removes the poison to leave the catalyst surface as it was before. The catalyst will regain its normal activity during some hours of normal operation on pure gas. However, gross poisoning leads to bulk changes which are not readily reversed: in this case the poisoning is irreversible. Poisoned catalyst can hardly be regenerated, and therefore the best method to reduce poisoning is to decrease to acceptable levels the poison content of the feed. This is generally achieved by appropriate treatments of
Chapter 2: Literature Review 2.1 Introduction In Malaysia, deep basements have been extensively constructed, especially in the last 10 years, to effectively utilise the underground space for car parks and other usage in the expensive and congested urban area (Gue & Tan, 1998). Good foundation design and construction practice means not only insulating to save energy, but also providing effective structural design as well as moisture, termite, and radon control techniques where appropriate (John, Jeffrey