[Hagrid]

This is a practice problem for the exam I have next week that I got that I can't do. Walkthrough appreciated! thank you!

Using the data in Table 1, below, calculate values of the distribution coefficient, Kd = qPb2+ / CPb2+, where qPb2+ = concentration of adsorbed Pb2+, and CPb2+ = concentration of residual dissolved Pb2+, for Pb2+ adsorption by a landfill environmental liner comprised of the clay mineral vermicullite, (Mg, Fe2+,Al)3(Al,Si)4O10(OH)2•4(H2O).  Then estimate the maximum adsorption capacity (“qmax”) of the liner material for Pb2+ by plotting Kd vs. qPb2+, and classify the type of adsorption isotherm by plotting qPb2+  vs CPb2+.
TABLE 1. Data from lead adsorption experiment on montmorillonite clay.

qPb2+            CPb2+
mmol kg-1    μmol L-1 [/b]
19                  136
28                  320
41                     717
48                 1,180
52                1,640
54               2,120
61               3,750
67                9,760


Sorry about my *explicitive* table formatting

Edit: hold on, just read the forum policy. Sorry

I am posting basically cause I can't do this one, so I don't really know what to write.  BUT: I can do the last step:

'Then estimate the maximum adsorption capacity (“qmax”) of the liner material for Pb2+ by plotting Kd vs. qPb2+, and classify the type of adsorption isotherm by plotting qPb2+  vs CPb2+.' Because I had similar question where I was shown how to do this end step, but I didn't have to do the chemical calculations at the start. Basically once I plot 'it' I will get the point where it flattens out in the graph and that is my max, and the adsorption isotherm is determined by the shape (I have in my notes to compare the shapes and determine the right one).