How to use RSA Encryption using Custom Keys programatically?

Hi,

I am looking for some examples on how to use RSA Encryption using custom keys from code to encrypt config sections. My goal is to build a tool that I can use to provide multiple web applications access too, probably a class library.

I want the class library to use a single account and impersonate that account to read the RSA key container. <--  Will this work and help me avoid having to grant read access for each web application account to the RSA key container?

I was also considering using a single App.config in the class library  to hold the encrypted values. Would this be bad practice, using a single app.config instead of encrypting the web.config file sections of individual web apps.

Is there a better way? Has someone already created a library like this and can help me avoid reinventing the wheel?

Thanks!
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