China visa for Spanish Citizen in Moscow

Hi! I'm form Spain, and I'm going to Moscow in 15 days to begin a transsiberian trip, and i have no time to apply for the Chinese Visa, here in Barcelona, cause I'm applying for the Mongolian one just now.

It is possible to apply for it in Moscow? we already have our Russian Tourist Visa.

I need an invitation letter? Here in Spain is not necessary.

Thank you