Arab leaders yesterday evening opened a summit conference ostensibly designed to stop Egyptian President Anwar Sadat from concluding a separate peace with Irsael.

But with such an Egyptian-Israeli deal considered a foregone conclusion, Sadat's powerful moderate friends, led by oil-rich Saudi Arabia, appeared determined to prevent Egypt's formal isolation or condemnation by fellow Arab.

Symptomatic of the majority view was the moderate tone of the opening speech by Iraqi President Ahmed Hassan Bakr, until recently regarded as an ultra-extremist even by radical Arabs.

Another straw in the wind was the absence of radical Libyan leader Muammar Qddafi. He apparently preferred to stay away from Baghdad rather than accept the new lowest common denominator of Arab unity favored by the moderates and the host country Iraq.

Addressing only 12 of his 21 fellow heads of state of the Arab League, Bakr said. "We are not trying to isolate Egypt." He replied indirectly to tough anti-Egyptian demands that prevented Arab foreign ministers from reaching agreement over the past four days by saying, "We must not fall victims to emotional reaction and thus wrongly take a negative stand toward the people of Egypt."

Syria, the Palestine Liberation Organization and other members of the "Front for Steadfastness and Confrontation," formally favored specific demands calling for the removal of Arab League headquarters from Cairo, and an economic boycott exclusion of Egypt from Arab world affairs.

While personally blaming Sadat for accepting the Camp David accords, which he described as "stabbing where it hurts most," Bakr still clung to the outside chance that the Egyptian leader might yet change his mind.

Somewhat cynically, many observers here expect Egypt and Israel to hold off final agreement in Washington just long enough to get the summit participants, out of Baghdad and thus avoid tempting them into condemning Sadat.

Dusting off his rejected offer to provide Sadat with $5 billion a year for a decade, Bakr said, "We, who have the money, must ensure his economic needs" to enable Sadat to reject the separate peace.

Insisting no less than eight times on the need for minimum unity, the Iraqi leader hinted that it was in part because of his host's role that his present stand "differs in volume and quantity" from past positions.

A major problem for the heads of state, which has been left unsaid so far is the advisibilty of producing an alternative to the Camp David proposals in the form of a credible overall Middle East peace approach.

In keeping with the moderate line, Arab League Secretary General Mahmoud Riad condemned the Camp David agreement for failing to provide a comprehensive Middle East peace, a Palestinian state, or an Israeli withdrawal from all occupied Arab land.

That water-down criticism, although initially surprising coming from such a high Egyptian and Arab League official, is now the standard Saudi line.

Another major problem left for the summit to settle is what individual portions of $4 billion suggested earlier by Iraq should be given Syria, Jordan the PLO and Egypt. Arab oil largesse for these recipients, approved at the 1974 summit conference in Rabat, Morocco, is due to run out at the end of this year.

Indicative of the tough Saudi line throughout the four-day foregin ministers meeting was Foregin Minister Prince Saud Faisal's curt warning to radicals that any punitive act against Egypt or the United States would be considered aimed directly against the Riyadh regime.

Analysts noted that as so often in the past Syria began with a radical stance, then moderated its position to ensure not cutting itself off from future American diplomatic support, alienating Saudi funding or encouraging a preemptive Israeli military strike.

PLO leader Yasser Arafat, who missed the opening session, arrived here from Moscow later in the day.

Besides Qaddafi, other heads of state missing for apparently political reasons were from Djibouti and three pro-Egyptian states, Oman, Morocco and the Sudan.

Absent for medical were ailing King Khalid of Saudi Arabia and presidents Houari Boumediene of Algeria2711