Abstract: In carbonation decomposition process of alumina production with sintering process，carbonation decomposition rate according to the fine liquid of silicon content index and product quality of aluminum hydroxide is usually controlled in 90%，and 10% of the alumina residues in the spent carbonated liquor，with the evaporation mother liquor back，go round and begin again through the sintering and dissolution processes.Therefore，the alumina production cost was increased.For the better utilization of carbon residual alumina in carbonated liquor，the preparation of solid sodium aluminate with carbonated liquor was investigated. Research results showed that，solid sodium aluminate products could be prepared through thorough carbonation decomposition，recycling of solid material and sintering，namely，this method can fully recycled residual alumina from spent carbonated liquor.

Key words: aluminum oxide, carbonated liquor, carbonation decomposition, solid sodium aluminate