In order to study the effects of the volumetric flow rate in the single component adsorption of zinc and cadmium in activated bone char, the feed concentration was 1.06 meq*[L.sup.-1] for zinc solution, 4.34 meq*[L.sup.-1] for cadmium solution, and the flow rates analyzed were 4, 6, 8, 10 and 12 mL*[min..sup.-1] for both metals.
These results indicate that cadmium ions are preferentially adsorbed on the bone char. However, Figure 3 shows that the equilibrium concentration used in the trials with cadmium were higher than the trials with zinc, explaining the difference in ([q.sub.m]) between the systems.
This fact suggests that mass transfer coefficients on the bone char for zinc and cadmium in fixed bed depend on concentration, because concentration variations affect the removal rate and adsorption capacity.
This study sought to contribute to the understanding of the interactions between ions from an electrolytic solution and bone char and the main conclusions were:
These results show that the bone char preferentially adsorbs cadmium ions due to a higher affinity between [Cd.sup.2+] and the surface of bovine bone char.
Based on the absorption theory, the hydroxylapatite in bone chars
can be used to remove fluoride and metal ions from water, making it useful for the treatment of drinking supplies.
WOULD PURCHASE YOUR FAVORITE DESSERT CONTAINING SUGAR WHITENED THROUGH A BONE CHAR
FILTER, IF BONE CHAR
IS NOT IN THE SUGAR 21% Total 3% Vegans 21% All Vegetarians including vegans 20% Vegetarians not including vegans All those that eat one or more vegetarian meals per week, not including vegetarians/vegans.
In 1997, The VRG reported that Refined Sugars, Inc., maker of Jack Frost sugar, used granular carbon instead of bone char. Refined Sugars was one of the companies bought out by Domino, which uses bone char for most of its sugars.
Imperial Sugar produces a turbinado sugar that has not been processed through bone char. The Imperial Sugar Company is part owner of Wholesome Sweeteners, which produces several brands of sweeteners that are not filtered through bone char.
Sugar Corporation, uses a 'new' sugar refining process that does not involve bone char. U.S.
Hundreds of years ago, sugar refiners discovered that bone char from cattle worked well as a whitening filter, and this practice is now the industry standard.
Bone char filtering is never used in beet sugar processing.