Potassium hydrogen phthalate plus#

In this work, kinetics of substitution accelerated cellulose hydrolysis with multiple reaction stages was investigated to lay foundation for mechanism study and molecular design of substituting compou. Dissolve the residue and 0.12 mg of sulfate ion (SO 4)in sufficient water to make 25mL, and add 0.5 mL of 1 N hydrochloric acid and 2 mL of 12% barium chloride reagent solution.Articles 88 More Articles Accelerated hydrolysis of substituted cellulose for potential biofuel production: kinetic study and modeling. Any turbidity should not exceed that in a standard prepared as follows: Treat 1 g of sodium carbonate with 2 mL of 30% hydrogen peroxide and 5 mL of hydrochloric acid, and evaporate to dryness on a hot plate (~100 ☌). Add to this solution 0.5 mL of 1 N hydrochloric acid and 2 mL of 12% barium chloride reagent solution. Dissolve the residue in 10 mL of water, filter, wash with several portions of water, and dilute the filtrate with water to 25 mL. Add 5 mL of hydrochloric acid, and evaporate to dryness on the hot plate.

Treat the residue with 20 mL of water and 2 mL of 30% hydrogen peroxide, and heat on a hot plate (~100 ☌) for 15 min. Mix 2.0 g with 1 g of sodium carbonate, add in small portions 15 mL of water, evaporate, and thoroughly ignite, taking care to protect the sample from the flame because of the presence of sulfur compounds in the natural gas.

Potassium hydrogen phthalate plus#

Calculate the number of milliequivalents of total alkali (sodium carbonate plus sodium hydroxide) required to neutralize exactly 1 g of the sample of potassium hydrogen phthalate and of the NIST SRM by the following equations: The end point of the titration is determined by the second derivative method. Titrate each solution with 0.02 N carbonate-free sodium hydroxide using a combination electrode (glass–calomel or glass–silver, silver chloride) for the measurement of E in millivolts or pH. Cool the solutions to room temperature in an ice bath, and dilute to 75–80 mL with carbon dioxide-free water.

Boil the solutions gently for 20 min to complete the removal of carbon dioxide, taking care to prevent loss of solutions by spraying. Dilute the contents of each titration flask with water to about 90 mL, swirl to dissolve the samples, stopper, and bubble carbon dioxide-free air through the solutions at a moderately fast rate during all subsequent operations. In the same manner, add to one of these flasks 5.100 ± 0.003 g of the potassium hydrogen phthalate to be assayed and to the other flask the same weight of the NIST SRM potassium hydrogen phthalate-both of which have been previously crushed (not ground) in an agate or mullite mortar to approximately 100 mesh fineness, dried at 120 ☌ for 2 h, and cooled in a desiccator for at least 2 h. Rinse the beakers, funnels, and sides of the flasks thoroughly with several small portions of water. Transfer the portions of sodium carbonate to 500 mL titration flasks by pouring them through powder funnels. Store the beaker in a desiccator until ready for use, weigh each bottle again, and determine by difference, to the nearest 0.1 mg, the weight of each portion of sodium carbonate. Open the weighing bottles momentarily to equalize the pressure, weigh each bottle and its contents to the nearest 0.1 mg, and transfer the entire contents of each bottle to a clean, dry 50 mL beaker. Dry at 285 ☌ for 3 h, stopper the bottles, and cool in a desiccator for at least 2 h. Place duplicate 1.300 ± 0.001 g portions of a uniform sample of anhydrous sodium carbonate in clean, dry weighing bottles.