Table 2 Catalytic activity and selectivity.

Catalysts	Esterification*		Friedel–Crafts alkylation ^†			CHP cleavage ^‡
	TOF (h⁻¹)^§	Conv. (%)	TOF (h⁻¹)^§	Conv. (%)	Sel. (%) ^\|\|	TOF (h⁻¹)^§	Conv. (%)	Sel. (%) ^¶
H₂SO₄	31.9	71.7	—	4.9	50.1	—	—	—
Amberlyst-15	2.4	40.2	9.3	44.0	63.6	189.4	33.3	68.6
Nafion NR50	—	—	14.7	69.1	89.2	—	—	—
PS-SO₃H HNs	6.5	25.9	14.8	69.2	60.5	62.6	9.8	69.4
PS-SO₃H@mesosilicas HNs^#	11	75.7	20.4	99.6	67.5	627.4	98.1	99.0
PS-SO₃H@mesosilicas DSNs	28.6	89.7	27.9	99.1	72.7	611.5	99.5	99.8
DMF-treated PS-SO₃H@mesosilicas DSNs	12.3	65.1	13.6	6.8	33.1	48.9	7.4	61.4

The catalytic performance of different types of acid catalysts in esterification, Friedel–Crafts alkylation and CHP cleavage reactions (see Fig. 6).
^*The esterification reaction was performed at 80 °C for 6 h under the conditions of 0.04 mmol of acid sites, 2 mmol of lauric acid and 10 mmol ethanol. The catalytic activities in esterification reaction were evaluated by lauric acid conversion.
^†The Friedel–Crafts alkylation was performed at 80 °C for 7 h under the conditions of 0.04 mmol of acid sites, 2.3 mmol of benzyl alcohol and 10 ml toluene. The catalytic activities in Friedel–Crafts alkylation were evaluated by benzyl alcohol conversion.
^‡The CHP cleavage reaction was performed at 50 °C for 1 h under the conditions of 8.7 × 10⁻³ mmol of acid sites and 5.2 mmol of CHP. The catalytic activities in CHP cleavage reaction were evaluated by CHP conversion.
^§For the calculation of TOFs, H⁺ measured by acid–base titration method were used as active sites. The TOF was defined as mmol substrate converted per acid site per hour with conversion less than 30%.
^||The selectivity to methyl diphenylmethanes.
^¶The selectivity to phenol.
^#The sample was obtained with sulphonation time of 3 h.

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