A patent for an invention is the grant of a property right to the inventor, issued by the United States Patent and Trademark Office. Patents searches are conducted to determine whether a particular invention is original or has already being patented.
SciFinder indexes chemical patents from around the world (59 countries as of this month).
Patent numbers are the standard ways of identifying patent documents. Each patent number is composed of seven digits. The letters in front of each seven digit number is country code. Examples US 5997728 (USA), CA 2130816 (Canada) etc. Some other country codes are CH(Switzerlang), FR (France), JP (Japan), EP (European) and WO (International).
You could also search for a patent by using the name of the author, the title of the patent or the company name such as Winston-Salem State University. It is extremly difficult to do a keyword search for a patent.
Author search: Yusuf G Adewuyi
Title search: Fluidized catalytic cracking
Patent number search: US 5997728