She can go to any of those big Chinese banks, such as Bank of China, China Construction Bank, and T/T to you. The bank will convert Chinese yuan into U.S dollar based on the daily exchange rate and only a couple of hundards Chinese yuan for T/T fee. The limitation of one individual account is $50,000 abroad remitting annually , but I just heard it has been increased up to $200,000. You don't need to pay any tax to the U.S government because it is not your abroad revenue, but your information will be reported to IRS by the American bank due to policies.
I used China Construction bank to T/T Bank of America, and the fund reached in 3 days, because Bank of America is one of the shareholders of China Construction bank and they deal with this kind of transfers more conveniently and faster than other channels.