▎ 摘　　要

NOVELTY - Preparing sandwich-type long-term salt-resistance gel photothermal evaporator, comprises e.g. adding inorganic metal salt, nano-carbon, nano-attapulgite, and plant fiber or man-made fiber into alcohol-water mixed solution and stirring, adding 1,2-propylene oxide into the alcohol-water mixed solution, placing in mold and allowing to stand for gelation, and drying to obtain inorganic metal salt-nano carbon composite airgel, immersing one side of the inorganic metal salt-nano carbon composite airgel in a hydrophobic agent for hydrophobic treatment to obtain a hydrophobic layer of the photothermal evaporator, and adding inorganic metal salt, nano-attapulgite and plant fiber or man-made fiber into the alcohol-water mixed solution, adding 1,2-propylene oxide into the alcohol-water mixed solution, and immersing the hydrophobic layer in the mixed solution to obtain water supply layer of the photothermal evaporator. USE - The sandwich-type long-term salt-resistance gel photothermal evaporator is useful in seawater desalination, salt lake brine concentration, chemical wastewater resource utilization and other solar evaporation utilization fields. ADVANTAGE - The method: improves the mechanical strength of the gel to meet the application requirements; and has capillary action of the rich micro-nano pores of the composite airgel and the heat collection efficiency of the nano-carbon which are the core components for efficient water evaporation. The photothermal evaporator: has high evaporation rate of 1-3.5 kg/m2×h; and solves the problem of the efficiency drop of the conventional evaporator due to salting out. DETAILED DESCRIPTION - Preparing sandwich-type long-term salt-resistance gel photothermal evaporator, comprises (i) adding inorganic metal salt, nano-carbon, nano-attapulgite, and plant fiber or man-made fiber into alcohol-water mixed solution and stirring until uniform, dropwise adding 1,2-propylene oxide into the alcohol-water mixed solution and mixing well, then placing in mold and allowing to stand for gelation, and drying to obtain inorganic metal salt-nano carbon composite airgel, which is light absorbing layer of photothermal evaporator, (ii) immersing one side of the inorganic metal salt-nano carbon composite airgel in a hydrophobic agent for hydrophobic treatment to obtain a hydrophobic layer of the photothermal evaporator, and (iii) adding inorganic metal salt, nano-attapulgite and plant fiber or man-made fiber into the alcohol-water mixed solution and stirring evenly, dropwise adding 1,2-propylene oxide into the alcohol-water mixed solution, and immersing the hydrophobic layer in the mixed solution and allowing to stand to obtain water supply layer of the photothermal evaporator; where the sandwich-type long-term salt-resistance gel photothermal evaporator includes inorganic metal salt-nano carbon composite airgel as upper light absorbing layer, lower water supply layer and a middle hydrophobic layer. DESCRIPTION OF DRAWING(S) - The diagram shows schematic representation of sandwich-type long-term salt-resistance gel photothermal evaporator.