Sequestering agents, hydrogen

Figure 10.27 Effect of sequestering agent concentration on the decomposition of hydrogen peroxide and degree of polymerisation of cotton cellulose [236]...

After examining the reaction with several hydrogen sequesting agents Morrow and McFarlan concluded that three factors play a role in determining the number of nonisolated hydroxyls which react with a given product ... 

Figure 10.4 Difference spectra of the modification reaction ofAerosil with different hydrogen sequesting agents, showing the spectral changes in the first three time intervals. Spectra were taken every 2 seconds for BCl3, thus difference spectrum 1 corresponds to the Os minus the 2 s spectrum.

Besides boron and silicon compounds, many other hydrogen sequestering agents have been used in the last decades to modify the silica surface. The reasons for such a surface modification vary from a purely fundamental study (gaining a better insight in the nature of the silica surface) to the creation of new materials, with outstanding properties. 

It is used in food products, primarily to adjust the pH of solutions. It is also used as a sequestering agent. The anhydrous material is used in effervescent tablet formulations. Sodium citrate is additionally used as a blood anticoagulant either alone or in combination with other citrates such as disodium hydrogen citrate. 

Figure 4. Infrared spectra of fumed silica A-150 after complete reaction at 22 0 C with the indicated hydrogen-sequestering agent or after H-D exchange with D2O. The integrated intensities are shown in Table I.

Sequestering agent for heavy metals these cause trouble by provoking a rapid decomposition of the peroxides through dismutation of the hydrogen peroxide formed, which deteriorates cotton and can corrode the washing machines. 

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