China's finance ministry announced on Friday that it will reduce or eliminate export tax rebates for a variety of commodities and products, starting December 1. 

The export tax rebate rate for certain refined oil products, photovoltaics, batteries, and specific non-metallic mineral products will decrease from 13% to 9%. 

Additionally, the rebate will be completely removed for aluminum and copper products, as well as for chemically modified oils and fats derived from animals, plants, or microbes. 

This announcement led to a surge in aluminum prices on the London Metal Exchange, as traders speculated that it could limit the significant outflow of Chinese aluminum. 

Furthermore, the news also caused a notable increase in U.S. soyoil prices, as it seemed that the changes would affect Chinese exports of used cooking oil. These exports have been competing with domestically produced feedstocks like soyoil in the U.S. and Europe. 

Typically, China's used cooking oil exports fall under the category of chemically modified oils and fats, which will no longer receive export rebates.