They need shale not to clean up their air (in a sense they do but it’s not the rationale that drives them) and also not to lower their energy bill. They need it for more independence for the rest of the world. China can be very easily blockaded by cutting off its seaports from the world. The US Navy could do that if it wanted. That would give China two immediate problems – food and energy. Shale would help to solve the second one. They will go on, no matter the cost.
China is looking to attract investments in shale gas developments by easing restrictions on foreign entities and subsidizing costs in a bid to boost its natural gas production while its demand continues to grow