Praxair Inc. is in preliminary talks to merge with Linde AG of Germany, in a deal that would create the world's biggest maker of industrial gases, The Wall Street Journal reported. The two have combined revenues of over $30 billion but would likely be forced to sell off some operations to appease antitrust regulators, given the existing degree of concentration in the sector. The talks are a strategic response to the recent merger between France's Air Liquide and Airgas Inc. Shares in the two companies rose by between 4%-5% in response to the report, on the hope that the combined entity would have more pricing power and a more efficient cost base. Consultants P&S say the global market for industrial gases should grow by an average of 6% a year through 2022, driven by demand from the refining sector in emerging markets, as well as the healthcare and food packaging sectors. WSJ, subscription required