The former engineer, who dropped out of the billionaire ranks during the financial crisis as his chemicals company, Ineos, struggled to handle its heavy debts, makes comeback. World's third largest chemicals company with $39 billion in sales, business got lift recently after Petrochina agreed to pay $1 billion for 50% in its European refinery operations earlier this year. Ineos had largely grown through series of acquisitions. The biggest: the $8.7 billion deal to buy BP Group's Innovene business in 2005. Headquarters shifted to Switzerland from U.K. apparently to save taxes. Mr Ratcliffe, who studied chemical engineering and worked later in venture capital, only started as an entrepreneur in 1992, aged 40, and founded Ineos just 20 years ago. It expanded quickly by buying unfashionable petrochemical assets cast off by big oil and chemicals groups. By slashing fixed costs, he soon had most of them generating lots of cash, allowing him to refinance loans. His trusted equity partners Andy Currie and John Reece each own almost one-fifth of Ineos. In 2018 his worth is about $14.5bn, according to the Bloomberg Billionaires Index, based on his 60 per cent or so equity interest in Ineos and a couple of mega-yachts. That’s maybe a conservative calculation. Named Britain’s richest person by the Sunday Times in May 2018, knighted by the British Queen in June 2018 , he’s now poised to quit the UK to live in Monaco, according to the Telegraph - sparking a fair bit of criticism given his support for Brexit. In 2010, he uprooted key staff and decamped to a village near Geneva when the Labour prime minister Gordon Brown wouldn’t let Ineos defer a big sales-tax bill. Mr Ratcliffe returned to the UK in 2016, but is now poised to disappear to Monaco, which also has a pretty favourable tax system.