For decades, the United States and other wealthy countries have been dependent on China to buy and process almost half of the world’s plastic waste. Now, stricter recycling standards in China mean its cheaper for some US cities to simply send recyclables to the dump rather than pay a higher fee to process them. That’s why a number of researchers and tech companies are working on robots to make US recycling more efficient. *** Correction *** at 2:19 we describe the capacity of the Mobro 4000 as 3,000 pounds. The actual capacity is 3,000 tons.