The United States has offered to destroy Syrian chemicals on an US ship.
The global chemical weapons watchdog said it is looking for a suitable Mediterranean port where processing can be carried out.
The Organisation for the Prohibition of Chemical Weapons(OPCW) has been under pressure to find an alternative plan for the destruction of Syria's poison gas arsenal after Albania backed out of hosting the work.
The OPCW said 35 firms had expressed an interest in bidding for commercial contracts by yesterday's deadline.
The contract is for the treatment of about 800 tonnes of bulk industrial chemicals that are safe to destroy in commercial incinerators.
But another 500 tonnes of chemicals, including nerve agents, are seen as too dangerous to import into a country or process commercially, and will be treated offshore on an US ship.
The OPCW said the operation would be carried out on an US vessel at sea using hydrolysis, adding a naval vessel was undergoing modifications to support the operations.
The Hague-based organisation, which won the Nobel Peace prize last month, has been given the task of overseeing destruction of Syria's chemical weapons stocks under an agreement which averted US missile strikes.
It followed a sarin gas attack on the outskirts of Damascus in August which killed hundreds of people.
Sigrid Kaag, head of the joint UN-OPCW Syria team, said today the mission faced a challenge to get the most lethal chemical agents out of Syria by the end of the year target, in the midst of a civil war which has killed 100,000 people.
She said the chemicals, located at various sites across Syria, would be packed, sealed and transported to the Mediterranean port of Latakia.