2CH4=C2H2+3H2 3C2H2=C6H6 C6H6+3H2=C6H12 C6H12+CL2=C6H11Cl+Hcl CH4+Cl2=CH3Cl+HCl CH3CL+CL2=CH2CL2+HCL CH2CL2+CL2=CHCL3+HCL CHCL3+CL2=CCL4+HCL