Supplementary data

Feedwater pH affects phosphorus transformation during hydrothermal

carbonization of sewage sludge

Tao Wanga,b, Yunbo Zhaia,b,* , Yun Zhuc,d, Chuan Penga,b, Tengfei Wanga,b, Bibo

Xua,b,Caiting Lia,b, Guangming Zenga,b

aCollege of Environmental Science and Engineering, Hunan University, Changsha

410082, P. R. China

bKey Laboratory of Environmental Biology and Pollution Control (Hunan

University), Ministry of Education, Changsha 410082, P. R. China

cShenzhenInstitutes of Hunan University, Shenzhen518000, P. R. China

dOffice of Scientific R& D, Hunan University, Changsha 410082, P. R. China

Supplementary Figures. S1-S2.

Fig.S1 SEM images and energy spectrum of (a) dried SS and (b) resulting hydrochar

of 260-7.

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09-0345 Calcium Phosphate 45-0339 Sodium Calcium Phosphate⑤ ⑥

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(d)

Fig.S2 XRD patterns of (a) sewage sludge and resulting hydrochars after HTC with

different feedwater pH (3, 5, 7, 9 and 11) at (b) 200C, (c) 230C and (d) 260C.