April 22 (Reuters) - The mainstream quotation range for xylene in the South China market is 6,800-6,900 yuan/ton, down 200 yuan/ton from the previous trading day. Sinopec South China Company lowered its listed price for xylene by 200 yuan/ton to 6,900 yuan/ton. Sustained increases in crude oil prices have provided cost support, and downstream buyers showed some willingness to replenish stocks at lower prices earlier, giving the market some upward momentum. However, demand for gasoline blending remains weak, and traders are cautious, with insufficient buying interest in the market. Today, petrochemical companies lowered their ex-factory prices, and the spot market followed suit with declines.