    [Pg.617]    [Pg.772]    [Pg.901]    [Pg.937]    [Pg.222]    [Pg.157]    [Pg.202]    [Pg.382]    [Pg.47]    [Pg.493]    [Pg.182]    [Pg.155]    [Pg.275]   
See also in sourсe #XX -- [ Pg.449 ]




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