I'm interested in biosorption process for heavy metals removal. So,I have to decide which system and operating conditions can be used for this purpose.
The biosorption process depends up on many factors such as pH, Contact time, Concentration of biosorbents, and temperature. These parameters will be different for different biosorbents. Hence it will be ideal to optimize these parameters in a batch experiment.
Then to scale up the process, you can use adsorption columns.
The recovery of metals after biosorption, regeneration of biosorbents for repeated use, and improving the biosorption capacity by pretreatments are interesting areas of research.
I have done few works on the biosorption of Cd using the leaf biomass of some commonly available weeds. But didn't try the pretreatments.