China Petroleum & Chemical (SHA:600028, HKG:0386), or Sinopec, reported a double-digit jump in net profit in the first half of the year, as the growth in its refining margin offset a sharp downturn in fuel demand.

Attributable net profit jumped 19% to 25.6 billion yuan, or 0.212 yuan per share, according to a Hong Kong bourse filing late Friday.

Revenue rose modestly by 2% to 1.437 trillion yuan. Sinopec attributed the soft rise in revenue to weak demand for domestic refined oil products and chemicals amid high oil prices brought about by geopolitical conflicts.

Sinopec's refining segment became the company's second-strongest profit engine during the first half after booking a 381.5% year-over-year jump in operating profit to 17.02 billion yuan, surpassing the company's marketing and distribution segment, which previously was the second-largest.

The company's refining margin was 453 yuan per tonne in the first half, up 44% year over year. Sinopec attributed the growth to significant improvements in the margins of products like kerosene, naphtha and refining by-products. These offset the impact of higher purchase premiums and freight costs of imported crude oil.

Demand for natural gas, however, slowed in the first half due to high oil prices and as customers turned to new energy products, Sinopec said. Refined oil products consumption slipped 8.6% year over year, with gasoline consumption falling 7.9% and diesel purchases falling 11.5%.

For the second half, Sinopec expects demand for natural gas to rise. In contrast, it projects a drop in demand for chemical products and refined oil products amid the transition into alternative energy.

"Given the impacts of geopolitics and changes in the global supply, demand and inventory, there will be greater uncertainties in international crude oil prices," Sinopec said.

Sinopec declared an interim dividend of 0.105 yuan per share payable in cash on or before Oct. 14 to shareholders on record as of Sept. 29.